You do not state whether this retreating snow matches the models, but I suspect not. Moreover, you seem to see the main danger of a melting snowpack as the lack of river water, but surely that will remain the same provided that the annual precipitation does not change. All that needs to be done is to build additional resevoirs to contain the same amount of water as that which was produced by the annual snow melt.
What you do not seem to be considering is that when the snow line rises the albedo will change, and since this ice retreat is global then the global albedo will be reduced leading to an increase in global mean temperature. This is what is causing global warming, and not the change in the radiating temperature of the tropopause, which satellites measurements have failed to find.
Most of the increased absorption and consequent warming of the air due to the increase in CO2 is happening close to the surface of the earth. Think of Beer’s Law. This is what causes the snow to melt. Lindzen is correct in that CO2 has little direct effect of global temperatures, but its indirect effect can cause and end ice ages.
[Most of the increased absorption and consequent warming of the air due to the increase in CO2 is happening close to the surface of the earth. Think of Beer's Law. This is what causes the snow to melt. Lindzen is correct in that CO2 has little direct effect of global temperatures, but its indirect effect can cause and end ice ages.
[Response: Reservoirs! Why didn't I think of that. Let's see, the total land area we are talking about is, umm,,, wait a minute, how many $billions? Wait, I've got another idea! Let' all just limit bathing to Tuesdays, and car washing to the 4th Tuesday of each month. What? That'll damage the economy. Well then lets ship in snow from Switzerland? Oh, they don't have any this year? Umm...
Look, I'm sorry for the sarcasm, but your explanation of global warming is ridiculous, which you can easily prove to yourself with the simplest energy balance model. I have zero doubt that Lindzen would agree with me. And your suggested solution to declining snowpack really is quite laughable. --eric ]
“Moreover, you seem to see the main danger of a melting snowpack as the lack of river water, but surely that will remain the same provided that the annual precipitation does not change. All that needs to be done is to build additional resevoirs to contain the same amount of water as that which was produced by the annual snow melt.”
It is exactly this don’t worry be happy there is no problem we can’t fix with technology, attitude that makes me really worry about those that advocate geo engineered solutions to problems that supposedly don’t even exist. “All that needs to be done…” I’m afraid that the mediators here might not allow my posting to be seen if I actually said what *I* think needs to be done and used the words I’d like to use, argh @#%&!!!!
Comment by Fernando Magyar — 20 Mar 2007 @ 5:49 AM
What’s all the hoo-ha? At AAAS Convention in February ’05 Tim Barnett, on the basis of his paper presenting his models,–which batted .950–predicted dry summers in twenty years for all the major highlands and mountain chains across the planet. Later,–I think the summer of ’05 –he said the rivers of the western U.S. wouldn’t be at risk because of the reservoirs, just as Alastair has it in Comment (1). As I understand it not one of the reservoirs has recovered much from the growing drought across the west. I know the Oglalla aquifer ain’t. What does puzzle me about my fellow members of “man wising-up”(homo sapiens) is their understanding of compound interest. When they invest in alternative heating supplies to transport heat out of a room to the outside of a house (air “conditioning”) they don’t consider the processes and their consequences. With Business As Usual for at least another five to ten years, here is a real good verifiable prediction: Despite the panic among Swiss Re actuaries, BUA insures that we seven billions will be halved by 2037. And I really, really, REELY hope I live to 105 to find my prediction falsified. Seeing as how we’re all of us embarked on the greatest uncontrolled experiment since we dropped from the tree, that”s the best I could come up with that’s in screaming distance of scienterrific method.
Comment by Juola (Joe) A. Haga — 20 Mar 2007 @ 5:53 AM
Please forgive my very simple questions, I’m just trying to get this straight in my mind.
If this change in global albedo is what is causing global warming, how did the process get started? I understand that the ongoing process feeds itself but if the result is the cause, surely the result cannot start the cause in the first place?
Your logical reasoning is circular and, well, simply wrong. You said that the diminishing snowpack is due to global warming, and that global warming is due to diminishing snowpack (due to reduced albedo). What do you believe started this cycle? And, if your hypothesis were true, what would keep the melting/warming from continuing until the very last flake of snow is gone from every mountain?
I would be interested to learn what the causes for this change are in atmospheric circulation that can be modeled. Certainly there is going to be more water circulating to land in a warmer atmosphere, but apparently less as snow in the Cascade region. Discussions that I have read for the eastern United States mention not necessarily less total snowfall but a shorter season so that early rains cause the snow to melt.
OK, while we’re at it, I’ll jump on the “Pick on Alastair bandwagon, too. Think for a moment about the differences in runoff for snowpack and rain. Snowpack usually melts gradually over a period of month, whereas rainfall tends to saturate the ground and then run off all at once. Not only is rainfall more likely to cause erosion, followed by dry riverbeds, it is more likely to run off without recharging groundwater.
When one seeks to base an argument on ceteris paribus (all things being equal), it’s a good idea to think it through and make sure the ceteris are in fact paribus.
[Response: I don't usually resort to sarcasm in my original response, above, but Alastair McDonald's comment must surely rank as one of the most impressive displays of know-it-all-ness I've seen yet on RealClimate. He not only knows the cause, but he knows the solution to all our global warming concerns. Still, let's make this the last "Pick on Alastair" comment. The thread is already hopelessly off topic already. -eric]
Rain run-off is very different from snow run-off. In my NW community, a heavy rain will produce a rapidly flowing turbulent creek or river, often too dirty for the filtration systems and often it requires water rationing. Snow melts at a more consistent rate and keeps the water running clean. Trying to replicate the snow melt run-off for all the rivers and creeks in the NW area currently supplying water to various communities would be a massive project. We’re not talking about a few big reservoirs located in easily accessible areas, but 100′s (often located in very difficult to access areas).
To follow up on #9 – higher snow levels presumably mean more rain events for areas formerly covered in snow throughout the winter, resulting in saturated ground. Add to that an earlier melt of the snowpack that remains, and I believe that leads to an increases probability for floods. This is a concern where I live in SW Idaho (which, while not part of the Cascades, obviously, is still considered the Pac NW if you use the Egan definition of “anywhere a salmon swims” (or swam as the case may be). I am not sure about the dam issue – could dam operators adjust their operations to capture the earlier runoff? I suppose not, if that water is falling as rain and saturating the ground and not running off, as snowpack tends to do. Any clarification on this point would be appreciated…
[Response: Yes, all of this is correct. Obviously one could in principle try to capture more of the early season runoff, but existing reservoirs tend to get overfilled in spring around here. So we'd have to increase the size of existing reservoirs. -- eric]
I wasn’t necessarily talking about new reservoirs – I agree that would be silly, though our Governor thinks we should be building more of them to keep more of our water “in state.” What I hear out this way is that we could simply adjust the operations of existing dams to catch the earlier runoff, but that point is moot if the runoff does not happen or comes all at once. My point was there are no simple solutions…
[Response:Matt, my apologies; I edited my response to your last comment and we crossed in cyberspace. In any case, I agree with you.--eric]
What I am saying is that man made CO2 is causing the snow to melt and that is causing global warming. In other words, global warming is an indirect consequence of anthropogenic greenhouse gases. They are not the direct cause, in the way they are modeled by scientists. The models are wrong, and the effects of the increase carbon dioxide over the last century will be much more severe than is currently imagined/modelled.
Of course the full story is much more complicated than that. But keeping it simple, the models are based on the idea that when the surface temperature increases, then more infrared radiation is emitted to space, but that is not how the global temperature is regulated. When the surface temperature rises, eventually more clouds form that block solar radiation. This has been the case ever since the time of the faint young sun. In other words the surface temperture has been held at a level suitable for life for over three billion years by changes to the incoming solar radiation, not by changes to the outgoing infrared radiation.
Hi Eric, The decreasing trend in snowpack is on the order of 15-30% from 1940/50 to 2004. Are there estimates of snowpack *variability* in addition to the trend, for the Cascades or parts of the Cascades? For example, I would think the most worrisome time periods for water management would be during extreme warm vs cold phases of the Pacific Decadal Oscillation, especially when reinforced by El Nino/La Nina years. Can you elaborate on how much snowpack variability you see, on top of the observed trends? Thanks — Karen
[Response: These are excellent questions. I refrained from addressing them because I felt it was important to first clarify that there is an observed trend. The question of variability vs. trend is a bit more complex, and the question of attribution (e.g. "global warming" vs. "natural variability") is not trivial. In particular see Mote, 2006. The Climate Impacts group has a good discussion of this on their website.--eric]
My first point is that we don’t have to build resevoirs to hold all the ice that is covering the mountains. It does not all melt each year. We only need enough storage during the winter to provide a supply during the summer, to augment that which is not provided by the summer rain. Of course there is a problem finding space for all those resevoirs, but when the glaciers retreat there will be a lot of unowned empty U-shaped valleys which should do very nicely :-)
I agree that I can expect little support from Lindzen, since he believes that increased CO2 is not a danger, and I am arguing the complete opposite. But he is saying that the models should not be trusted, with which I am in agreement. Moreover, in my reply to Philip #13, I pointed out that it is clouds which keep the planet cool, and that idea is not too far off Lindzen’s Iris.
Alastair, this makes zero sense. Presence or absence of CO2 does not affect the melting point of ice. And clouds form when 1)the relative humidity reaches 100% and 2)there are sufficient nucleation sites. None of these has anything to do with CO2, or indeed with surface temperature. Dry air will not saturate no matter how much you chill it.
Maybe for teh sake of clarity, you need to go into a little more detail so that we can judge whether you have the foggiest idea of what you are talking about.
On dams: Yes, theoretically, we could build more artificial reservoirs to offset the “snowpack reservoir” that is declining but you have to realize that pretty much all of the potential sites for dams in the west are taken up already. Also, it is nearly impossible (politically) to build a dam right now because of the enormous constituency in the NW to protect anadromous salmonids (fish that need to migrate up rivers from the ocean as part of their life cycle but have a hard time jumping over large dams). There are many examples, throughout the west (and the rest of the country) of dams being removed for fish passage.
Secondly, people should realize that this snowpack decline is not just isolated to the Pacific NW. The “snowpack reservoir” is absolutely essential to nearly all of western North America. For example, California’s economy would be enormously affected by even a modest decline in snowpack. I recommend the work by Dettinger, Cayan, and Stewart at Scripps who have shown a clear trend toward earlier streamflow timing in snowmelt-dominated watersheds across western North America (J. of Climate, 18(8): 1136-1155).
Finally, I have a quick question that I’ve thought a little bit about. As far as the network of snow sensors across the Cascade Range, what does their topographic distribution look like? Are the majority in fairly high elevation locations or are there are a fair amount within the snow-line transition zone? I ask because I would think that the most dramatic declines in snowpack would occur closer to that snow-line transition. Any thoughts would be great. Thanks.
One item that you didn’t mention in your summary of the UW dispute is that (at least according to the Seattle Times article) Phil Mote apparently tried to squelch debate by insisting on reviewing all e-mails issued by Albright on the snowpack issue. When Albright refused, Mote banned him from associating with the state climatologist’s office. Given that RealClimate has justifiably criticized the Bush administration for similar tactics in trying to suppress debate on climate issues in Federal agencies, I’m surprised that this didn’t merit some attention here.
Regardless of where you come down on the snowpack issue, this kind of heavy handed suppression of opposing views certainly plays into the hands of some critics of the climate science community.
[Response: Some of my RealClimate colleagues felt I should comment on this too, but I declined to comment on this because I am at UW and felt that it was not appropriate to insert myself into a personnel dispute that should be handled between the individual parties, or if necessary by the directors/chairs of the respective departments. It might be worth pointing out that Phil Mote is not in a position to threaten anyone with a loss of income. The State Climatologist's office is purely titular.--eric]
Comment by Richard Ordway — 20 Mar 2007 @ 11:54 AM
Thanks for the link, Eric. Just to clarify: I wasn’t questioning the presence of a trend, but was considering the increased vulnerability of a watershed when additional, extreme variability is imposed on the trend. But I’ll check out the resources you’ve mentioned. Cheers.
Reducing Albedo? Do you mean the reduction of the Earth’s ability to handle incomming energy from the sun? Sort of like using ice cubes to cool off a drink where the heat circulates within the drink until the ice is gone and we have a drink of equalized yet increasing temperature? In the case of the Earth, the ice cubes would be located at the poles and the drink would be the oceans and atmosphere. One more “quick” question, is the increase of CO2 homogeneous or does it hang about in certain areas on the face of the Earth or is this largely unknown.
Are there any assessments of the snowpack for the first half of the century? It seems rather ‘convenient’ to pick as your starting date for the assessment a point which coincides with the beginning of the mid-century cooling period associated with the 50′s-70′s. Wouldn’t a more accurate assesment be to compare today’s snowpack to that of the 20′s and 30′s during the peak of the early century warming?
In central California the snow pack is already melting and winter is still here. Weather reporters no longer give the cheery “what a great sunny winter”, they now show far more frowns and concerns when reporting warm winter trends.
Re #18 comment: [But in any case the snowpack loss we are talking about in the Pacific Northwest is trivial from a snow-albedo feedback point of view (except very very locally of course).]
If we’re just considering the PNW snowpack, of course, but it seems reasonable to suppose that the same reasoning would apply to all mountain ranges, and indeed, to any place with snow. So I did a bit of looking, and it seems the Sierra Nevada snowpack is melting earlier:
Based upon empirical knowledge the alleged declining snow pack is is not abnormal. We skiers know.
For example, photos taken during construction of the Timberline Lodge at Mt Hood show that the permanent snowfield above 7000′ and the glacier near the peak on the south facing slopes were missing. This year the snow pack is sufficient to permit summer skiers to ski down to the Lodge at 6000′ in August. The permanent snow field and glacier are alive and well. Natural variation of the snow pack in the Cascade Range is significant.
The Columbia River system starts in the Columbia Ice Field in Alberta. Are there any studies showing that critical ice field is shrinking? Is there any peer reviewed research indicating that precipitation will decrease in the Pacific Northwest due to increased anthropogenic gas emissions?
The form of precipitation, whether rain or snow, only determines the time of year that river flows increase from runoff. Intuition and historical records indicate that precipitation will remain constant (or perhaps increase) during warmer periods.
Thank you for your response, but I think you took my questions too seriously. I was somewhat faceously trying to point out the logical fallacy in Alistair’s first post. Other commenters did a better job of that than I did.
I have already read the links you posted and have been a committed believer in the evidence for AGW for several years. I just worry about the vast amounts of debate going on and the microscopic amount of real progress. Hopefully that will change.
Much of the period ’45-’90 is somewhat influenced by “global dimming” caused by late-industrial era pollutants, which have now largely been checked. The most recent rapid and catastrophic warming records perhaps foreshadow an inflection point in snow melt. As such, the interesting trends in snow packs might not have even started yet, or barely begun.
There is a tendency to assume that trends are linear, and curves are normally distributed. It is prudent when feedbacks are in play to look for inflection points and non-normal curves. We won’t know for a few more years, of course, but I have the increasing sense that we have entered a warming acceleration phase unseen before and entirely unanticipated. The trend might still be linear (we pray it is so!) but I sense the slope of the line is moving and not in our favor.
In some ways this is an engineering issue, i.e. “Are the dams still suitable for the current climate?” Many dams in the PNW were designed using snowpack/stream flow data from the period 1920 to 1950. So the real question is: “Is snowpack/stream flow data in the period 1976 – 2006 similar to the 1920 to 1950 data?
Re#29: Yes, if precipitation does not change, the annual water balance will not be largely affected (there may be increased evapotranspiration). But the timing of streamflow is a lot more critical than you think. With a diminishing snowpack, this means more of the streamflow will be shifted earlier in the year because you no longer have as much snowmelt. Thus, to maintain the water balance, more streamflow is expected in the winter and less in the summer. And then you can ask yourself, when do humans consume the most amount of water? Answer: during the hot summer when agricultural irrigation takes place. So unless you plan on building more and more reservoirs (which is just infeasible at some point), we have a major issue to deal with. Many researchers have been looking at this issue for a long time (check out work done by Dennis Lettenmaier at U. of WA or Jay Lund at UC-Davis for instance). People are working on solutions but it will by no means be easy and a lot of sacrifices will need to be made. It is definitely something to be concerned about.
Re#33: This is another important issue that has been getting a lot of attention in the hydrology community over the last decade or more. Our flood control infrastructure is designed under the assumption that the flood record is consistent with a stationary time-series. In other words, climate does not change.
There have also been trend analysis studies for the Mississippi River, Yangtze River, and I think several others. See Milly et al. (2006, Nature (415): 514-517) for a look at this issue on a global scale.
Re # 31 “The Columbia River system starts in the Columbia Ice Field in Alberta. Are there any studies showing that critical ice field is shrinking? ”
From the Parks Canada Jasper National Park website:
Because of a warming climate, the Athabasca Glacier has been receding or melting for the last 125 years. Losing half its volume and retreating more than 1.5 kms, the shrinking glacier has left a moonscape of rocky moraines in its wake.
It needs to be clarified here, that it is hypothetically possible to get more snowfall and snowpack in a globally warming world (at least for a while), due to increased precipitation (which is predicted in a warming world, esp for the higher latitudes) coming down as snow. Also not all places are warming in lock-step; it’s the average temp that going up, and (I think) it’s even possible there could be greater variance or extremes (hotter hots, colder colds), as the average continues to go up (but I’m no scientist, and I don’t really know).
So, an increased snowpack would not disprove global warming.
OTOH, these decreasing snowpacks and decreasing glaciers around the world, it seems, is one of the most serious harms from AGW, since, for instance, 40% of India and 40% of China (& and many, many others) depend on the yearly glacial cycle of summer meltwater supplying their waterways during their growing seasons, and snows replenishing the glaciers during winter. If the precip comes as rain or fast-melting snow during the winter, causing flooding, and the glaciers are all melted, with no water for agriculture or drinking, that’s a recipe for big disaster.
Now, I think the debate should shift to which harm from AGW will be greater. Let’s get to it & make such a ruckus no one can even hear the contrarians anymore.
Comment by Lynn Vincentnathan — 20 Mar 2007 @ 3:21 PM
Re. 31 Mr. Lenihan,
[[Based upon empirical knowledge the alleged declining snow pack is is not abnormal. We skiers know.]]
Ok, I’ll bite.
Your comments are blatently not scientific and demonstrate common red herrings often used by people with a political agenda.
Firstly, Results need to be openly analyzed for truthfulness in the world-wide journal process.
Second, Results need to be analyzed from many different locations to rule out natural local variability. Ie. Perhaps the local winds changed the precipitaion in your local location temporarily, but not other places but are not representative of the long term average which is being influenced by larger forces.
Non-scientific global warming charlatons for instance, have a website (co2science.org- largely energy funded) that denies GW and “shows” how the GW is not happening because temperature has INCREASED in one city every month.
Scientifically, this is lieing for the two above reasons. One, is it is not necessarily true (sometimes it is blatently against the scientific records that I checked).
Two, you need many different readings from many different locations to determine long-term trends (like AGW [warming]). The Eath cannot heat or cool evenly, which I remember learning as a child.
Many people who use these ridiculous arguments, are either liars or totally ignorant of the scientific process.
In an important way this is like the issue of sea level rise. We know what the endpoint will be, but not how long it will take to get there. The longest time estimate is big trouble. The shortest time estimate is a full blown disaster.
Our wise President Vaclav Klaus has spoken:
“The â�� so called â�� climate change and especially man-made climate change has become one of the most dangerous arguments aimed at distorting human efforts and public policies in the whole world. …”
“… I feel obliged to say that the biggest threat to freedom, democracy, the market economy and prosperity at the beginning of the 21st century is not communism or its various softer variants. Communism was replaced by the threat of ambitious environmentalism. This ideology preaches earth and nature and under the slogans of their protection â�� similarly to the old Marxists â�� wants to replace the free and spontaneous evolution of mankind by a sort of central (now global) planning of the whole world. …”
More of his worldshaking wisdom is to be found in his “Answers to questions from the House of Representatives of the U.S. Congress, Committee on Energy and Commerce, on the issue of mankindâ��s contribution to global warming and climate change” – here: http://data.zpravy.cz/soubory/ln_domov/A070320_HLM_3.19.07_VACLAV_KLAUS_RESPONSE.PDF
You got your bush, we got our klaus…
Greetings from Prague.
The average snowpack in the Cascades has declined 50 percent since 1950 and will be cut in half again in 30 years if we don’t start addressing the problems of climate change now.
Unfortunately you fail to correct the most obvious howler in this quote: regardless of the numerical details that you discuss at some length, whatever future changes are in store over the next 30 years will happen irrespective of what we do with emissions.
“With global climate change, temperatures in the Arctic stratosphere are expected to continue to decrease …. For every degree of stratospheric cooling, a reduction in ozone of 15 Dobson units can be expected. This sensitivity is three times larger than had been extimated previously from model calculations …..”
This year the snow pack is sufficient to permit summer skiers to ski down to the Lodge at 6000′ in August.
Is there any particular reason Mr. Lenihan failed to mention that the Timberline Ski Area collects and packs down as much snow as they can in spring in order to extend the snowpack below the Palmer Glacier down to the Lodge as long as they possibly can during the summer skiing season?
It’s odd, from his post you’d swear the snowfield he claims disproves the snowpack claim is entirely natural, not manipulated by the ski area …
I work part of each september banding hawks on Bonney Butte, where we have a fine view of the ski area. The snowfield is a rectangle, hmmmm … I wonder why?
A much broader perspective is needed than your memory and a few pictures during one lodge construction period. According to: Lillquist K, Walker K (2006) Historical Glacier and Climate Fluctuations at Mount Hood, Oregon. Arctic, Antarctic, and Alpine Research: Vol. 38, No. 3 pp. 399â��412 between 1901 and 2001 the 5 studied glaciers on Mount Hood are in a clear overall retreat. They have gone through 2 cycles of retreat and advance: retreating during 1901 – 1946 warming, advancing during wet cooling period mid-century, continued retreating during late 1970′s to mid-1990′s warming period, and a slight advance due to high precipitation in late 90′s.
#45, you need to clarify. Are you hence suggesting that we should not do anything? How about the following 30 years? And the 30 years after that?
Comment by Philippe Chantreau — 20 Mar 2007 @ 8:12 PM
Re. #44 David, how representative is Klaus of Czech opinion? Are there a lot of influential people in the Czech Republic who think like him, or is do most Czechs realise he’s two prawns short of a barbeque?
#20 “… people should realize that this snowpack decline is not just isolated to the Pacific NW. The “snowpack reservoir” is absolutely essential to nearly all of western North America.”
… and to Australia’s huge Murray – Darling river basin, now at extreme low-flows after the lightest snowpack year on record in our mountains; data here. Snowpack decline is a global issue, with global consequences.
#40 Columbia Ice Field
It’s happening so fast that you can just about watch it melt in real-time, here.
Re #36: [Thus, to maintain the water balance, more streamflow is expected in the winter and less in the summer. And then you can ask yourself, when do humans consume the most amount of water?]
It might be a good idea to think about other than immediate human needs, too. For most of the western US, most precipitation comes in the winter, and falls as snow in higher elevations. This gradually melts during the summer: in high snowpack years, it’s not unusual to be stepping through remmnants of drifts well into July or even August at the higher elevations. This gradual melting allows the water to soak into the soil, replenishing groundwater & keeping the soil moisture up.
Now if the snowpack melts earlier, the soil might dry out before plants have a chance to complete their reproductive cycles, and so the vegetation might eventually die. Plants shade the soil, and their roots hold it in place. Without the vegetation, the soil gets hotter, accelerating evaporation. When precipitation falls as rain instead of snow, the soil erodes, and now the rain falls on bare rock where it immediately runs off instead of gradually soaking in. You wind up with mountain range that’s desert, except during the frequent flash floods.
The next decade is going to prove to be an interesting one with the issues of global warming and energy.
Wasn’t there a time before automobiles that there was a crisis because of all the horse manure being created because horses were used for transportation? My point is that man is clever enough to make a change, but waits until the last minute to do so. Let’s hope someone invents something soon. In the meantime, pull up a chair and watch the metaphorical train wreck happen before our eyes. Many, many times in history man has existed in deplorable conditions, and the global climate crisis will just be another chapter in our history. Why didn’t the people of pompeii get out of town? Because they couldn’t, and so shall it be with this climate disaster.
For those who need a basic primer on glaciers, retreating glaciers on several continents, climate change in SW Australia, the temperature record for the past 1000 years, and the later arrival of winter snows and earlier melting in the western U.S., and other factors that are touched upon in the Q & A excahanges in the comments above, I would sugggest reading the chapter, Glaciation and Long Term Climate Change, that appears in the 5th edition of Geology and the Environment by Pipkin, Trent, Hazlett and Bierman, Brooks/Cole publisher. The 5th edition has just been printed. It is written for freshman-level, liberal-arts college students and hopefully will be intelligible to those whose comments clearly show a lack of understanding of basic science.
Certainly over 100 years our actions could have a significant influence over climate change. I’m just pointing out that the Mayor of Seattle’s comment contained an obvious error that suggests a limited understanding of the realities of climate change – unless, horrors, he is well-informed but chose to be deliberately misleading in order to defend his policy of spending taxpayers’ money on carbon offsets.
As it happens I live close to a rope tow ski field at about 1300m which hasn’t operated for a couple of years due to lack of snow. And my snarky comment #2 is truthful because coal fired electricity is being used to boost declining hydro. In this case total precipitation seems to be declining as temperature increases here in Tasmania. Since my trick knee is no longer up to skiing I can put up with warmer and wetter weather but what we’re getting so far is warmer and drier.
James Annan (#45) and Paul M. (#55): I’ve never liked the “helpless observer” theory. Our actions can certainly make things worse (e.g. by bringing closer the day where we release natural stores of CO2 and CH4 as a feedback to our own emissions). They can also make things better by slowing growth in energy demand, diversifying energy resources and giving us longer to develop technologies that mitigate climate change and also help us better to deal with its consequences. To say that we do not control our futures is as pernicious as saying there is no climate change–both attitudes foster complacency, and complacency is never a good strategy when civilization is threatened.
[Wasn't there a time before automobiles that there was a crisis because of all the horse manure being created because horses were used for transportation? My point is that man is clever enough to make a change, but waits until the last minute to do so.]
The fact that the invention of the automobile prevented a horse manure crisis in 1900 proves exactly nothing about whether the next environmental crisis can be averted by technology. You just can’t be sure that some nifty invention will save you. In fact the sheer size of the CO2 problem makes it quite unlikely that there will be a simple technical solution.
The reasonable course is to be prudent and limit emissions now. If we do find a technofix, great. But let’s not count on it. It’s like driving off a hill in a car where the brakes don’t work. Never mind, let’s hit the gas anyway! Human ingenuity will certainly find a solution before we hit that brick wall down below, won’t it?
“When one seeks to base an argument on ceteris paribus (all things being equal), it’s a good idea to think it through and make sure the ceteris are in fact paribus.”
My understanding is that the Latin phrase ceteris paribus means “(with) the rest (being) equal.” The ceteris is the same word (different case ending) as cetera in et cetera (“and the rest [of the things in the list]“).
The basic Latin words are:
- ceterus, cetera, ceterum, an adjective or noun meaning “the other, the rest.”
- par, paris, a noun or adjective meaning “equal, like.”
Of course, the idea is a very important one for isolating and then identifying causation. My layman’s idea of experimentation is that it applies the idea of looking at one variable while holding the rest of the factors steady. I would imagine that that is as difficult to do in the climate sciences as it is in my field of interest, history.
Further, I am intrigued by some other similarities between History and the Climate Sciences. They both look mainly at the past, but employ timeless studies (psychology and economics; physics and chemistry, for example) to understand that past. Experts in both fields sometimes use what they have learned about the past to explain current activities and then, sometimes, make predictions about the future.
Likewise, the conclusions of the two sciences stir up support and opposition from philosophical combatants who rightly or wrongly cite those two specialized sciences. For example, in the field of History, questions such as — What was the cause of the rise of Nazism? — bring Leftists and Rights into conflict beyond the strictly scientific question.
Re #61 – “What effect does land use change (e.g. logging) have on snowpack accumulation and/or longevity?” I believe there have been some actual attempts to increase logging in some areas of Colorado as a means to increase runoff. I think this is based on two trains of thought – less vegetation that will use the water in the evapotranspiration process as well as less vegetation to hold/shade the snowpack in place longer into the spring. If my memory serves, test plots showed that this did increase runoff in certain streams, but I am not sure of the ecological consequences of this practice. Based on my set of values, I am highly skeptical and would generally oppose such practices that would artificially increase runoff for human consumption. Based on what has been said about runoff in this thread, I would venture an educated guess that this practice would also increase the chances of flooding and erosion…
Re 64: I stand corrected in my Latin and will paint the corrected version 100 times all around the palace in red paint (a vague reference to an obscure scene in Monty Python’s Life of Bryan).
The controversies in history are probably a little more difficult to resolve than those in science. Even when you have documentary evidence, it may be hard to glean the intent of the author when he/she wrote it.
In science, what constitutes evidence and how much you can trust it is usually a bit more agreed upon, at least within a particular discipline. The oddity in the case of climate change is that contrarians and cranks have been able to ally themselves with entities outside the field who have very deep pockets. This has allowed them to obfuscate the science. There really is no controversy to speak of within the scientific community as to whether climate is changing (It definitely is) or what is largely responsible for causing it (anthropogenic activity). There is more controversy over what will be the consequences–but we are dealing with a chaotic system, and the consequences cannot be predicted with 100% accuracy. Consequently, there is also some disagreement about how forcefully we should respond to this threat. Even Richard Lindzen seems to be in agreement that humans are influencing climate. He merely believes that this chaotic system will somehow restore itself to equilibrium no matter how hard we push it away from its current relative stability. The climate record–and the dynamics of chaotic systems–would seem to disagree with Dr. Lindzen.
In science, what constitutes evidence and how much you can trust it is usually a bit more agreed upon, at least within a particular discipline. The oddity in the case of climate change is that contrarians and cranks have been able to ally themselves with entities outside the field who have very deep pockets. This has allowed them to obfuscate the science. There really is no controversy to speak of within the scientific community…
I don’t wish to divert attention too much from snowpack changes, but you only have to witness what happened (in the UK at least) with the history of asbestos and deep pockets. Science facts hold little sway at times, despite how much you tell people what they don’t want to know.
Clearing forests to increase runoff is downright stupid, and even the proponents of that plan are probably just looking at the money they can make selling the wood. It will increase local runoff, but it will also add massive amounts of silt to the river, which will fill reservoirs and thus reduce their capacity to hold water. Forest removal will also reduce humidity and thus rainfall downwind, which would be the Great Plains. The Great Plains don’t exactly have a surplus of rainfall as it is.
Let us not even talk of the ecological stupidity of that plan or all the CO2 that will be released (many times the CO2 stored in the tree trunks).
I think you guys are missing a great data point. Here in northern Washington State, 12,500 years ago, we were covered with a sheet of ice almost a mile thick. So, simply pick that as your starting point. Now it is indisputable, the ice/snow pack has decreased by, oh what the heck, let’s just round it off to 100%. We’ll have to get very creative now to blame the loss of the first 99.999% of that ice/snow pack on human-contributed causes of global warming. But, with your models and super computers, I’m sure you can figure it out.
- Just trying to help.
I think there is much more to this than the author is suggesting. The trends used in the Mote paper are deceiving… because they are contaminated by interdecadal variability..namely the PDO–the Pacific Decadal Oscillation–which had a maximum (meaning more snow) peaking around 1950 and a minimum in the 90s. Thus, the trend line calculated by Mote suggests a large decrease in snow pack that is not necessarily connected with global warming. In fact, the snowpack has been steady or increasing during the past 20-30 years…a period in which the global warming signal should be largest and in which the PDO signal is of the same sign. Global climate change appears to be increasing precipitation and this may be resulting in overall snowpack holding even if temperatures are warming. Furthermore, the PDO may switch to a snowier regime as would be expected from its typical periodicity. Thus, we may well see the Cascade snowpack being maintained for the next decade or so, until the global warming signal is overwhelming.
Regarding the 50% decrease issue. That number was allowed to stand for over a year and was repeated in other web pages and in a 2004 report to the Governor of Oregon. The meteorological profession must be more careful in the future to insure we are effectively communicating our knowledge and particularly our uncertainties.
Finally, talking to Phil Mote and Dennis Hartmann (chair, atmos sci) and others…it appears that many of us believe that a decrease of 10-15% due to human influence is not unreasonable. This value is within interannual variability and can easily be dealt with by society. 50% loss is a very different matter indeed.
[Response: Cliff. Thanks for dropping in. I agree with you of course that there is a big difference betwen 50% and 10-15%. But in terms of public policy there is an even bigger difference between "no snowpack decline" and "10-15% decrease due to human influence." That's the reason for this post -- to make it clear that the evidence does NOT suppor the position that human influence (a.k.a. "global warming") is a non-issue for considerations of future water supply (not to mention skiing) here in this region. And I don't think anyone has said that the Cascade snowpack will necessarily decline over the next decade. As you know well, the variability on decadal timescales is quite large, and we may even see an increase (as we did in the last few years). No doubt, if that happens, we'll hear all sorts of talk about how "the IPCC had it wrong, global warming is a myth, etc.". That'll be a shame, because it will be dead wrong, but will provide lots of political cover for folks that don't want to take future water resources issues seriously.
Having said all that, I should note that 1) your argument that the last 20-30 years is a "a period in which the global warming signal should be largest" should be interpreteted with caution. The PNW doesn't care about the global mean! If I plot 1977-2006 April SWE, most stations show more snowfall. But many stations show cooling, not warming, over the same period. So there is certainly not the contradiction you imply there is. 2) Your comments on the PDO will also be misleading to many of our readers, because you are implying that there is some predictability in the PDO. But the power spectrum doesn't show periodicity, and one cannot use it to make any sort of predictions. We might get a "run" of 10 years in the positive phase, but then again we might not. I think that Don Percival (also here at UW) has shown this quite clearly. So I have no confidence that the snowpack will either decline nor grow in the next decade. What I have more confidence in is the long term decline. (Though I am sure we both agree that Mayor Nickel's specific prediction that we'll only be at 25% of the "original" snowpack levels by 2047 is not particularly believable, and I probably should have stated this in my post. --eric]
[[I think you guys are missing a great data point. Here in northern Washington State, 12,500 years ago, we were covered with a sheet of ice almost a mile thick. So, simply pick that as your starting point. Now it is indisputable, the ice/snow pack has decreased by, oh what the heck, let's just round it off to 100%. We'll have to get very creative now to blame the loss of the first 99.999% of that ice/snow pack on human-contributed causes of global warming. But, with your models and super computers, I'm sure you can figure it out.]]
And if we start from 1607, we can show that North America is a British Colony.
The implication that we’re warming because we’re coming out of an ice age is wrong no matter how many times you hear it from Rush Limbaugh. We passed the peak of the interglacial 8,000 years ago and the Earth should now be cooling.
RE: 30. I’ve had this preconceived idea that CO2 might not make it up into the upper atmosphere due to it being heavier than most common atmospheric gases. The rational being that in a fire CO2 hangs around on the ground (if you crawl around inside a burning house you choke, if you stand you get burned) possibly due to its density. I was also thinking that CO2 migrates toward the equator due to prevailing winds (no rotation of the Earth considered). If that is not the case, why is it not the case. In other words, how is it that CO2 is making it to the polar regions, it should be stuck in the tropics being devoured by plants at least by that train of thought, did I miss the boat?
[Response: Nice idea, but the gravitational effects on individual molecules in the atmosphere are tiny compared to the forces of all the molecules colliding with each other. So at normal densities and pressures (up to at least the mesosphere) all of the gases are well-mixed - with the exception of water vapour because it condenses as a function of temperature. - gavin]
[Just to clarify this further, CO2 is actually not well mixed on very short timescales. This is what allows CO2 to remain near the ground in a house for example, or to be higher at night in a forest (when trees are respiring) than outside the forest. Think about it -- does the CO2 in burning house stay there forever? Of course not. It eventually esapces the house and mixes with the outside atmosphere. On timescales of months to years, which is all that matters for climate, it is well mixed throughout the troposphere.--eric]
[Response: Another perspective on this: CO2 is heavier than air, and if there weren't mixing it would congregate in a layer near the ground. with an average depth of about 3 meters. Most of us would have to stand on a step ladder to breath, at least near sea level. --raypierre]
Harold, Even if there were no updrafts, etc. CO2 would still make it to the upper atmosphere, if only because the Maxwellian destribution of energies would always have some molecules in the tail that would be energetic enough to rise. Moreover, the density of CO2 is not so high (44 g/mole vs 32 g/mole for O2) that there would be complete segregation.
Most important to remember, though is that Earth’s atmosphere is turbulent. Winds lift dust (much higher density than CO2) and water droplets to great heights. I’m not sure why you think it would move preferentially toward the equator.
RE#69 I referred Ken Coffman an electrical engineer here from another site. He wanted to read my novel but when he found out I was on the other side, this one where the facts are, he was more interested in ad hominems than learning. Just another Imhofe.
RE 74 ty Ray. In response to what I meant about the winds, the sun and the rotation of the Earth give an over all average pattern the movement of the air. The sun for instance causing a majority of the rise of air currents in the tropics causing a general pole to equator movement of air. CO2 being heavier than N2 and O2, with no major updrafts, it would simply lie near the bottom of the atmosphere while the average movement of the air would increase CO2s density at the equator. A major updraft could cause it to rise, but then it would fall back faster than O2 or N2 which would be carried further North and South than CO2. I see your point on the turbulence and take it that gusts would carry CO2 high into the atmosphere but there still should be some stratification of CO2. N2 has 28g/mol while O2 has 32g/mol a bare 4g difference yet still one needs/desires more oxygen while climbing Mt Everest. CO2 is much heavier in that respect (44g/mol as noted in #74) and so there should be even larger differences in its distribution than even O2 and N2. The main question would be, is CO2 evenly distributed at lower altitudes, if so then why, if not then why.
“We passed the peak of the interglacial 8,000 years ago and the Earth should now be cooling.”
Now you’re scaring me, Barton Paul. You’re saying there are impending cooling forces that are completely out of human influence or control? Since I’m far more afraid of cooling than heating, you really have my attention now. What are we going to do to survive when the ice caps beigin growing again? Should we really push for more warming now to delay or reduce the impact of the cooling? I suppose we could use nuclear power plants to stay warm. How about drilling heat pipes to our hot core? We’d better get busy now. I work for a company that does green power and support for the more efficient LED lighting, what are you guys doing? I don’t think there is any time to waste.
Remember also, that areas that were shaded snow pack under dense forest inthe lower Cascades 50 or 80 years ago, have been logged, and turned into roads, malls, parking lots, and housing. Suburbia does not have snow pack. Thus, less snow pack, particularly at low altitudes.
More auto traffic means more soot and dust which deposits on snow and increases early spring melting. Thus, there is less snow pack.
The problem is not with the precipitation, the problem is that the snow is melting before it can be measured as “snow pack.”
Great, now Mark York is checking in. Excellent. Hi Mark. You can see I’ve followed your advice and I’m reading up on the science on this site and trying to stretch my limited intellect to follow the issues and absorb the wisdom. I definitely have an open mind on these topics. Convection, radiation, energy storage. I can’t wait for the test.
Re 77: The reason one needs O2 on Everest is because the atmospheric density itself declines, not just O2 decreases. To a first approximation (ideal gas equation) the density (n/V) will decline roughly linearly with pressure (of course temperature also declines, too). No, I don’t know of any rotating system with an energy input where the fluids stay stratified by density.
Re 69. Somewhere, buried in almost any post is a point trying to find its way out. I believe the point to be found in this point is that different climate drivers are important in different epochs. The deglaciation of the current interglacial is understood to have occurred due to increased insolation. But snow pack was a pretty stable source of water for the duration humans have inhabited the Northwest. That is now changing, and increased insolation cannot be the cause, since the Sun’s output has not significantly increased. Mr. Coffman seems to be implying that the development is not significant, but it is very significant to those living in the Northwest. And perhaps you could attribute it to fluctuations were it not happing at sites all around the globe–the Pacific Northwest, the Alps, Tasmania and New Zealand, the Himmalayas… And indeed it is part of a larger trend–dates of first and last frost are moving closer together–again globally. So, thank you Ken for making that point.
“He wanted to read my novel but when he found out I was on the other side, this one where the facts are, he was more interested in ad hominems than learning. Just another Imhofe.” – Mark York
Now Mark, please be nice. You accuse me of using ad hominem attacks, but I haven’t. I only said I think you’re a funny guy. And, I suggested, if you apply yourself, you could be like George Soros and do the world some good. That is not name-calling.  And above, I’m an Imhofe. I don’t think these are persuasive elements of effective arguments.
I apologize if I suggested the wrong role model. I can substitute Al Gore or Bill Joy, if either accurately reflect your ambition. Or, pick your own, I’d be very interested.
Re #77: Ken Coffman — The first possible date for a try at a stade (ice sheets) would have been in 20,000 years. Probably this will be missed due to anthropogenic warming. The next try is then 50,000 years from now. Probably this will be missed for the same reason. So even if we do our best to stop warming the globe, the next stade won’t be for 150,000 years.
I think you are worried about entirely the wrong thing.
Comment by David B. Benson — 21 Mar 2007 @ 5:26 PM
Re 78: When were we due for the next ice age in the absence of global warming.
The Wikipedia entry on the Milankovitch cycles is well written and directly addresses this point. (Milankovitch cycles are the cyclic changes to Earths orbit, angle to the sun etc. – over tens of thousands of years – that determine the amount of incoming sunlight and it’s angle to the poles, and which are thought to pace the glacial/interglacial ages.)
A model of the effect of the Milankovitch cycles on the Earth’s climate described the 2002 paper in science by Berger & Loutre “Climate: An exceptionally long interglacial ahead?”, predicts a possible ice age in 50,000 year time (in the absence of anthropologically enhanced CO2).
Re#82 There are systems that stratify but under controlled conditions and not for long, some sort of alcholic beverage. I looked up some things concerning CO2, due to its 44g/mol it tends not to mix and pours like a liquid. But it does eventually mix, somthing about Brownian motion and diffusion, so its possible that it could hang around the source of CO2 emission areas for a period of time before dispersing. diffusion “things move from regions of high concentration to low concentration”. So I guess CO2 cannot be ruled out as the main cause of global warming :?
There is a very interesting article talking about the mantel of the earth being exposed to the ocean. Could the ice be melting due to the earth warming the oceans with its missing Crust? Warmer ocean waters will change weather patterns. Just an interesting look at another aspect or reason why the ice is melting, and what could be causing or contributing to global warming.
[Response: Uhhh.. No. The sun provides us with roughy 340 Watts/m2 of the earth's surface. The flux of heat from the earth itself is less than 0.1 W/m2. Not even close to being important! Locally of course, it matters a lot (sitting on top of a volcano for instance). But climate doesn't care about very localized heat sources.--eric]
Re #85: It would seem so but actually I’ve another scenario thought up, though I’m not sure how realistic it is. Methane is considered the runner up in the green house gas gas. I’m not sure that that is the case. There was an article not long ago concerning CO2 causing the ice to move. The problem with it is that CO2 was only found in the later ice ages and not in earlier ones. Back to diffusion, natural gas being very light would diffuse quickly upwards, possibly forming a pure layer of natural gas (due to its high rate of diffusion), and eventually break down, either oxidizing slowly or quickly. If it burned over the polar regions heated CO2 and H2O (a hot acid rain?) could be sucked down on to the polar caps (depending stratosphereic conditions) thus leaving a high concentration of CO2 in the ice as well as heating the air, sort of like a household propane heater using forced air. Might the natural gas only start to form in large quantities on the Earth, showing up in the atmosphere late in the greenhouse game, explaining the CO2 being missing prior to whatever maxim it was found in?
I’m no fan of “helpless observers” but I’m also no fan of gesture politics, and without claiming that science always has the answer I do think that policy decisions should at least have a passing acquaintance with whatever relevant facts are known. If the projected decline in snowpack over the next 30 years is thought likely to have serious effects on water, power, tourism, Yeti or whatever then the Mayor would be well advised to look for real solutions rather than engaging in tokenism.
FWIW I’m also not keen on such hyperbole as “civilisation is threatened” but I’ll let that pass without comment this time :-)
Re: #88: I believe there is something much more sinister at work. I was alerted to this during a bicycle trip through the Canadian Rockies and past the moonscape of Athabasca Glacier last summer. Apparently, Arctic Ice (Arctic Ice Co.) is being shipped to grocery stores across Canada and elsewhere, and sold to thousands of unsuspecting customers, cubed and in plastic bags. Obviously, this is also why Arctic ice is disappearing much faster than Antarctic ice. ;)
Re #78: [Since I'm far more afraid of cooling than heating, you really have my attention now. What are we going to do to survive when the ice caps beigin growing again?]
Stake a claim on some of the continental shelf uncovered by the lowering sea level :-)
Seriously, I think it’s been argued that by a standard of total biological productivity, the Earth is actually better off during an Ice Age. Cooler ocean waters are more productive (due to upwelling which replenishes nutrients in the upper layers), areas like the Great Basin & Sahara become savanna instead of desert, the area uncovered by the lowering sea level more than compensates for what’s covered by ice sheets, etc.
Off topic, sorry. According to this Raw Story article V.P. Cheney may have been personally involved in censoring climate change reports. Seems surprising that the source of the info is supposedly Environment & Energy Daily. Isn’t that M&M’s bastion?
[[CO2 being heavier than N2 and O2, with no major updrafts, it would simply lie near the bottom of the atmosphere while the average movement of the air would increase CO2s density at the equator. A major updraft could cause it to rise, but then it would fall back faster than O2 or N2 which would be carried further North and South than CO2. I see your point on the turbulence and take it that gusts would carry CO2 high into the atmosphere but there still should be some stratification of CO2.]]
Your intuition is leading you astray here. CO2 is well mixed throughout the troposphere. You have to drop a theory if it doesn’t match the evidence.
[["We passed the peak of the interglacial 8,000 years ago and the Earth should now be cooling."
Now you're scaring me, Barton Paul. You're saying there are impending cooling forces that are completely out of human influence or control? Since I'm far more afraid of cooling than heating, you really have my attention now. What are we going to do to survive when the ice caps beigin growing again? Should we really push for more warming now to delay or reduce the impact of the cooling? I suppose we could use nuclear power plants to stay warm. How about drilling heat pipes to our hot core? We'd better get busy now. I work for a company that does green power and support for the more efficient LED lighting, what are you guys doing? I don't think there is any time to waste. ]]
1. It would take 20,000 to 50,000 years for the next ice age to start, so there is no imminent danger.
2. Global warming has eliminated the likelihood of another ice age altogether. That was the point of my post. The Earth should be cooling (very gradually), but is warming because we’re pumping so much greenhouse gas into the atmosphere.
Re 88: Elijah, the energy exchange is too local–and therefore to limited to be having a global effect. I do wonder though whether it might not be a significant source of nutrient upwelling into the more productive shallow depths of the ocean.
#90 Harold, again, in a turbulent system, things tend not to stratify. Look at Saturn and Jupiter where Hydrogen mixes with methane, etc. Still the release of large amounts methane is a serious concern, as its absorption spectrum makes it a more efficient ghg (per unit mass) than CO2. Moreover, I think you will find that a column of gas with a concentration of CH4 will absorb the same amount of radiation (to 1st order, neglecting screening), whether the methane is in a column or not. The CH4 and CO2 trapped near the poles is largely due to the large amounts of peat in the permafrost.
Re 92. James Annan, I really do not consider the contention that civilization is threatened by climate change to be hyperbole. You have to remember that civilization is a rather young phenomenon, and I do not think it is a coincidence that civilization’s emergence coincides with a period of exceptional climatic stability that shifted the balance in favor of agriculture and markets/trade over hunter-gatherer economies. Climate change does indeed threaten two mainstays of modern civilization–agriculture and cheap energy.
How does one earn respect around here? Is it IQ? The number of patents your name appears on? The number of books you’ve sold? Measurable success in a technical field? I know, I have to suspend common sense and historical perspective and embrace the conclusions of modeling done by the IPCC. Well, too bad for me, I shall remain willfully retarded in that regard.
It’s true, I’m poking fun. Seriously though, I believe the current interglacial warming of the Holocene era has enabled the rise of our glorious civilization. We’ve been cold for most of the last 160,000 years. I worry about short growing seasons, susceptibility to disease (have you noticed your body fights off infection by feverish heating?) and other cold-climate-related nastiness (not to mention what the cold weather does to my golf game). So, I wonder who will be in charge of the global thermostat? I’d like to lobby for a few more degrees, not only for my comfort level in the Pacific Northwest, but for alleviating the effects of the coming cooling cycles.
The earth goes through cycles of many types. It gets warmer and colder. Right now it’s warm and you reap the benefits of that luxury. If we humans have some small influence on climate, then perhaps we should redouble our efforts toward warming. The more sane response to climate change, in my mind, is to adapt. Use our brain power and technology to create new forms of energy and work on using it effectively.
This is a non sequitur, but a mantra we should recite routinely. Correlation is not causation. Just a thought for the day.
[Response: Please keep comments substantive. Name calling will just be deleted (as I have above). -gavin]
Re 99: Ken, several skeptics have earned respect in this forum–at least from most of the participants. They have done so by being knowledgeable about issues, by keeping their comments substantive and by realizing that when an intelligent person devotes 20-30 years of his or her life to studying a subject, their views on that subject are worthy of consideration if not acceptance.
It is true that correlation is not causation, but correlation plus a well understood physical mechanism makes a much stronger argument for causation.
You call for development of new technologies to mitigate the effects of climate change. In such a call, you would find many allies in this forum. My own position is that given the magnitudes of the likely changes we will be confronting, and given the difficulty of predicting a chaotic system, anything we can do to slow the onset of these changes and give ourselves more time to adapt represents a wise investment. I’m afraid that I agree that we will not stop climate change. We can make it worse, however, and by extension, I hope we can also make it better.
This forum represents a valuable resource. I am far from an expert–my field is radiation effects in semiconductors–so I am learning a lot from the time I spend here. I also learn from the skeptics that can present their arguments in a respectful tone. You can contribute more to the discussion by eloquently stating your own position, rather than attacking those of others.
“The Seattle city mayor, Greg Nickels (a well known advocate for city-based CO2 reduction initiatives) wrote in an Op-Ed piece in the Seattle Times that
‘The average snowpack in the Cascades has declined 50 percent since 1950 and will be cut in half again in 30 years if we don’t start addressing the problems of climate change now. That snow not only provides our drinking water, it powers the hydroelectric dams that keep our lights on.’”
Greg Nickels recently proposed replacing the Alaska Way Viaduct in Seattle with an underground freeway. It is inconsistent to advocate for measures to reduce greenhouse gas emissions and at the same time promote projects that will not mitigate these emissions, but most certainly increase them – in this case a proposal to replace the Alaskan Way Viaduct with a tunnel.
Voters in Seattle recently rejected his proposal, as well as one to build an elevated freeway.
“Likewise, Seattle is debating what to do about the earthquake-damaged Alaska Way Viaduct on its waterfront. An active citizen’s movement and one of the local newspapers says that the Alaska Way should not be rebuilt; it should be replaced by surface streets and transit. But Washington’s governor has run a referendum that just lets voters choose between an elevated freeway and an underground freeway, and Seattle’s Mayor, Greg Nickels, supports the underground freeway.
Nickels has taken many minor steps to reduce greenhouse gas emissions in Seattle. If he would back freeway removal and more balanced transportation, he could make Seattle into a leader in fighting global warming – an example for the rest of the country and the world to imitate.
Instead, Nickels has backed an alternative that hides the traffic but does nothing to reduce the region’s auto dependency and carbon dioxide emissions. He has not learned anything from the huge cost overruns of Boston’s Big Dig. And he does not realize that, as global warming causes sea levels to rise, his underground waterfront freeway could turn into the world’s largest underground swimming pool.”
[Response: In fairness to Nickel's the State put him in something of a bind by saying that any plan that didn't move 100,000 cars a day was a non-starter. Happily, the voters said NO to both the Big Dig and the Viaduct rebuild option, and now Nickels and Governer Gregoire are starting to talk seriously about public transit. If the people lead the leaders will follow, goes the saying.--eric]
I hope the RC folks discuss Mark Lynas’s new book, SIX DEGREES (National Geographic, 2007). He doesn’t have ice melting from both poles until a 5 degree increase in warming; but he does mention a big portion of fresh water loss (incl glacial water) with only a 1C increase, which apparently is already in the pipes as James Annan alludes to(#45), even if we halt all our GHG emissions immediately (which is impossible).
Here is a brief summary of what happens at each of the 6 Degrees (I think the worst case projected upper warming limit (re both highest emissions & highest sensitivity) for 2100 is now 6.4C):
1C INCREASE: Ice-free sea absorbs ?more heat and accelerates global warming; fresh water lost from a third of the worldâ??s surface; low-lying coastlines flooded.
2C INCREASE: Europeans dying of heatstroke; forests ravaged by fire; stressed plants beginning to emit carbon rather than absorbing it; a third of all species face extinction.
3C INCREASE: Carbon release from vegetation and soils ?speeds global warming; death of the Amazon rainforest; super-hurricanes hit coastal cities; starvation in Africa.
4C INCREASE: Runaway thaw of permafrost makes global warming unstoppable; much of Britain made uninhabitable by severe flooding; Mediterranean region abandoned.
5C INCREASE: Methane from ocean floor accelerates global warming; ice gone from both poles; humans migrate in search of food and try vainly to live like animals off the land.
6C INCREASE: Life on Earth ends with apocalyptic storms, flash floods, hydrogen sulphide gas and methane fireballs racing across the globe with the power of atomic bombs; only fungi survive.
Chance of avoiding six degrees of global warming: zero if the rise passes five degrees, by which time all feedbacks will be running out of control.
[Response: Now THIS is alarmism and it is not supported by science! The Earth has been much warmer than 6 degrees above its present value in the past. I haven't seen Lynas's book, but if this is really a quote from it I don't have any plans to read it, and even less to recommend it to anyone else!--eric]
Comment by Lynn Vincentnathan — 22 Mar 2007 @ 6:40 PM
I guess you can just pick a date to start with and get a different result.
Here is the snowpack charts from 1879 to 2005 and from 1915 to 2005 for two Washington state locations from the University of Washington.
I would think that Nickels should check out the active earthquake faults in the area (the Seattle Fault for example). Puget Sound has had tsunamis in the past. The underground waterfront freeway could become a swimming pool very fast.
Is the Donner Summit from the Donner Party fame (that had to resort to cannibalism to survive)?
Comment by Lynn Vincentnathan — 22 Mar 2007 @ 10:02 PM
Having data on the European Alps, the Andes, the Himalayas, Kilimanjaro as well as the Pacific Northwest matters when discussing global warming – for example, the press release could have pointed out that this is a global trend in many different parts of the world, not just in the Pacific Northwest.
Alaska in 2100 will maintain but 64 percent of its year 2000 snowpack. In Europe, the Alps will be at 61 percent and Scandinavia 56 percent. The Sierras, Cascades and southern Rockies will be at 57 percent of current levels. The Andes will drop to 45. And Mt. Cook and its snowcapped neighbors in New Zealand will be much less scenic at 16 percent of current.
(So if the prediction for 2100 is for 57% reduction, and currently there is a 15-30% reduction, it seems that model behavior still generally agrees with observations)
However, the model seems to be missing other trends:
Ghan cautioned about “significant limitations” to the model. For example, field observations in Africa suggest the famous snows of Mt. Kilimanjaro will be gone within decades, and on Greenland signs point to accelerated snow and ice melt.
“This climate model doesn’t show that,” Ghan said. “That doesn’t mean Kilimanjaro and Greenland aren’t in trouble. But our model doesn’t account for all of the snow loss that is possible. Our model neglects downward flow of snow by avalanches and snow slides, glacial creep in places where snowfall is heavy and the snow doesn’t have time to melt.”
Re #105: Well, Lynn, you said earlier that it was OK to lie to exaggerate global warming (except for scientists). Now you found someone who did it. That “Six Degrees” stuff is complete and utter rubbish, and certainly does not represent even the most extreme end of the IPCC consensus.
The earth was 10 degrees warmer during the Cretaceous and had much higher levels of carbon dioxide, and life did not end in “apocalyptic storms, flash floods, hydrogen sulphide gas and methane fireballs racing across the globe with the power of atomic bombs”, and more than fungi survived.
This kind of apocalyptic fantasy only damages serious efforts to get people to take global warming seriously. Denialists love this sort of thing, it makes their opponents look like idiots.
[Response: Thanks! Yes, you are right on the makr. -eric]
Straw man. We have a vast, complex, world-wide civilization with nearly 6.5 billion of us depending upon that civilization functioning smoothly. How many deaths from hunger is an acceptable price to pay for Hummers and chilled air in the summer time?
Re 112: While I agree alarmism is not productive, the fact remains that nobody can predict the outcome of the current warming epoch, precisely because climate is a chaotic system. This lends itself to projection by everybody of either their fondest hopes (a greener world crap) or their worst fears (the day after tomorrow crap). By looking at paleoclimatic reconstructions, we can glean some possible outcomes, but this still leaves a broad range of possibilities. I do agree that life on Earth will persist, but given that the infrastructure of civilization has never experienced an epoch of change like the present, we have to be concerned with its resilience in the face of such unpredictable change.
2) Your comments on the PDO will also be misleading to many of our readers, because you are implying that there is some predictability in the PDO. But the power spectrum doesn’t show periodicity, and one cannot use it to make any sort of predictions. We might get a “run” of 10 years in the positive phase, but then again we might not. I think that Don Percival (also here at UW) has shown this quite clearly.
This comment is itself misleading, unfortunately. There is little predictability (beyond about a year) for the PDO, but whatever part of the snowpack change is “due” (really correlated with) the PDO is likely a natural swing. This was the point Cliff was getting at. Yes, it doesn’t have to swing back the other ways necessarily, because the PDO is neither truly decadal nor an oscillation. But to the extent it represents decadal ENSO variability, and to the extent that neither the PDO nor ENSO regions have experienced any significant trend over the last 100 years (whereas virtually the entire remainder of the Pacific basin has), you can’t brush off Cliff’s comment so easily.
[Response: I was by no means brushing off Cliff's comment. He brings up the importance of the large variabilty that has nothing to do with "global warming" and he is right. In my view, the extent to which the average decline in snowpack is attributable to such variability is unclear but it is certainly a significant fraction -- very likely more than 50%. However, a big difference between the "natural varibilty" and the forced (anthropogenic change) is that the first is not very predictable. So the best prediction will be a snowpack decline, +/- some big number due to that natural variabilty. The further out we go, the less important it becomes that the +/- is a big number. That is essentially what Cliff said, and I agree. Now, what Cliff specifically said was this: "Furthermore, the PDO may switch to a snowier regime as would be expected from its typical periodicity. Thus, we may well see the Cascade snowpack being maintained for the next decade or so, until the global warming signal is overwhelming." I agree with this entirely with the caveat that there is not enough data to say anyting meaningful about the "typical periodicity" of the PDO. It is reasonable of course to say that we may have "more snow" due to a shift in the mean PDO state, but it is equally true that the PDO may "switch to a less snowy regime". --eric]
Re $112: [The earth was 10 degrees warmer during the Cretaceous and had much higher levels of carbon dioxide...]
Those conditions developed over many millions of years. Rates of change are important too: if you don’t think so, consider the difference between stopping your car by gently applying the brakes, and crashing it into a concrete wall :-)
For a possible example, consider methane hydrates. If they had existed prior to the Cretaceous, a gradual warming would have released them slowly, the CH4 would have oxidized, and so there would have been only trace amounts of CH4 at any time. In a rapidly warming world, they might be released quickly enough to allow much higher atmospheric concentrations to accumulate.
Yep. Fill the bathtub with a slow trickle while the drain’s leaking a bit —- get a steady state where what’s added matches what’s subtracted. That’s the natural state, where CO2 and methane and other organic material are cycling.
Turn up the tap to add water faster to that bathtub, and it’s going to overflow.
The rate of change from burning fossil fuels is faster than natural recycling —CO2 has gone up in the atmosphere by 30 percent in the last couple of centuries since we started burning coal and oil at a great rate, and into the oceans fast enough to change the pH. Simple chemistry, nothing complex about this.
You’ve read it here repeatedly. Why act like it’s unfamiliar?
RE #105 (Eric’s response), the quote was from the Sunday Times summarizing some of Mark’s points ( http://www.timesonline.co.uk/tol/news/uk/science/article1480669.ece ), so they may have exaggerated (I’ve ordered SIX DEGREES, but haven’t read it yet). Perhaps it was just a suggestion of the worst of all possible scenarios, and not something very likely.
However, I did read some science articles (not sure where) about toxic hydrogen sulfide releases during some past warming, and also vast methane releases, so I do think that is possible, at least at some level of warming. I also read several months ago that scientists had found that some clathrates are not as deep in the ocean as previously thought. Whether these releases, even on a massive scale, could cause fire balls or mass extinction, might be hard to say (though I understand that there were past periods of mass extinctions, likely associated with GW). I’ve also read about how superanoxia (caused by some warming processes in the past) killed off a lot of sea life. Maybe that applied to the end-Permian 251 mya, so maybe it’s all very speculative.
Nevertheless, I can’t see how scientists can dismiss it out-of-hand as totally impossible, especially given the rapidity of the warming now, with no indication people (on the whole) are going to reduce emissions, but rather just keep increasing them.
[Response: We’re certainly not dismissing it out of hand as impossible. Just not likely. At all! (Note, I’m not saying 6 degrees is that unlikely, just that the extreme consequences of such a rise are unlikely.). One way to tell whether people really have any idea what they’re talking about is looking at whether they say what “will happen” with certainy (e.g. the way Don Easterbrook on Fox News talked about how we are going to soon be on a cooling trend) vs. what “will likely happen” with stated uncertainties (like the IPCC). If Six Degrees reads like it sounds it does, then it sounds rather like the former style … –eric
Comment by Lynn Vincentnathan — 23 Mar 2007 @ 3:34 PM
RE #105 (Eric’s comment), another thing that puzzles me is that a couple of years ago when I speculated on RC that perhaps the warming might go above 6C, say, in future centuries, Andrew Dodds (I believe) corrected me and said that maximum the earth has ever warmed is 6C (above today’s level), and that seems to be it’s natural limit (until the sun gets really hot, I guess).
So how hot has it gotten in the past? And was there a high rate of extinction going on then? Or is it that a 6C increase may cause some harm, but not too much?
[Response: There is nothing to this "natural limit" stuff. There's no magical number. Certainly it has not been 6 degrees warmer than today for millions of years, but I've no doubt it has happened. --eric ]
Comment by Lynn Vincentnathan — 23 Mar 2007 @ 3:51 PM
You might want to check out the following link to answer your questions.
Grain production would be knocked way back by a 6C increase. For every one degree increase over optimal day time growing temperature, wheat production drops by about 10%. Researchers at Lawrence Livermore and Stanford U estimate that GW is cutting grain production by about 40 million metric tons a year currently and that is even wtih more acreage being planted. I haven’t seen the latest numbers, but as of about 3 years ago, the world’s grain supply was near a 30 year low.
I’m familiar with Mark Lynas’s writings & (if I recall) it’s not so much that he says those catastrophic things will happen at 6C warming, but that if we reach 6C warming (by 2100 or 2200 or whenever), then that may set in motion positive feedbacks that will cause even greater warming and worse harms (without even one additional ounce of human GHG emissions). So (I think) he, in consultation with top scientists (and he reads every sci article on GW there is, it seems), considers 6C warming to be sort of a threshhold point at which positive feedbacks become dominant & warming and/or harms increase greatly.
And that there is some threshhold point for positive feedbacks becoming dominant (& irreversible until it stabilizes at a much hotter temp) and that the threshhod might be 6C warming makes sense to me…sort of based on the principle that heat melts ice & there’s ice that has many gigatons of GHGs locked in right now.
But I’d be happy to know this is pretty much well off the plate for the next three centuries. Then all we’d have to worry about is a few degrees of warming, which we supposedly could reduce eventually by reducing our GHG emissions. Of course, it would still be a serious problem requiring much effort to mitigate (that part won’t change).
[Response: Let's just say I don' t lose sleep over this kind of thing.--eric]
Comment by Lynn Vincentnathan — 23 Mar 2007 @ 8:18 PM
Straw man. We have a vast, complex, world-wide civilization with nearly 6.5 billion of us depending upon that civilization functioning smoothly. How many deaths from hunger is an acceptable price to pay for Hummers and chilled air in the summer time?
Straw man sets up the false dichotomy: the “Six Degrees” statement is wrong therefore global warming is an illusion. I am trying to establish the reality of what climate change means, however inconvenient the truth may be.
Three degress of warming takes us back a few million years, while (an unlikely) six degrees takes us back to the Eocene fifty million years ago. The world seemed healthy enough in those times, however it has been correctly pointed out that now we are trying to support a fragile civilization of 6.5 billion people, and the change will occur much more quickly than in the past. There is no question that this will be disruptive, and the faster greenhouse gas emissions rise the worse it will be. But I think any disaster will be more of a social disaster than a natural disaster with fireballs, hypercanes and whatnot. In other words the problem is more the fragility of our civilization than that of nature.
Re #120: “For every one degree increase over optimal day time growing temperature, wheat production drops by about 10%.” So how much does wheat production increase for one degree of warming over a sub-optimal growing temperature? And what is the net balance? It obviously depends on the rate of change, as faster change is harder to adapt to.
All I am asking for is a complete and balanced picture.
From the Mark Lynas website link from the RC ‘Other Opinions’ bar:
“Buried within the newly released IPCC report is an apocalyptic warning: if greenhouse gas emissions continue to rise at current rates, global warming by the end of the century could total 6.4C. The scientists donâ��t say so explicitly, but a rise in temperatures of this magnitude would catapult the planet into an extreme greenhouse state not seen for nearly 100 million years, when dinosaurs grazed on polar rainforests and deserts reached into the heart of Europe. It would cause a mass extinction of almost all life and probably reduce humanity to a few struggling groups of embattled survivors clinging to life near the poles.”
Eric, I just read New Scientist’s review of the Lynas book — which identifies his sources (as extensive, academic, peer reviewed scientific work) and speak well of his work as an attempt to present the current science and talk about what might be expected — as eventual consequences — over the range of possible temperature changes.
From that review, it might be worth looking at the book before judging it by those covering it in the press. It sounds at least worthy of comment on the specifics the author chose to discuss. Pierce does point out that the book misses the recent suggestions that the big ice caps may go not by slow melting but by more rapid disintegration, so understates the possibility researchers have suggested of more and faster problems in that particular regard.
None of us past our teens likely need lose any sleep over any of this, for our own sakes, of course.
The NS review is behind their pay wall, I read the library copy.
The same review also talks about the recent Pilkey book on failures of large scale models — the reviewer presents that too in a very different light than the remarks I’ve read in blogs and US publications — the bad models discussed are things like the cod fishery model (which predicts a continuing harvest, though the fishery has collapsed and isn’t recovering). The flaws are those of political optimism, not bad science.
I don’t know if it’s mentioned, but it reminds me of the US Ag Dep’t's Forest Service model for success in longterm sustainable management through clearcutting, bulldozing and burning everything left, and then planting Ponderosa pines in the dust and gravel. Worked fine in the short term, for corn and wheat.
Again, why has the discussion gone from the scientific cause of global warming to its EFFECTS? We all know that climate has never been constant and that snowpacks etc. have receded and advanced over the last couple of million years. Either snowpacks grow, or shrink. They never stay constant. No one ought be shocked by this.
Melting snowpacks may provide dramatics, but this is not what science is about. Attempts to dramatise, emotionalise or tabloidise the subject only acts as a disservice to science, and thus should be refrained from.
So why is the temperature of the planet going up? If this has already been settled, then what is the point of continuing this blog?
The objective of this blog is to support the thesis of man-made global warming, is it not? Melting snowpacks indicate warming, but do not lend any evidence to their causes.
The focus must remain on what share do man-made greenhouse gases have on climate change when compared to the entire portfolio of factors that influence climate.
[Response: RealClimate is certainly not designed "to support the thesis of man-made global warming". From our "about" page: "RealClimate is a commentary site on climate science by working climate scientists for the interested public and journalists. We aim to provide a quick response to developing stories and provide the context sometimes missing in mainstream commentary." The discussion of snowpack decline would seem to fit that bill rather well. The impacts of climate change are of broad interest for obvious reasons and I think we'd be remiss to restrict the blog entirely to the underlying theory of the causes of climate change.--eric]
Comment by Pierre Gosselin — 24 Mar 2007 @ 6:07 AM
Eric is right.
I think this has more to do with dramatics, magazine sales and fanning panic then it does with real science.
I could also speculate on what happens if a 200m, 500m, 1000m, 2000m etc. diameter meteor strikes the earth. As you know, we’ve been hit before!
Indeed this topic, and snowpacks too, don’t belong in this blog. It’s stuff you sell tabloids with. Let’s focus on the causes, and not the effects.
Comment by Pierre Gosselin — 24 Mar 2007 @ 6:23 AM
One key aspect of changing Pacific NW snowpack this thread has missed is the changing ratio between April 1 snowpack and precipitation. If this ratio rises than more total precipitation is captured as snowpack. If this ratio declines than more rainfall or melting is occuring during the winter season. A comparison of April 1 SWE at five sites in the North Cascades since 1946 Fish Lake, Stevens Pass, Rainy Pass, Lyman Lake and Miners Ridge indicates that mean April 1 SWE has declined 26% during this interval. At both Diablo Dam and Concrete (reliable long term low elevation weather stations) winter precipitation has risen 1% and 3% respectively thus, the cause is not less precipitation. Instead we are seeing more winter rain and melting events. This is evident in the graph linked which compares the ratio of precipitation at Diablo Dam to SWE at the higher altitude stations. The higher the ratio the greater the percentage of precipitation that is retained as snowpack as of April 1. Snowmelt or rain are the only two events that can reduce the ratio. Since most significant melt events accompany rain, this ratio is a good indicator of the increasing amount of rain events at high altitudes during the winter. North Cascade snowpack-ppt ratio North Cascade Snowpack
RE #122, you’ve hit a very important point, Blair. It’s the fragility of civilization. I think of the stock market near “crash” in the 80s caused by a computer glitch, and imagine what if there were some real problems. Okay, if we have a Katrina once in 100 years, we can handle it (though not very well, apparently). But if many of the effects of even 1C or 2C of GW were to occur within a much shorter time frame (& considering that we are currently living off mortgaging the future, as it is), eventually we won’t be able to pay the bills AND maintain our current living standard. Even without GW, considering all sorts of other environmental & non-environmental problems, we’re heading for rough time. Add in some harms from 1C or 2C, it could mean devolving into civil strife even. (How that works, is that people find scapegoats for their misery, then lash out in all directions.)
I was talking with a biologist last night and we discussed how the geologists are so focused on the level of warming, but don’t have a lot of understanding that even small amounts of warming can really disrupt various species, esp the small, but rapid change we are witnessing today.
So small inconsequential changes in one system (air can’t die, anyway), can have enormous impacts as they get translated into other systems. And I think our modern high lifestyle might be as vulnerable (maybe more so) than those baby birds who can’t get worms to eat, because they’re hatching a few weeks too early or something.
Who needs a Cat 6 hurricane, when a Cat 3 will totally flatten the house?
So, Pierre (#126), yes, scientists of all types are quite interested in results, effects. What’s the point of the experiment, if we don’t want to look at the effects? I hope that’s not the next contrarian argument, that we should only look at the warming as the final effect of the GHGs, and not how the warming might impact life on earth.
Comment by Lynn Vincentnathan — 24 Mar 2007 @ 9:34 AM
Has anyone mentioned the density of the snowpack in this thread? Didn’t see any mention of it. Does all snowpack typically assume some constant density? Doesn’t seem likely. Does anyone measure the mass of the snowpack per unit area? If not, why not?
[Response: Much of the data (most, I believe) is based on snow pillows, which depend on mass (it is essentially a pressure transducer), not area. Note though, that if you want the details to read the original research cited in the post.--eric]
Comment by Stephen Pranulis — 24 Mar 2007 @ 9:42 AM
Re #130. As has probably been said earlier somewhere in RC, those people who are most aware of global warming will hopefully be in a better position to deal with its consequences. I posit a human survival trait that brings both sides to this blog to try and predict and influence and sometimes to ignore our collective future. A little like the scientists and the imperial government in Asimov’s Foundation series (the famous science fiction trilogy about scientist-mathematicians foreseeing an approaching and inevitable breakdown of civilization, and taking steps to mitigate the disaster).
Comment by Stephen Pranulis — 24 Mar 2007 @ 10:18 AM
Re editing of my comment #124:
I recognize that RC has the right to edit or censor comments, but I don’t think it is right to edit in a way that could imply a meaning opposite of what I wrote.
Comment by Steve Reynolds — 24 Mar 2007 @ 11:09 AM
I used that Lynas quote pushing my novel Warm Front in the contest at Gather.com not because I believe it, or did anything similar in mine, but to draw attention to the problem. Many readers said they didn’t feel any sense of impending doom. In a novel one starts with a terrible trouble, but my rendition is more about trying to figure out what the problem is; how bad it will get, and some harrowing escapades with what is already happening. Naturally the extensive sceptic community and politicians are involved in trying paper over the whole thing.
Lynas has gone for full blown sci-fi disaster. Like Crichton’s novel it’s the least likely scenario.
I just wanted to respond to Eric’ comments. His point about not being able to predict the PDO is exactly right..in fact, we don’t even know if the PDO is a real oscillation or a residual of other influences. So where are we? It appears that the global change signal in the NW is to increase precipitation (which could increase snowpack), there has not been much warming at all in the region over the past 20-30 years when the global warming signal has become much more evident, and we can’t predict the PDO signal. Essentially we have no idea what the snowpack will do over the next decade or so. Society needs to know this. There are too many implications otherwise by certain politicians and climate impacts groups. Now most of us believe, based on model simulations…including the high resolution model simulations of the joint effort between my group and CIG..that the warming will eventually win. But of course there are manifest uncertainties there.
Regarding the validity of looking at the last 20-30 years, this is not as far fetched as some suggest. At the recent climate workshop at UW, a leading climate researcher at the Climate Analysis Center told me that no one should look at trends of more than 30 years because of the PDO issue and the fact the global warming signal should be very small then. A number of people criticized the use of linear trend analysis, particularly when there is large interdecadal variability.
In short, the whole business needs a careful reexamination and that is exactly what will happen now.
[Response: Cliff. Fair enough. I don't find anything in your comment to disagree with (though I doubt any of us would actually want to "not look at" trends of more than 30 years). Re-examnation is always healthy. Very nice to have you part of this forum. --eric]
Re #131: [Has anyone mentioned the density of the snowpack in this thread? Didn't see any mention of it. Does all snowpack typically assume some constant density?]
Snowpack (at least the Sierra one, with which I’m familiar) is generally measured as snow water equivalent (SWE), the depth of water you’d have if the snow were melted, so as to eliminate concerns about density.
Re: [I haven't seen Lynas's book, but if this is really a quote from it I don't have any plans to read it, and even less to recommend it to anyone else!--eric]
I have read Mark Lynas’s previous book. He is a serious person. He might make mistakes, but I would like to hear what they are and I may not notice them myself. There will be lots of people like me. The book will most certaily be very popular. I was quite surprised with your remark. I do not believe in “science” that says offhand what is impossible if the deductions and evidence is available and has not been read. I do admit that Mark Lynas’s book is not peer reviewed science but still it does refer to serious science.
What does it prove that our globe has been warmer? Nothing at least to me as I am not a scientist in this field. As an perhaps analogous example; it has also been colder with more CO2 than now. You have explained here that situations were different then and we must accept that when situations differ, effects may differ. Why can’t that deduction apply in this case. Mark Lynas certainly may have scientific articles and sound deduction to back his claim. Perhaps Mark Lynas is talking about a longer time frame and runaway effects and the shorthand makes it easy to misinterpret. It may be that he refers to worst case probabilities or partial geographical events. Whatever the case, I surely wish that Mark Lynas is wrong. I will read the book and hope that someone points out where he has made his mistake if this is the case.
Please also understand how it looks if you seem to take joy in reading all sorts of intentional bullshit from the denialist camp and you attack seriously again and again the faulty presentations by people whose claims clearly have no merit. Then you offhand label as an alarmist someone from the other side from one or two lines of text that does not please you. Why not give a review on a sincere and thorough popular attempt by a person who might fault to the other side and give it similar respect. Is it not the attempt here to have an objective handling of all issues. That can only be achieved when treating both sides similarly. Clearly there has been enough talk on the possibility that IPCC has made a mistake to the side of exaggerating the risk. It is strange that it is almost a tabu to talk about the possibility of grave mistake to the other side. Perhaps we think that the risk is already grave enough. And it should, but where is the action. Anyhow – the book will be popular, people will talk about it regardless if it is recommended by Realclimate or not. Hopefully it is analysed here.
#122 [[But I think any disaster will be more of a social disaster than a natural disaster with fireballs, hypercanes and whatnot. In other words the problem is more the fragility of our civilization than that of nature.]]
The sustained peer-reviewed literature would mostly disagree with you about “what you think”.
CURRENT documented changes most likely due to AGW (Human-warming) are literally legion.
Many current biological and other changes are happening now most likely due to AGW- as recorded in a body of evidence in Nature and Science journals at least. (Go to your library to read them.
The oceans are becoming much more acidic due to increases in CO2. This causes shelled animals to have weaker shells.
Corals are massively being destroyed partly due to warming ocean temperatures (More co2 makes weaker coral skeletons as well). They are one of the primary fishing grounds for developing countries.
Animal, fish, bird and plant range/ migration patterns are changing most likely due to warmer temperatures.
On average, they are changing by 600 meters (6 US football fields) poleward yearly. Every ten years, these species are migrating an average upward by about 6 meters (18 feet) in elevation.
Genetic changes are being observed due most likely to the warming in at least certain mosquitos (Wyeomyia smithii).
Whole toad and frog species have disappeared from ranges (and at least one just disappeared completely) in central America due most likely to precipitation and temperature changes due to AGW (human-warming).
In the Arctic, where much of the strongest warming is being observed, due to “polar amplication effects” such as- melting “reflective” ice exposes more light-absorbing dark land/ocean, species are overlapping each other so that one species is being reduced…such as the red fox taking over the habit of the arctic fox.
Mosqitoes are taking over northern habitats such that certain nesting birds are being hurt by them as they try to nest for long periods of times.
Plankton species have been changing their ranges in the Antarctic most likely due to AGW. This is the basic building block for oceanic life of the food chain.
Breeding seasons are changing for certain birds but not as rapidly for their insect food sources, so this delicate counterbalance is being destroyed.
Pinebark beetles are held in check in many places around the world largely by low temperatures. They increase their number of eggs in warmer temperatures.
They are expanding their ranges into whole new areas and whole new tree species most likely due to AGW.
A forest in Alaska the size of New Jersey has been destroyed partly due to the pine bark beetles’ expansion largely due to AGW.
Mosquitoes with Dengue fever at least have climbed elevations most likely due to AGW.
Certain crop species make less protein due to increased carbon dioxide amounts.
I have only listed a few of the observed changes that have stood up under scientific scrutiny in the journals- most likely largely due to AGW.
This isn’t something projected for the future…this is happening NOW after only an average warming of .6 degrees celsius (about 1 degree F.) over the Earth over 100 years measured over thousands of points on Earth…some points cooler…lots of points massively more warmer than this up to 6 degrees F.
“Big balls of fire”…no…but to say “oh, who cares about those animals, fish, birds and plants…it’s not us…”
Well, crops, human health, coral fishing areas, water supplies, human wars, human mass migration all are affected if you experience AGW.
Re #139: Thanks, Jim. The point made by the article is that the large wheat growing area in India is at the southern limit for that crop, and further warming will reduce yields. The compensating gains will be in cooler areas elsewhere. To adapt, they will have to change the strains of wheat, or switch to something else, eg. rice. Not so easy in a relatively poor area. And as always, the faster the change the harder it will be to adapt.
As for drought in the future, I am looking at the chart at the end of the 2007 Summary for Policymakers. The first observation is the large amount of uncertainty. Beyond that, I see a general increase in precipitation with the exception of a band of the sub-tropics. I can see why Europeans in particular are worried about global warming.
I think we should do our best to slow this change down by reducing fossil fuel emissions. But while some areas will suffer, others may come out ahead, and it is not a worldwide disaster. It will be unfortunate if the poorest areas (that did not cause the problem) get hit the hardest.
Re. 141 Blair wrote: “wheat growing area in India is at the southern limit for that crop, and further warming will reduce yields… compensating gains will be in cooler areas elsewhere.
Please be careful with this comment.
Although, this is true …to an extent (most likely for the near-term future of decades), it can be unconsciously misleading to a point of potential severe danger…
Much of the potential “arable” soils of the north start to become very different in composition to the rich soils of the south the further north you go. The soils start to become thinner and less than ideal for crops.
So for a while, northern crops can probably compensate for the loss of crops in the south.
However, lots of projected crop range shifts into Canada and Siberia and other northern areas becomes an exercise in futility as they become potentially less and less productive the farther north you go…even possibly resistant to genetic engineering.
It does not nesessarily mean that these obstacles are insurmountable…but it might become very difficult and time-consuming to achieve if a rapid climate shift occurs…which almost all available robust peer-reviewed evidence shows has happened multiple times- even about 11,000 years ago off the area of the current east coast of the United States at least…
This also applies for tree species’ shifts.
Now let’s get into what some crops do when they are hit with higher co2 levels. Evidence show that some lose some of their protein content and become weaker to pests.
Again genetic engineering can possibly compensate a lot for this…but that takes time that we might not have if a sudden climate shift happens.
So for policy planners to plan policy on this assunption… could literally have fatal consequences in certain potential possible scenarios.
So people have to be careful when they make an assumption that, “Oh, we can replace lost GW crops in the south, with ones to the north.”. It is not potentially a linear replacement.
You might want to check out rice. It’s productivity drops as night time optimal growing temperatures increase (again – 1 degree increase is a 10% decline). Rice production in Japan and rest of SE Asia is down because of that.
Australia was a major wheat exporter. Not this year. Overall, their crop production is down 60% this year and researchers at CSIRO says this is global warming and a sampling of things to come. On top of that, some of the researchers are predicting that the Great Barrier Reef will be dead in about 20 years. The Outer Reef (not affected by pollution) is already 50% dead or dying. The Murray-Darling River system is drying up. Several of their major cities are down to less than a 18 month water supply. So this is a rich country that is going to suffer a large impact.
Most people don’t realize that our central plains (much of our bread basket) could become more desert-like if the rainfall decreased just by a few inches and temperatures warmed by just a few degrees.
We are doing one heck of an uncontrolled experiment and we are the lab rats!
Snowpack relates to precipitation, warm winters, high early runoff followed by late severe drought, soil moisture balance, increased wildfires due to drought, secondary effects of drought on a regional level, etc. The problem seems to be in estimates of how the hydrologic cycle will respond to warming; will you see increased precipitation or not? No increase in precipitation plus warmer temperatures seems to indicate a decrease in the snowpack. For example, a characteristic of El Nino years is the ‘pineapple express’; warm winter storms originating in the subtropical regions dumping more rain than snow, correlated with changing atmospheric circulation. Thus, the record 1997-1998 El Nino was accompanied by a 25% reduction in snowpack across the Northern Rockies and massive rain in the Southwest. Meanwhile, the Sierra snowpack was at 150% of average. What does that mean for predictions of snowpack in a warming world?
If we can’t predict the response of El Nino to global warming, it seems that it’ll be hard to predict the regional effects in the Pacific Northwest, the Southwest and the Rockies – but the trend of increasingly drier conditions across most of the region seems robust; there’s more wildfires, changing patterns of stream runoff and hydrology, and a diminishing snowpack across the Rockies. The PDO signal seems of secondary important to the El Nino signal, and predictions of the how El ino will change in a warming world are still speculative. It’s also worth noting that these cycles have been abused as explanations of warming phenomena – the increase in hurricane intensity and the AMO, the Pacific snowpack changes and the PDO, the warming Alps and the NAO, and claims that the record winter warmth in the US was simply El Nino – these arguments have been publicly used over and over again as explanations for observed global warming trends – a curious coinicidence that they all seem to be in simultaneously ‘increasing modes’.
Under the study’s lower emissions scenario, summer temperatures in California will rise 4 to 5 degrees Fahrenheit by the end of the century. If nothing is done to curb our use of fossil fuels, summer temperatures rise a dramatic 7.5 to 15 degrees Fahrenheit, according to the study…
…The researchers also find that hotter weather triggers reductions in the Sierra Nevada Mountains snowpack, which feeds into California’s streams and reservoirs. By mid-century, the snowpack decline translates into a loss of 2.6 to 4 million acre-feet of water storage. By the end of the century, the snowpack could decline by as much as 30 to 90 percent, depending upon whether emissions are controlled, the study finds.
Lynn, would you say specifically if what you posted is a direct quote from Lynas’s book, or someone’s paraphrase? If anything was left out, there should be an ellipsis — regular academic quotation style.
I’m just puzzled to see the review in New Scientist, by someone who says he read the book, differ so hugely from the comments by people here who say they haven’t read it and don’t want to — based on the material you posted.
Maybe it’s a true and fair quote; maybe it’s accurate but out of context; maybe it’s a paraphrase. I can’t tell. I don’t have the book yet.
“In 2001, the Intergovernmental Panel on Climate Change (IPCC) released a landmark report projecting average global surface temperatures to rise between 1° and 6°C (2° to 10°F) by the end of this century.” (From a baseline in the recent past, right?)
From the intro at marklynas.org:
“… the end of the Permian period, 251 million years ago. For reasons that are still not properly understood, temperatures rose by 6C over just a few thousand years ….”
That appears the worst case; I hope there’s a probability/error range attached to it. And I hope there’s an interpolation to follow based on the 2007 IPCC update.
Moreso, I hope there is a good list of footnotes and sources available or to become available with the book.
Eric’s right, nothing to lose sleep over personally; as far as I know, every “worst case” scenario would occur after everyone alive on Earth now is dead (of old age, more than a century from now).
So, Hank, just to clarify, I understand that you don’t care at all about what happens after you and a few people you know are gone, is that right?
You also seem to imply that a 6 degree change is the highest known and whatever existing IPCC forecast is nothing to be excited about, considering the margin of error; my notion of what happened at the end of the Permian suggests we should not be anywhere close to (or just not far enough from) the changes that took place then.
Seriously, would you wish even those generations coming after “everybody living now is dead” the task to live through an event just comparable to the end-Permian?
I wonder why it is acceptable to consider a comparison between the result of human activity and some of the most severe extinctions this planet has experienced.
Comment by Philippe Chantreau — 24 Mar 2007 @ 9:20 PM
Re #140, 142, 143: That is a lot of information directed my way. I will pick a few points that I have a problem with.
I was not aware that any land plants actually suffered with increased carbon dioxide levels. That surprises me, as these plants evolved under higher CO2 levels than today. Do you have a reference for this? I am not pushing “greening earth” utopia nonsense, but I thought most plants grew somewhat better under higher CO2 levels. This benefit may be offset by other conditions such as warmer temperatures or less rainfall.
I read about the rice story here earlier, but it does not make sense to me. The temperature range for rice growing areas (eg. between Japan and Vietnam) is much greater than recent changes due to warming. Is rice growing in southern regions less productive than in the north? Or are different strains of rice adapted for different temperatures? Can it get too warm to grow rice?
The pine bark beetle is a classic global warming situation. Forests grow very well in the warmer conditions in which northern forests are now suffering, because they have different trees. Ultimately the northern trees will be replaced, but that does not happen instantly, so we are losing vast areas of forest. So this is a problem of transition. But as long as we keep increasing greenhouse gas emissions, we will continue to be in a condition of transition, and losses will continue.
I am more concerned about the oceans than land. It seems that a climate that is good for land is bad for the oceans. Generally (and not in transition) warmer climate and higher CO2 (unless I am wrong about this) are more productive on land. But warmer water holds less oxygen, and ocean acidification by CO2 removes an important base of the food chain. One other factor is the ocean depends on dust from land for nutrients. Increased desert area leads to increased fertilization of the ocean. I don’t know which way global warming will push this, as a warmer world is generally wetter, but it seems sub-tropical deserts may increase in size. Or they may just shift away from the equator.
I don’t think the uncontrolled experiment we are engaging in is a very good idea, and we would be wise to slow this down as much as possible. The point of science is to understand what is going on as accurately as possible, so we can make the best decisions on how to act.
Re #146: “…For reasons that are still not properly understood, temperatures rose by 6C over just a few thousand years ….”
I have read several book on the Permian extinction (eg. Michael J. Benton; Peter Ward) and never heard of this. Probably because the current state of paleoclimate science does not have the resolution to measure such a short interval. If we do not know how quickly CO2 rose in the Paleocene Eocene Thermal Maximum we cannot possibly know it for the Permian.
Like everything else I have seen here associated with Lynas, this is rubbish. As for him being a smart guy who has read all the peer reviewed papers, the same can be said for Michael Creighton. They both appear to be in the same business: science fiction.
Re GW & worst-case scenarios as “nothing to lose sleep over,” I have never been personally afraid of GW, but I’d give my life, my last drop of blood to help mitigate it and get others to do likewise. GW has always been a moral issue with me. I am heartily sorry for participating in the killing and harming of people (and other of Earth’s biota) — now, in 100 years, 200 years, or 100,000 years (when the last few molecules of the CO2 I just emitted today will finally go out of the atmosphere). So there’s no limited time frame of concern for me.
Comment by Lynn Vincentnathan — 24 Mar 2007 @ 10:30 PM
Re #150 effects of elevated CO2 on terrestrial plants
Refer to IPCC Climate Change 2001, section 22.214.171.124 Effects of increasing atmospheric CO2 (http://www.grida.no/climate/ipcc_tar/wg1/102.htm)
In short, the stimulation of photosynthetic carbon fixation by CO2 in terrestrial plants typically reaches a plateau, or even declines, at or below 800-1000 ppm CO2, a level that could be reached in the atmosphere within a century at current rates of anthropogenic CO2 emissions. The precise response will likely vary with the plant species and its mode of photosynthesis (e.g., C3 vs C4 vs CAM), temperature, nutrient and water availability, and probably a host of other ecological and physiological factors.
Also, note that some marine algae do not respond to CO2 fertilization (Royal Society of the UK, 2005, Ocean Acidification Due to Increasing Atmospheric Carbon Dioxide. Section 3.2;http://www.royalsoc.ac.uk/displaypagedoc.asp?id=13539)
As marine phytoplankton provide roughly half of our annual oxygen supply, elevated CO2 levels in the atmosphere and ocean (and resulting ocean acidification) might not be such a great thing.
(I apologize if this response was posted twice – I may have sent it accidentally while composing it the first time.)
So, Philippe, just to clarify, I feel a heavier responsibility for the future beyond my own time horizon, because the science gives me no way to fool myself — I think those of us who lived around the years this last millenium turned will be remembered for the choices we make, and should be making precautionary choices right now.
Seeing the move to speed the removal of ozone-destroying refrigerants, and get them off the markets much faster, is an example of doing it right.
I read Hank’s remark about “personally not losing sleep over the worst case scenario with 6 C warming” purely as a practical recommendation for setting priorities. We will be having trouble enough dealing with (say) 2 C warming. So why worry about an unlikely event that may happen a century after we’re all dead?
Here is some information on additional nutrients (fertilizers) required for wheat under increased CO2. Under a higher CO2 environment, most plants need more nutrients (Duke U found this to be true with a pine forest subjected to higher CO2. Other researchers have found the same thing to be true with other plants).
Re #153: Thanks, Chuck, that is basically how I understood it. There is positive CO2 fertilization on land, but only up to a point, it is not some infinite bonanza. It does not surprise me that the benefits stop around the levels in which plants evolved in the first place. CO2 fertilization in the ocean is much less, and more than offset by acidification.
Re #155: Hank, Lynas was talking about the end-Permian extinction. I think his statement is wrong, or at least unsupportable. The Permian era was so different than today (eg. one super-continent, 2 million km3 of flood basalt) that it does not teach us much about today’s global warming. It is just being used as sensationalism. The Paleocene Eocene Thermal Maximum (PETM) is much more relevant. For example, this Science paper provides evidence for the effects of ocean acidification.
Re #159: Your article claims rice is being grown at the southern end of its range. I would like to see the full relationship between climate and rice productivity. How much does productivity increase as climate cools? It must reach an optimum, then decline.
I’m not sure, but I think it was the sensitivity that narrowed, not the projection (since this latest AR4 IPCC report added in ?? more positive feedbacks ??, and perhaps the greater increase in our emissions).
I believe the high-end projection of the (leaked) AR4 is 6.4C, not 4.5C — which I think is only the high-end sensitivity for 2 X CO2, and they figure there’s a chance it could go above 2 X CO2 (correct me, if I’m wrong). We’ll know for sure soon.
Which still puts the most likely scenario at about 3C increase for 2100. Which is quite bad enough. And even for those who favor a low end scenario, say a 2C increase, we would still have to mitigate mitigate mitigate. I don’t think our required behavior changes whatever the projection; we just have to keep on doing the very best we can to reduce GHGs.
Comment by Lynn Vincentnathan — 25 Mar 2007 @ 8:32 AM
And now back to the topic & “That snow [that will be diminished] … powers the hydroelectric dams that keep our lights on.”
This seems to be another positive feedback here. They will probably have to start using more fossil-fuel based electricity as their hydropower reduces. And buy more ACs for those hot summers. I know people in India are snapping up ACs as fast as they can be produced (even though the cost for a window unit equals several months salary for the typical upper middle class family there).
I wonder if the AR4 took those positive feedbacks into account.
Comment by Lynn Vincentnathan — 25 Mar 2007 @ 8:42 AM
Re #162, Lynn,
“Which still puts the most likely scenario at about 3C increase for 2100″
As a professional futurist, I must disagree. If we accept AR4 and the most likely sensitivity, we must still select from the different economic scenarios. We have currently been following scenario A1FI. The only way you can come up with only 3C increase as the most probable consequence is by predicting another economic scenario as the most probable. I claim there is no scientific merit in this claim. It may be as likely that we fail to change our course fast enough. It is quite difficult to convince billions of people not to consume so much. And as we will travel through turmoil of war and suffering, we will see a lot of shortsighted goalseeking. We will also invent more and more efficient means to burn coal, oil and forests. Jared Diamond’s Collapse showed the reasons why the near and shortsighted have a high probability of winning.
“in reality, we’re now spending a lot of resources and effort to develop what we know is ultimately a dead end. The apologists now say “Yes, but it’s a useful bridge to better sustainability!”
Yes, but. Wouldn’t it have been better to pick a non-dead end technology, and put all those resources into that direction? I think so. And the argument “we’ve got to take action now!” is one that often shuts down discussion.
Greenies are human too- and quite capable of hearing only what we want to. “Hey, I’ve got this figured out, quit bugging me about it!”
I am a scientist by training. One of the basic tenets is – never quit doubting; never quit thinking; never quit looking; even when you’re 95% sure you know an answer.
Are you struggling with questions about how to live green? Should I give up my toilet paper? Should I sell my car?
My very first advice – take a deep breath, and slow down. You don’t have to make these decisions instantly – in fact it will probably be far better if you don’t…..
The CO2Science site SELECTIVELY quotes parts of the study and leaves others out such as how the plant gets thinner. …It is assuming that the American public is too stupid to look up the whole study and will blindly trust the Fossil Fuel industry’s edited version that CO2 is “good for you”…
RE 165, I’ve already reduced my GHGs by half, so I should double them to where they were back in 1990?
OTOH, I have not bought a Prius yet, because I’m waiting for a plug-in hybrid. But on my last move (due to a new job in a new state), I did move close to work and to a place where I could get on 100% wind power.
So, please, everyone, do make the changes that make sense (& even dollars and cents). That should reduce our household GHG emissions across the nation by at least a quarter.
I just don’t see what’s wrong with that.
Comment by Lynn Vincentnathan — 25 Mar 2007 @ 9:49 PM
Bjorn Lomborg, admittedly not a scientist, yet he firmly assured the US Congress that 2.5 degrees will be no problem. They loved it. Well, the Republicans anyway. When you have so-called experts who aren’t outbilling those who are, “Houston we have a problem.”
Eric: Thanks for the explanation of Nickel’s dilemma. I’m in the San Francisco Bay Area and we are lobbying the Metropolitan Transportation Commission to redefine Level of Service (LOS) standards to mean how many people are moved past a point (e.g. an intersection) in a given time, rather than the number of vehicles. This of course would give priority to buses and other forms of mass transit.
RE Mark Lynas’s SIX DEGREES & the Sunday Times summary I quoted above (#105), I got the lowdown from Mark himself, after I emailed him that I had started a fiasco re his new book:
Oh dear – the truth is that I didn’t write that summary, and I don’t think my book really supports it either – don’t suppose there’s any way you could remind people of that? I agree the [Sunday Times] summary does sound alarmist…the book itself discusses all the uncertainties, and is meticulously referenced…
Hope that clarifies that I made a BIG mistake in quoting that article as representative of Mark’s book.
Nevertheless, 6C can’t be much fun, and I still suspect it could likely lead to a dominant positive feedback trend (of spiralling GHG emissions & warming) for centuries, if not millennia — assuming the earth eventually does reach a 6C warming next century or thereafter. I think the main point is, we really don’t want to find out the hard way. We don’t even want to go near there.
[Response: I'm sorry for helping to mis-represent Mark Lynas's book, and I''ll put up a post at some point (after I've looked at the book myself) correcting that. I suppose one might say there is no such thing as bad press, since I might never have heard of the book, and now I feel obliged to buy it! --eric ]]
Comment by Lynn Vincentnathan — 26 Mar 2007 @ 5:44 AM
Re #167: Thank you, Richard. The papers you provide confirm that higher carbon dioxide levels promote plant growth. But some of them also point out that nutritional value of crops does not keep up – the total nutritional value increases slightly but the proportion to crop weight declines.
My point was that higher CO2 levels are a [small] net benefit to plants on land, and should not be in the loss column. Again, this not the case in the ocean. Your information reduces my view of that benefit.
Please notice I did not quote CO2 Science. That source is so biased I consider it worthless, except maybe to locate relevant papers that say something quite different than what they imply. That kind of dishonesty annoys me as much as methane fireballs from 6 degrees of warming.
>105, 145, 145, — the Times list that was misattributed to Mark Lynas, making people think it was Lynas rather than the Times that came up with that scary exaggeration (noting I was confused too even when I tried to find the source, so the error’s in several postings above)
Lynn, thank you _very_much_ for checking directly with the author and posting the correction.
This is one place I really hope the hosts here put ‘pointer to correction’ comments in — pointing to your correct info in 171.
Hope he shows up here. Now that the misinformation about him has been checked and corrected.