Unforced Variations: March 2013 4 Mar 2013 by group A new open thread – hopefully for some new climate science topics…
350 Responses to "Unforced Variations: March 2013"
Good news, now if we could just get China on board…
Edward Greisch says
227 Chuck Hughes: See: “Drought Under Global Warming: a Review” by Aiguo Dai
What it all means is that the price of food goes up over 40 years. I expect a great famine, or that food will be really unaffordable. Read these books: “The Long Summer” by Brian Fagan and “Collapse” by Jared Diamond.
BallyWho wrote: “now if we could just get China on board …”
Not sure who you mean by “we”, but if the USA wants to discourage China from burning coal to generate electricity, one thing we could do is to stop exporting huge amounts of coal, much of it mined on public lands, to China.
Hank Roberts says
> BallyWho says: 21 Mar 2013 at 12:08 AM
your link is to an NPR piece from last year that’s mostly about comparisons by Cathles et al. on the climate effects of burning natural gas compared to coal.
If you ‘oogle on that You’ll find warring press releases, and lots of PR and lobbying, tied to current political fights. Look for comparisons that include the full cost, not just the production cost, and for estimates on leakage. That link is just for hits listing him as an author since 2012, as a place to start.
Bigger issue in my view is:
Should we spend time and money developing fossil fuel projects and technology, knowing we need to abandon them as soon as we can (and so factor in the cost of scrapping all that production and transportation infrastructure.
Or, spend the same money and effort developing new technology that we can keep maintaining over the very long term.
I think there’s a good case to be made for developing the materials needed for the most efficient generators, which operate at the highest possible temperatures. Right now those get heat from combustion of fossil fuel.
Jim Larsen says
251 BallyWho said, “Good news, now if we could just get China on board… http://m.npr.org/news/front/156814490
I suppose “good” is subjective, because I find it to be horrible news. Using their pro-CH4 numbers, replacing an old coal plant which has perhaps 10 years left with a shiny new CH4 plant which will surely last 50 results in:
50 * 0.6 / 10 = a TRIPLING of GHG emissions due to the conversion.
And China IS on board. The plan is to take all the coal that was going to be burned here and emit even more GHGs shipping it to China to get burned anyway. This allows those in charge to print articles that make you feel good while we’re QUADRUPLING the future emissions from our US-sourced fossil power plant food!
All this good news is going to bake us….
David B. Benson says
flxible @250 — Thank you. Growing up in New Mexico I certainly experienced those rains, sometimes thunderstorms, but nobody ever called it the monsoon season.
#253 SA 21 mar 9:56 am
To me, “we” are the negotiators for a world more resilient to climate change. Currently I favor David Victor’s approaches.
WRT Chinese coal exports it’s easy to find an economist who sees that glass as half full:
Although 23 years seems like a long time, it’s small potatoes compared to atmospheric CO2 lifetimes or, FWIW, bringing a billion poor Chinese folk up to 21st century living standards.
or to new technology deployment time for that matter
complex – yes
confusing – you betcha
#254 Hank Roberts 21 Mar 10:02 am
I “read” Epstein et al.
I support such attempts at what is, to say the least, some very difficult analysis
Taking a lead from David Victor — new technologies, even after they have been developed and proven to scientific and engineering satisfaction, still have to be sourced (is there really enough wind in this place), distributed (now let’s see, we need a new power plant right here and here and here…), and deployed (what do you mean it’s not going to fit on the grid).
The times and costs required for success in these follow-on activities – think negotiation – IMO are the main reason we are taking so long to make progress. Development of alternative technologies is just the tip of the iceberg, so to speak.
Nice to hear from you again Hank…
Jim Larsen says
247ish HankR linked to, “Something strange was happening, just not melting at the surface, Scambos says. It turns out that the intense surface melt that occurred last summer — which affected upwards of 97 percent of the Greenland Ice Sheet — left behind unusually warm snow. Heavy snowfall this winter then buried the warmer layers, according to the NSIDC. In addition, there’s some indication that meltwater from the summer remains unfrozen at about 5 meters beneath the surface.”
Just another glitch, perhaps partially caused by the fact that cooling is a dry process while warming is a wet one. Warmth gets pulsed deep into the ice sheet every summer via surface melt and drain, while all winter the GIS stays snuggly warm under a nice blanket of insulating snow.
Jim Larsen says
257ish BallyW linked, “. “This demand for coal in China appears to be long lived.” and “if the United States does not build West Coast ports to ship western coal to Asia, Canada will likely do so,”
Amazing. By taking the conclusion of burning all the coal that is possible as an axiom, they “prove” that our making money off burning coal is environmentally pure. And these folks actually get paid to write….
oh, probably by coal companies. NOW it makes sense.
The question isn’t WHO makes the money off coal, but WHETHER we allow ANYBODY to mine the coal. So far, the answer has been, “Mining coal is profitable without a carbon tax. Thus, mining all coal is REQUIRED.”
Profit = Purity.
Period. There are no other variables.
#255 Jim Larsen 21 Mar 2:29
Thanks for your post but I really don’t understand your estimate. ISTM if we replace one power plant with another that is nearly twice as efficient, we should have less GHG emissions.
The links I supplied in 257 demonstrate that there is still much controversy as to whether the Chinese demand for US coal is sustainable, so maybe the coal won’t “get burned anyway”. That seems to be the sense of the GreenPeace source report at
with its very pessimistic view for long term Chinese economic success.
Sorry, apparently to link (slowly) to the GreenPeace report, you have to link to:
and click on “Endless Coal Myth”
Edward Greisch says
The worst-case and – unfortunately – looking almost certain to happen scenario
By Aaron Franklin
Please, RC, tell me it isn’t so. Or if it is, what desperate measures could stop it.
Kevin McKinney says
#263–Mr. Franklin has a whole lot ‘sposin’ going on there. I think that scotches the ‘looking almost certain to happen’ part. In fact, I’d guess, as a layman, that it’s almost certain *not* to happen the way he lays it out: there’s just too much “if” and “and then” to be very probable.
I’ll admit that it’s unsettling to think that this nightmare scenario probably can’t be firmly ruled out, though.
Hank Roberts says
That’s AMEG stuff, alarmist super-scared ranting, not from a scientist.
Yes, things are very bad. You’re just figuring this out now?
No, their particular bugaboo isn’t the worst problem.
No, burning more methane faster isn’t a solution.
There isn’t a solution, sorry to say. No quick fix.
Nor is a Venus-runaway the direction we’ll go at worst.
Yes, the Arctic sea ice is going away.
It’s going to happen. It’s been happening.
It started decades ago.
We’ve been doing the wrong thing a long time.
Look, that blogger:
Asserts he works for the world’s experts on the Arctic (citations needed);
says they know what he’s posting;
then claims they must agree with his post
because they haven’t told him otherwise.
Could be, might happen, citation needed.
He’s giving a PETM scenario, approximately.
Now, what’s AMEG’s suggested technofix?
Burn more methane faster as quickly as possible.
“Depressurizing” — building a big new gas infrastructure.
Drilling like crazy around the Arctic.
Releasing — for sure — gas that might maybe could be possibly going to be released if we get a PETM, but might not.
Mhmmmm. Is that the smartest best use of the time and money available?
Or would it, maybe, be smarter to be building an infrastructure and hardware and ways of living that can be maintained by those who live _through_ the coming shitstorm — and won’t have to be dismantled and recycled along with all the fossil fuel-burning stuff that’s already obsolete?
And then bloggerguy goes off the rails entirely to the Venus scenario.
Look at the leverage available. We have a problem with too much fossil fuel burned. What should we do?
“… there are levers, or places within a complex system … where a ‘small shift in one thing can produce big changes in everything’ …. most people know where these points are instinctively, but tend to adjust them in the wrong direction.”
Burn more methane faster to fix the situation?
There is no fast sure fix. It’s happening.
We can moderate the problem by stopping burning carbon, dismantling the fossil-fuel-burning technology, emoving our crap from the seashore in advance of the rising ocean instead of leaving it for the ocean to cover — and taking our lumps instead of putting off the pain for our heirs to suffer.
Are we smart enough?
Why, it’s a big universe.
There must be some other intelligent species out there
that’s reached this point
and not screwed up their planet beyond use.
We couldn’t be the first one, could we?
Awfully quiet in this neighborhood of the galaxy, isn’t it?
Maybe it’s up to us.
Hank Roberts says
…” leverage points … people tend to adjust them in the wrong direction …” is from Donnella Meadows, op. cit.
Hank Roberts says
#259 Jim Larsen 21 Mar 9:27pm
You’re right and I agree with you. China and the US both practice Capitalism. For example both recently shut down major solar cell manufacturers for lack of profit.
Coal is cheap, dirty stuff mined all over the world. China and the US both regulate their coal Industries attempting to mitigate harm during extraction, transportation and use. It’s a matter of opinion how effective these regulations will be, but China is trying hard not to emit and has the advantage of all the CC knowledge developed since the US formulated regulations. China has been fairly successful so far but the history of US results is pretty scary.
China is a “developing” nation. US is a “developed” natiion. Since Kyota developing nations should be allowed higher GHG emission rates than developed ones. This is a “fairness” principle giving the developing nations the same kind of leeway to develop, say, their electrical energy programs that US had starting with the rural electricity developing efforts of the WPA 75 years ago. Since half of the CO2 emissions from back then are still circulating around the Earth, this would seem to be just and fair.
If the US can’t give China the carbon credits, the least we can do is to sell them some of our coal, profit not withstanding.
Hank Roberts wrote: “Awfully quiet in this neighborhood of the galaxy, isn’t it?”
Sure it is. We’re like an isolated tribe with stone-age technology, and no knowledge of modern civilization, that bangs on drums to send signals the few miles between our handful of small villages. Listening for the sound of distant drums from far-off villages, and not hearing them, we conclude that there must not be any other villages on Earth.
BallyWho wrote: “If the US can’t give China the carbon credits, the least we can do is to sell them some of our coal, profit not withstanding”
The USA does, in fact, sell a lot of coal to China — at quite a nice profit for the coal corporations, too, since they pay a pittance to mine coal on public lands, and sell it to China for top dollar.
Hank Roberts says
Tom Toles, on intelligence:
“… The thinking here is that cooking vastly increased the usable calories available in a largely inedible landscape…. But controlling it is hard, as anyone who has ever tried to start a fire by rubbing two sticks together is well aware. You’d need a LOT going on to get fire-making reliable if you were a smartish primate. A bigger brain and some language and opposable thumbs and a would all come in pretty handy. So that’s my candidate. We got good at making fires and keeping them going.
“Now we need to learn when it’s time to put them out.”
re coal export from US – The US does not have to export coal to China, Australia is gladly taking care of the Asian market
As for Aaron Franklin’s speculations on AMEG, it’s waaaay too breathless, he should be breating into a paper bag and hiring a copy editor.
Nice paper on subglacial lake prediction
Hank Roberts says
“drainage switches and capture by neighbouring networks”
Under the ice, how would a drainage be captured? changes in the sediment below, or changes in the ice above the moving water?
Jim Larsen says
261ish BallyWho said, “Thanks for your post but I really don’t understand your estimate. ISTM if we replace one power plant with another that is nearly twice as efficient, we should have less GHG emissions.”
Yep, that is certainly one way to look at it. But the planet doesn’t care whether the GHGs were emitted in 2013 or 2073. The argument for yearly emissions reductions misses the point entirely, which is explained by the Trillion Ton Limit (lots out there. Just google Trillion Ton)
Basically, humanity has a set total emissions limit, and the yearly quantity emitted is irrelevant (within reason). Now, the interesting part is that emissions are NOT caused by putting gas in your tank or by burning coal in a power plant, but by BUILDING the power plant or car. Once built, the infrastructure WILL produce CO2 until it wears out. For example, say you want to help the planet so you buy a hybrid. Well, what did you do with the SUV? You sold it?????? Golly, you just INCREASED emissions by adding a vehicle while retaining the SUV on the road, though driven by another driver. (The planet does not care who drives the car) So unless you’re willing to trash-compact that SUV and THEN buy a hybrid, you’re not doing the planet much good. (The trickle down over a decade does help, but please focus on this aspect) Every car built represents a certain amount of emissions, as we don’t trash usable cars, we use them until they are worn out. Once built, SOMEBODY will drive it until it’s too expensive to fix. (Cash For Clunkers is an exception)
The same goes for power plants. It turns out that coal power plants in the USA were massively built perhaps 60 years ago. They have worn out their licenses and would require huge renovations to get their licenses renewed. Thus, from a climate standpoint, they represent almost zero future emissions. The US coal power plant industry is simply irrelevant to climate change because the infrastructure is on the cusp of both wearing out AND becoming illegal.
So your source decided to pretend that coal plants last forever and to use that as a baseline from which to measure brand new CH4 power plants. Well, the planet only cares about total emissions over the next centuryish. So by building a new fossil-fuel car, or a new fossil-fuel power plant you are adding guaranteed emissions. The old coal plants lasted ~70 years. Obviously power plant tech has improved, so the new CH4 plants will surely last even longer. Pretending that building an OPTIONAL CH4 plant is offset by the MANDATORY retirement of an obsolete and worn-out coal plant, well, that’s just a lie. What it is in reality is the creation of a brand-new fossil-fuel era which has NOTHING to do with the old one that MUST end NO MATTER WHAT ELSE WE DO, as coal plants are old and dying.
It’s the baseline. The REAL baseline is “Our coal plants won’t spew much CO2 into the atmosphere over the next 100 years because they’re all at the end of their life.” Thus, there’s very little climate gain involved in closing US coal plants as climatic policy, as opposed to just closing them cuz they’re worn out. You get the SAME result either way. Let them die natural deaths instead of pretending that building new CH4 plants somehow eliminates CO2 emissions from coal plants that are dead anyway.
Two scenarios, both beginning with the REALITY that all our coal plants get closed over the next decadeish:
1. We “replace” coal plants with CH4 plants.
2. We continue to run coal plants until they die.
Now, wait 10 years. In scenario 1, we end up with expensive CH4 plants that simply can’t be closed (profit would be lost) even though solar and wind will be cheaper and don’t kill the planet. In scenario 2, we simply close the coal plants ~10 years from now and replace them with low-carbon sources. Scenario 1 emits TONS of GHGs through construction, and then saves ~40% for a few years, but in every year after 10 (for perhaps half a century), scenario 1 emits GHGs that simply don’t exist under scenario 2. If you’re gonna compare two scenarios, you HAVE to include ALL emissions, not just those in the first 10 years. The first scenario is planetarily and financially ruinous, while the second scenario is logical and cheap and might save the planet.
Mr. Roberts, as i understand, eq. 1-3 describe the hydraulic potential which is not only dependent on bed topo, but also on ice overburden. As icesheet expands or retreats the hydraulic potential contours change, thus changing routing of subglacial drainage.
I see a paper in press by Ruddiman in the Annual Review of Earth and Planetary Sciences (doi: 10.1146/annurev-earth-050212-123944)
I recall a dispute between Broecker and Ruddiman about the cause of a 20ppm increase in atmospheric CO2 over the last 8Kyr or so that Ruddiman attributed to humans and Broecker to oceanic carbonate compensation. Was that question ever settled one way or the other ? Ruddiman doesn’t seem to address the carbonate compensation mechanism in this paper, perhaps he has done so elsewhere ? I am looking at the literature but would appreciate informed comment.
#275 Jim Larsen 22Mar 9:15
Thanks Jim for your very thorough explanation. I believe your detailed analysis is much better than my way over-simplified wind/solar approach.
Looking over the recent AEP settlement it would seem that scenario 1-like replacements will be around for much longer than 10 years. A modified scenario 2-like calculation accounting for 40 years (?) of emissions should be added to account for the replacement – even clean new technology is bound to emit some GHGs.
AEP agreement can be found googling AEP agreement or linking to
Thanks again Jim. I probably would have missed the Sierra 14 year long lawsuit with its favorable results had you not taken the trouble to explain. ISTM we’re headed with you in the right direction, but it’s going to take a wee bit longer than you hope.
If you can get a copy of David Victor’s climate change negotiation book “Global Warming Gridlock – Creating More Effective Strategies for Protecting the Planet”, I think you’d enjoy perusing it. Tough sledding but a pretty complete analysis by an experienced CC negotiator. I recommend it.
David Victor’s CC negotiation book is reviewed at:
Try it, you might like it
Chris Colose says
I have to confess that I’ve never been particularly interested in the controversies surrounding his views, but there are lot of holes in Ruddiman’s story of the Holocene, including the CO2 rise, which almost certainly involves a change in oceanic carbonate chemistry state (to a large extent at least). This isn’t really fully resolved though. I notice that his article in annual Review of Earth and Planetary Sciences doesn’t satisfactorily address several of the criticisms out there in the literature.
Chuck Hughes says
I assume that the unusually cold weather we’re having in the Southern United States is due to the splitting of the Polar Vortex and not a miscalculation on the part of a groundhog. This situation is not well understood by most people. I think I understand it but the comments I’m reading elsewhere are along the lines of, “this proves there is no Climate Change happening.” Of course as it’s being reported by the Weather Channel and other news sources they never mention the word “Climate” no matter what happens. Is there any way to change the public dialogue on this?
The explanation I’m hearing is that all the heat that was absorbed in the Summer and Fall due to the melting ice created a high pressure dome over the Arctic and forced all the cold air South this Winter. Do I have that right? Can anyone give a good explanation of what the Polar Vortex is and how that has an effect on our weather patterns?
It would help if more folks knew how this works, myself included.
An interesting approach is to use methane from landfills (usually just burned off) to power multiple generators. The electricity can be sold by the local government to the power company. Very, very green.
Bill Ruddiman says
Response to #277, 281: For ten years, my central argument has been that the carbonate compensation explanation of the late-Holocene CO2 rise fails to explain the downward CO2 trends during similar intervals early in previous interglaciations. The key driving factors that Broecker hypothesized were much the same back then: ice sheets had retreated, and forests had moved north and stored carbon, yet atmospheric CO2 fell during the intervals when his hypothesis predicts it should have risen. This argument against his hypothesis still stands, and it reappears in my AR EPS article, along with a refutation of the criticism of my hypothesis based on the carbon-isotope composition of CO2.
In recent years, newly emerging archeological data and land-use histories have provided strong bottom-up support for early anthropogenic (pre-industrial) emissions of CO2 and CH4 large enough to explain the upward late Holocene gas trends. This new information was my focus in the AREPS article. For more detail, WH Freeman will publish my new book “Earth Transformed” this coming October.
[Note: direct tests of the carbonate compensation hypothesis based on trends in marine sediments are impossible. No reliable way exists to measure absolute carbonate dissolution, and even if one were developed, limited core coverage would not permit a global calculation.]
The Australian says the Liberal shadow cabinet has been advised to abolish climate research altogether.
For Chuck Hughes: A “simple” explanation of the Polar Vortex – but you may find the Arctic climatatology affecting your weather more complicated.
Thank you for the response, Prof. Ruddiman. I take it then that you remain unconvinced by Prof. Broecker’s argument (Eos,v87,#3,2006) that this interglacial ought be best compared with MIS11 rather than the previous three, due to the difference in patterns of orbital forcings.
I do like the new (to me) detail that you provide on early human forcings, and I look forward to reading the final version of your article.
Hank Roberts says
> trash-compact that [older vehicle]
Yep. You can do that (at least in California)
(I verified this when I last turned in an older vehicle at the junkyard — to make sure they weren’t going to put it back on the road.)
You don’t get as much money as you (or the junkyard) would by reselling it or parting it out. Low income people get $1500/vehicle; us rich folks get $1000/vehicle:
“… You may apply for California’s vehicle retirement program at any time, and for any reason; passing smog check or not.
The goal of the vehicle buy back program is to encourage the removal of older vehicles from California in order to replace them with newer less polluting transportation ….
… The CA Vehicle Buy Back Program is currently operating however delayed due to a high number of applications received…..”
Hank Roberts says
PS, oops, deceived by Google’s putting advertisers first. The above link is bad (it’s somewhat slanted info about availability of the program, combined with an ad steering people to sell their old cars to junkyards instead of get them trashed, if you read all the way down to the bottom of the page).
Damn. Can’t trust Google any more. They really are pushing any site with something to sell or something that hosts advertising up to the top of the search results.
Better source: http://www.arb.ca.gov/msprog/avrp/avrpfaq.htm
(that too needs help, if you read all the way to the bottom of that page it degenerates into not-exactly-English word salad, sigh. Emailed their webmaster. Proofreading the Internet is never, ever done.)
CRUSH your old car!
Six years after an initial judgement that had already taken eight years to win against AEP’s replacement of a coal-fired power plant, a favorable modification was negotiated
All this time and effort for reduction of SO2 emissions, a universally acknowledged harmful pollution. My take, vis-a-vis RC discussions, is that the times involved in “making people change” are very lengthy – much longer than we would appear to expect in our “scientific” discussions of CO2 problems.
As suggested by David Victor in his book on climate change, I believe a bottoms-up approach for GHG emission control should be based on capability. Victor claims this would be more effective and successful than our current top-down by regulations approach. It would seem that much of the world agrees with this experienced International Law negotiator.
See the review for “Global Warming Gridlock – Creating More Effective Strategies for Protecting the Planet”, previously linked.
Curious about easterbrook’s views on ‘committed warming’.
“The idea that there is some additional warming owed, no matter what emissions pathway we follow is incorrect. Zero future emissions means little to no future warming, so future warming depends entirely on future emissions. And while the idea of zero future emissions isn’t policy-relevant (because zero emissions is impossible, at least in the near future), it does have implications for how we discuss policy choices. In particular, it means the idea that CO2 emissions cuts will not have an effect on temperature change for several decades is also incorrect. Every tonne of CO2 emissions avoided has an immediate effect on reducing the temperature response.”
Is he on to something?
Hank Roberts says
Hank Roberts says
Snark got my URL, that should link to: https://www.google.com/search?q=site%3Arealclimate.org+“committed+warming” (fewer without doublequoting the string, more and other similar terms better found searching the two words without double quotes around them.
AA Cory says
Great job – all this focus and dedication was the inspiration for my new book ON THE EIGHTH TIN, which I launched on Amazon Kindle this weekend.
It takes a look at a climate change solution out of left field and may well appeal to your members and followers. Hope you get the chance to check it out.
re: ‘committed warming’
It would seem possible that we can’t answer the “what would happen to the temperature if CO2 emissions…?”
CC leadership published a policy recommendation to operate with cummulative CO2, not emission rates. They state
“…Even given some chosen target for global temperature change, however, it is extremely difficult within the paradigm of greenhouse gas concentration stabilization to define an appropriate policy target for greenhouse gas emissions. The reasons for this are threefold. First, the relationship between emissions and atmospheric concentrations is complex; achieving stabilized concentrations over time would clearly require large emissions reductions, but would also imply continued emissions at a changing level consistent with the level of natural sinks that evolve over time in a manner difficult to quantify [9,10]. Second, the relationship between greenhouse gas concentrations and temperature change is an elusive quantity that has preoccupied climate scientists for several decades. This ‘climate sensitivity’ has been estimated many times, but remains subject to at least a threefold probable uncertainty range which has not narrowed appreciably in 30 years of research . Third, even given some known instantaneous temperature response to increased greenhouse gas concentrations, there is still a considerable lag between the point of atmospheric concentration stabilization and the eventual ‘equilibrium’ climate change. This lag results from the slow adjustment of the ocean and other slowly responding climate system components to the relatively rapidly increasing atmospheric forcing; consequently, the eventual temperature change associated with a given greenhouse gas stabilization level will not be fully realized for many centuries [11,12]…”
so it really may not matter. It certainly would seem to be undecidable at this time.
Hank – your link didn’t bring up the appropriate search results on my browser so did my own and found a couple of realclimate posts that seem to agree with Easterbrook’s assessment (no ‘warming in the pipeline if emissions immediately cease).
But other reasonalbe climate science blogs contend there is warming in the pipeline even if emissions ceased immediately.
IIUC, “zero emissions” and “constant concentration at 2000AD levels” are different things, where the latter requires some smaller volume of emissions annually to maintain the atmospheric concentration. And I had not seen the latter explained til now. Thanks for the encouragement to google.
Hank Roberts says
barry, the blog software here doesn’t like double quotes (some of the time); when you see only part of what ought to be a link appears colored green, try instead copying the whole line and pasting it into your browser’s search box. Or just use the RC search box, top right.
Bill Ruddiman, What would you choose as a co2 baseline in 1850 corresponding to the beginning of the oil age? What uncertainties would you place on that value? The ice core data says 287 ppm but could that number be higher? A slightly higher number by 5 ppm seems to fit the cumulative carbon emissions profile better.
Wan’t to revise the revisionists ? Fred Singer’s shop <a href="http://vvattsupwiththat.blogspot.com/2013/03/suffering-fools-gladly.html"has put out a call for editorial helpers for Part Deux of Heartland 's upside down anti- IPCC report
Bill Ruddiman says
Re #286: Sidd —Several past misconceptions about stage 11 have been upended. [See Rohling et al, EPSL doi:10.1016/j.epsl.2009.12.054 2010; Tzedakis et al., Clim. Past, http://www.clim-past.net/6/131/2010/; Ruddiman et al, The Holocene, doi:10.1177/0959683610387172, 2011].
Stage 11 wasn’t an unusually long (26,000-year) interglaciation, but instead a long warm deglaciation (425-410K), followed by a full interglaciation of less than 10K (410-402K).
Stage 11 isn’t the best Holocene analog. The precession signals were comparably weak, but precession and tilt were out of phase early in stage 11 and in phase early in stage 1. The best (but imperfect) stage 11 analog to the present day was ~398K, by which time CO2 and CH4 values were dropping and sea level was falling, indicating new ice growth.
The best Holocene analog is stage 19, both with weak precession and with tilt and precession in phase. CO2 reached an early-interglacial stage 11 peak of 260 ppm (versus 267 early in stage 1), and then fell continuously for the next 10,000 years to a value (245 ppm) at the top of the 240-245 ppm range predicted by the early anthropogenic hypothesis. Unlike the late Holocene, it did not rise.
Re #297: I favor 285 ppm as the pre-industrial value. High-resolution ice at Law Dome shows CO2 reaching 284 ppm just before 1200 and 283 ppm in the early 1500’s, but falling during the late 1500’s during the American population collapse. The start of the fossil-fuel industrial era near 1850 is the first time CO2 exceeded these earlier (and clearly pre-industrial) values.
Sorry for the bad lik in the above – this should work :
Want to revise the revisionists ?
Fred Singer’s shop has put out a call for editorial helpers for Part Deux of Heartland ‘s upside down anti- IPCC report