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Two degrees

Filed under: — david @ 8 July 2009

The countries of the G8 today approved a target of 2° C rise in global average temperature above the natural, preanthropogenic climate, that they resolve should be avoided. The Europeans have been pushing for 2 degrees as a target maximum temperature for several years, but this is something of a development for the Americans. We posted recently on two new papers about what it would take to limit global average warming, finding that it would require fairly strong change in trajectory. About 2° C as a target, we wrote,

… even a “moderate” warming of 2°C stands a strong chance of provoking drought and storm responses that could challenge civilized society, leading potentially to the conflict and suffering that go with failed states and mass migrations. Global warming of 2°C would leave the Earth warmer than it has been in millions of years, a disruption of climate conditions that have been stable for longer than the history of human agriculture. Given the drought that already afflicts Australia, the crumbling of the sea ice in the Arctic, and the increasing storm damage after only 0.8°C of warming so far, a target of 2°C seems almost cavalier.

Nevertheless, we view today’s development as a constructive step.


411 Responses to “Two degrees”

  1. 151
    llewelly says:

    As a software engineer I’m willing to make a social prediction, if dangerous climate change is averted you can expect a large number of people to claim it was just another “Y2K scam”.

    Here’s my social prediction: if GHG emissions are reduced to zero, but the GHGs already emitted are sufficient to cause dangerous climate change, a large number of people will claim that since dangerous climate change happened anyway, GHG emissions must not have been the cause.

  2. 152
    Mark says:

    re 150.

    Some people think that the Y2K problem was a scam because computers didn’t fail on the swap over the millenium.

    So maybe the answer to that “problem” is to say “sod ‘em” and ignore them.

    You can’t please all of the people all of the time. So do what’s right, even if some will try to knock you down.

  3. 153
    Mark says:

    “its fascinating to see most esteemed people here fixated on the present wind energy technology which is good, but , as you wrote, is cumbersome and takes a lot of land/sea space.”

    What is fascinating is that you think wind takes up a lot of land/sea space.

    There are a lot of farms that lose a small fraction of their land and still use it for farming, the only loss being the rather small footprint of the upright tower. Though they cannot be placed close together, that is because the turbines are wide. But they don’t go anywhere near the ground.

    Fascinating that you have to make up a problem and can’t find a real one to use.

  4. 154

    Agreeably, a 2C target is a step in the right direction. Education is still critical. The 350ppm target by Hansen is also a good target but as I recall he mentioned something about “possibly lower” as part of the consideration.

    Education remains critical to understanding for people and policy makers. A point I have been trying to get across is that it’s not about believing in AGW, it’s about understanding the mechanisms involved. Believing always leads to a rhetorical argument. Understanding leads to appropriate action in the way people view the energy they use and they way they influence policy makers through their votes.

    So progress has been made, but we all just need to keep learning as best we ca. and helping inform others.

  5. 155
    Mark says:

    “Understanding leads to appropriate action in the way people view the energy they use and they way they influence policy makers through their votes.”

    But the debate is steered into belief to ensure there IS no understanding.

    And it’s being done by those who, for whatever reason, do not want to think AGW is real or does not want to take the steps necessary to counter it.

    TV today doesn’t want “understanding” either. It wants talking heads. Preferably two. And conflict.

  6. 156

    Mark, I don’t understand your cynical matter of fact argument. But that is nothing new. Some countries don’t have the luxury of vast tracks of lands ( to place the pillars on??? Cappich???) the question of ownership, grid placements, like in the UK, some countries are heavily populated, and many dislike the sight of wind turbines over their landscapes. The fixation over the same generation of horizontal axis turbines to be placed all over the world as the solution is a bit passe, there are other ways to harvest the wind.

  7. 157
    Nick O. says:

    2 degrees seems like rather a lot to me, especially when we take into account how this is predicted to be manifested over the different latitudes (e.g. increases of much more than 2 degrees near the poles). My other concern is that the models generally seem to underpredict the rate of change. It will be interesting to see what happens in Greenland next, I think, and then probably down at Pine Island; we will find out soon enough, anyways.

  8. 158
    RichardC says:

    105 Tharanga says,”If energy source A costs $x/BTU, and energy source B costs $2x/BTU, then you cannot (in the short run) save net money from going from A to B. ”

    You missed the point. The cost of A depends entirely on whether we choose to adopt B. Oil will cost EITHER $150 OR $25 depending on whether we choose to limit fossil fuel demand. That’s $125 worth of savings on the oil side IF and ONLY IF we adopt renewables. Roll that savings into a tax to prevent the market from backsliding and suddenly we have a big pile of money that would have gone to oil. Even now oil is way overpriced. We can drop the price to $25 any time we want through demand modification. Since we’re huge importers of oil, it’s all gravy to the USA, Europe, Japan, et al. Of course, Mideast wars and terrorism will have to find alternative funding, but then that’s dandy with me.

  9. 159
    Edward says:

    Edward #121
    You state “that the average person on Earth won’t understand the need to change until it is too late” and “6.7 Billion people will die on Earth”.

    You are correct, because most of the people on this planet are scratching to make a living and feed their family and probably don’t have an electrical source to even plug in a fridge much less a laptop computer. Their list of concerns don’t include worrying about how much CO2 they are emitting when burning dung to keep warm.

    If given a choice, these “average people” would probably choose access to any energy source even if produced using coal or oil rather than worry about potential climate change 20 to 100 years from now.

    I think it’s presumptuous of the Elite Industrial nations to try and impose their will on the developing world in this regard. If C02 is a problem and USA and developed world truly are concerned about it, then they are welcome to cause as much pain to their economies to correct the problem. Their actions should not depend on what the rest of the world does.

    On an individual basis, how many here are willing to give up their Prius’ and laptops and trade places with a subsistence farmer in India?
    Thanks
    Edward

  10. 160
    Doug Bostrom says:

    Edward Greisch 10 July 2009 at 1:08 AM:

    Edward, let me amend and soften my words, introducing and possibly substituting “feckless” where I’ve already mentioned deception and/or ignorance.

    The vast majority of residential PV systems do not involve batteries at all, they use an arrangement called “grid tie”. DC electricity generated at a residence is used to operate an inverter, which is designed so as to maintain phase with grid-supplied AC. Output from the PV system is thus added to the grid, this output sometimes only offsetting demand from the residence, at other times exceeding local demand and thereby unloading the grid itself by an incremental amount.

    Thanks to the fact that the distribution grid functions using AC, no modifications are required of the grid itself. As the he “pig” on the pole outside a home is a transformer, it functions both “forward” and “backward”.

    Depending on locale, this energy may be purchased by the utility at either wholesale or retail rates. If the local utility has sufficient pull with regulators, in rare cases no compensation is offered for surplus power.

    Surplus power generated by these residential systems offsets required generation capacity for a utility. These systems operate best during periods other than typical base load periods for the utility, so whatever power is sent back into the grid is delivered at an advantageous time for the utility.

    Progressive utilities are assisting customers to the extent they can with these systems, because incrementally capitalizing grid tie can be attractive compared to capitalizing monolithic generation plants and because they do not demand an ongoing input of money for the electricity they generate.

    Personally, I would not make the mistake of ignoring the grid power available where I live, so I’m just going to chuckle in amusement at your “challenge”, which only reflects poorly on you. As it happens, I do pay extra money into my monthly electricity bill, money which is used to capitalize “alternative” energy sources. In the case of my location this money is being used to relieve load from hydroelectricity which supplies something like 80% of electrical power here.

    As to off-grid applications, first let’s emphasize that they represent a tiny fraction of PV installations. Secondly, a properly sized and managed battery bank for these systems will retain some 80% of initial capacity after 5 years’ operation. 80% of capacity is typically considered end-of-life for secondary batteries, though consumer tolerance for degraded performance is generally accepting of worse degradation.

    As to the enormous battery bank you require, that’s because you’re on grid, have evolved your habits to reflect that, and are making an ignorant choice about improving your situation. It’s nothing to do with the viability of PV systems.

    “Only experimental evidence is believable.”

    Pertaining to batteries, see:
    http://linkinghub.elsevier.com/retrieve/pii/S0038092X07000291

    “My credibility is irrelevant.”

    Yes, to the extent that you don’t have any when it comes to this subject.

    But your credibility -is- important in another way. RC is somewhat of a well of clear factual information about climate science and by nearly inevitable connection to a lesser extent about energy topics. Whether making stuff up because you don’t know any better or by presenting erroneous communications for unknown reasons, you’re dropping a dead donkey down the well and polluting it.

  11. 161
    RichardC says:

    147 Mark, I added it up in more detail and I came up with the US spending 8% of the GDP on the military.

  12. 162
    Dan L. says:

    Mark #146 “No, the denialists just don’t bother to listen.

    They mean “it’s saturated, so how can adding more be a problem?”.

    They are ignoring why it is still a problem.”

    Ramanathan & Feng are denialists? Don’t think so.

  13. 163
    Sy says:

    ‘some countries are heavily populated, and many dislike the sight of wind turbines over their landscapes’

    Perhaps these people with such delicate aesthetic sensibilities would prefer to live next to a coal burning power station? Or maybe a nuclear reactor…

    The problem here is that for decades those affluent enough to live in nice areas away from environmental problems such as living near a power station, on inside heavily polluted inner-urban areas have simply done so, externalising the visual and environmental costs of their lifestyle on to people who are poorer than themselves.

    If people are willing to include the total costs (not just a monetary sum) of generating energy in a sustainable way so as to minimise ACC then the most painful measure that will be taken will not be the sight of some windmills on the horizon.

  14. 164
    Mark says:

    “wayne davidson says:
    10 July 2009 at 10:59 AM

    Mark, I don’t understand your cynical matter of fact argument.”

    No, I don’t suppose you do.

    Interferes with your dogma.

    “Some countries don’t have the luxury of vast tracks of lands”

    And such countries therefore have no large volumes of people to protect.

    It’s a lot easier to put a solar panel on a roof and no more space is needed.

    Land that you can’t build on or farm can be used to put wind or solar power collectors on. Are there any countries who have no land that is unsuitable for this AND have used all the land they have up?

    “and many dislike the sight of wind turbines over their landscapes.”

    And many don’t like the sight of power lines. Or factories.

    Dislike won’t kill them and their dislike is more dogmatic (it’s green energy. eeewww) than aesthetic.

    “The fixation over the same generation of horizontal axis turbines to be placed all over the world as the solution is a bit passe”

    Ah, a statement with NOTHING AT ALL to back it up.

    Well done.

  15. 165
    Mark says:

    “On an individual basis, how many here are willing to give up their Prius’ and laptops and trade places with a subsistence farmer in India?”

    Are you one?

    How about you move to the Maldives or the sub-saharan cities if you think that there are more important things to do now than avoid global warming.

  16. 166
    Sy says:

    161….

    The conclusions from Ramanathan and Feng’s 2009 paper are:

    “1) The missing warming: global average TOA forcing of ABCs is about −1.4 Wm−2. The implication is that, when ABCs are eliminated, the surface can warm by about 1.3 °C.

    2) The committed warming: effectively the greenhouse gas increase from pre-industrial to now has committed the planet to a surface warming of 2.4 °C (using IPCCs central value for climate sensitivity), and only about 0.6 °C of this has been realized thus far.

    3) Global dimming: aerosol observations from satellites, surface stations and aircraft (for the 2000–2002 period) suggest that there is a global wide dimming of about −5 Wm−2 due to ABCs. Assuming negligible dimming before 1900s, this result translates into a global dimming trend of −0.5 Wm−2 per decade, with factors of 2 or larger dimming trend over land areas. The ABC induced global mean dimming trend is much smaller than the 3–6 Wm−2 per decade inferred from radiometers over land stations.

    4) ABC impact over Asia: regionally, ABCs may have played a very large role in the widespread decrease in precipitation in Africa and in S. Asia (the Indian summer monsoon) and the widespread retreat of glaciers in the Hindu Kush-Himalaya-Tibetan region. The former is due to dimming and the latter is due to solar heating of elevated layers by ABCs.”

    This is a peer reviewed paper by respected scientists who are saying that aerosol forcing means that the majority of the warming caused by existing co2 emission has effectively been masked thus far, and that as aerosols remain in the atmosphere for far shorter a duration of time than co2, we will have already most likely crossed the 2 degree threshold that the G8 politicians have been discussing this week once the cooling effect of aerosols dissipate.

    That really doesn’t sound like denialism to me

  17. 167
    SecularAnimist says:

    A couple of comments.

    First, I would suggest to those who hope to influence American public opinion regarding anthropogenic global warming, PLEASE state temperatures and temperature changes in degrees Fahrenheit, rather than degrees Celsius. I understand that Celsius is the standard for science. But Fahrenheit is what Americans are used to hearing in weather reports and weather forecasts, and what they intuitively and viscerally understand.

    When most Americans hear about a 2 degree (Celsius) rise in global average temperatures, it doesn’t sound very significant. So you have to lead them through a scientific, logical, factual chain of explanation and causation as to why that matters. Will they “get it”? Maybe.

    But if you tell them (as per the recent NOAA-led report on expected climate change impacts on the USA) that by century’s end, much of the USA from the southeast up through the vast agricultural lands of the midwest will experience more than 150 days per year (five whole months!) when the temperature doesn’t fall below 90 degrees (Fahrenheit), that makes a much stronger, more intuitive and visceral impression. People “get” what that would be like.

    Second, there are a lot of things said about renewable energy technologies — e.g. solar photovoltaics, concentrating solar thermal, wind, biomass, geothermal, etc — in these threads that reflect ignorance about the actual state of those technologies and industries today. Solar and wind are mature technologies, which at the same time continue to develop rapidly. And the wind and solar industries are booming. The planet’s wind and solar energy resources are vast, and harvesting even a small fraction of that potential can supply far more energy than the world currently uses, sustainably and indefinitely, with tiny environmental impact compared to fossil fuels or nuclear.

    If you want to know what’s really going on with these technologies — e.g. the state of the art of mainstream technology that’s being deployed on large scales today, the new developments and breakthroughs that have the potential to produce even more renewable energy at ever lower cost, the major projects that are now being built or are planned all over the world — then please take advantage of the numerous online resources offered by trade groups like AWEA, or manufacturers, or business-oriented publications that track the renewable energy industry to educate yourself.

    You may be surprised at what you learn. In my experience most people are really unaware of what wind and solar can do, and how fast they are already growing. While the climate situation is far worse than most people think, the options for quickly phasing out fossil fuel and nuclear energy and replacing them with clean renewable energy sources are much better than most people think.

  18. 168
    dhogaza says:

    Dan L

    Ramanathan & Feng are denialists? Don’t think so.

    I skimmed the section you refer to, and what they appear to be discussing is why the forcing response to increasing CFCs is linear, rather than logarithmic as is true for CO2 at concentrations in the atmosphere we see today and will for the foreseeable future.

    Go read the whole section, closely …

    No, the denialists just don’t bother to listen.

    They mean “it’s saturated, so how can adding more be a problem?”.

    They are ignoring why it is still a problem.

    You, too, Mark, since they [R & F, in the paper Dan's asking questions about] say no such thing. It’s obvious you didn’t look at the paper, which isn’t really about CFCs or CO2 anyway, but negative forcing due to aerosols.

    Dan’s question appears to be an honest one, and the section he refers to is a bit poorly worded IMO.

  19. 169
    dhogaza says:

    In fact, Mark, R&F first came up in this thread in a question to you:

    Mark – What are your thoughts about the analysis by Ramanathan and Feng (PNAS, Sept 17,2008: http://dx.doi.org/10.1073/pnas.0803838105), in which they calculate the committed warming of cumulative emissions since the pre-industrial era as in the region of 2.4°C (with a confidence interval of 1.4°C to 4.3°C), based on calculating the equilibrium temperature if GHG concentrations are held at 2005 levels into the future.

    R & F discuss our already being committed to a 2.4C rise without adding any more GHGs at all, and the text I blockquoted above is in essence asking how can we limit global warming to 2C if we’re already committed to 2.4C, i.e. if R&F are right.

    Sounds like your tarring them as being denialists, or lashing out at Dan for asking an honest question about a statement they make in their section 2.6, is a bit unkind, at best.

  20. 170
    Mark says:

    re 169, If R&F is right, then we have already broken the 2C limit.

    How could it be otherwise?

    If R&F are wrong, maybe not.

    But if we’ve broken 2C limit, so what?

    Give up and party like it’s 1999?

    It’s kind of a pointless question, which is why I’m so sharp about it.

  21. 171
    Edward says:

    #165 Mark
    I think we should be cautious putting demands on nations and people who have not enjoyed our standard of living for the last 50-60 years. I think China makes a good point when they make the argument that since the developed countries have pushed CO2 up to it’s current 389 ppm level the developed countries should bear the burden of correcting the problem. In the meantime, China and India are interested in improving living conditions and the standard of living for their people by making cheap energy available. If that energy is most easily provided by the coal or oil resources they have available to them so be it. It’s all the more reason that developed countries have to innovate renewables and get them to the point where they can provide energy cheaper than oil or coal. At that point India and China will have an economic reason to begin making the transition to a Lower CO2 economy.

    One last point, it’s not likely that huge oil producing countries in the middle east will allow their main source of income to become obsolete and “stay in the ground”. I would expect the price of oil to fall to stay competitive with renewables which will forstall the rate of transition to low CO2 economies.

    If the USA had taken Hansen’s advice back in the late 1980′s and gone on a crash program of building next generation nukes there was probably a chance we could be exporting that technology now to China and India and it might have prevented the commissioning of many of the new coal power plants they are building.

    Given the reluctance to take action back then, I cannot forsee a scenario where CO2 stays below the 450 or even 500ppm level. There’s just too much inertia in coal and oil and too much incentive to make sure all of it comes out of the ground.

    In the meantime, I’m fine driving my Chevy Conversion van, living nearby a nuclear power plant and enjoying the comforts of AC and the use of a wireless laptop.
    Thanks
    Edward

  22. 172
    Mark says:

    “You, too, Mark, since they [R & F, in the paper Dan's asking questions about] say no such thing.”

    May I point you to 145.

    Query:

    “where as the CO2 absorption is close to saturation since their concentration is about 300,000 times larger.”

    Saturation is irrelevant to CO2 having an effect.

    Denialists think it is central.

    So maybe you should go back to 145 and see whether the quote is taken out of context, yes.

  23. 173
    Chris Dudley says:

    David (in #22),

    Sorry, in my #41 I got your name wrong.

  24. 174
    Mark says:

    PS what would be the point of asking the question “if this paper says we’re already over 2C, is it possible that we won’t be able to keep under 2C”?

    Is this a rhetorical thing?

    It’s like asking “If I ate all the pies, would there be no pies left for you?”

    Patently silly.

  25. 175
    dhogaza says:

    Give up and party like it’s 1999?

    It’s kind of a pointless question, which is why I’m so sharp about it.

    Well, “party like it’s 1999″ isn’t the reaction a sane person would make, and I don’t see anything in the thread above suggesting that’s the response of anyone posting here.

    Obviously, the response would be that we’ve got to work even harder to reduce CO2 emissions, while simultaneously facing up to the need for more mitigation that is being thought about in a 2C-rise world.

  26. 176
    dhogaza says:

    So maybe you should go back to 145 and see whether the quote is taken out of context, yes.

    The section’s rather poorly written and there’s nothing explicit embedding the statement in a “logarithmic response to increased CO2″ context.

    So Dan L asked in post 145 …

    Eh? Having learned at the feet of the wise here in RC, I thought we had debunked the s word. Do R and F mean something else?

    An honest question deserving of an honest response (I already laid out the “something else” above, at least as I read it) rather than abuse. He found the statement confusing. He asked for clarification. Labeling R&F as being “denialists” was not a clarifying response.

    OK, I’m done with this. Feel free to yell scornfully at me if it will make you feel better.

  27. 177
    James says:

    Edward Greisch says (10 July 2009 at 1:08 AM)

    “To maintain your current lifestyle, you are going to need a lot more batteries than you can afford. I did the calculation for the current price of lead-acid batteries. My house would need $50,000 worth, given my air conditioning bill, etc.”

    Why not start by examining your basic assumptions? Take the one about maintaining your current lifestyle: do you really think the way you live now is perfect and unchangeable? Or, to take your example, with a little thought, some insulation, and a few shade trees, might you not be able to reduce that air conditioning bill?

    That’s really the first piece of advice that a reputable solar installer will give to people contemplating an OTG system: redesign your lifestyle to minimize energy use. Then instead of $50K worth of batteries, you’d only need $5K. Then think about storage other than batteries, such as flywheels…

  28. 178
    dhogaza says:

    Mark:

    Is this a rhetorical thing?

    No, the poster at 13 asked your opinion of the paper, wondering if you think their 2.4C figure is plausible or not. Something tells me he won’t be doing that again .,..

    It’s like asking “If I ate all the pies, would there be no pies left for you?”

    Patently silly.

    Not at all, if we can’t contain warming to 2C then mitigation planning should assume warming greater than 2C. Whether or the warming can be contained to the 2C level proposed by the G8 seems to be a rather important question, to me. Regardless of whether or not a simple answer suffices.

  29. 179
    David Schofield says:

    Ray Ladbury says:

    “Fully 90% of scientists publishing on climate related topics and vurtually all the evidence say the globe is warming and that we’re the cause.”

    Interestingly this may be only 84% not 90%, and only 70% who think it’s a serious problem.

    http://www.guardian.co.uk/environment/2009/jul/09/climate-change-debate-human-activity

    [Response: Wrong. Please re-read the above sentence, in particular "scientists publishing on climate related topics" (i.e. those most likely to be familiar with the current state of the science). That is not what is reflected by the poll quoted in the Guardian. By the way, the actual number (98%--i.e. Oreskes) is actually higher than 90% as a previous commenter already noted above. -mike]

  30. 180
    Jim Bouldin says:

    Animist says:
    First, I would suggest to those who hope to influence American public opinion regarding anthropogenic global warming, PLEASE state temperatures and temperature changes in degrees Fahrenheit, rather than degrees Celsius. I understand that Celsius is the standard for science. But Fahrenheit is what Americans are used to hearing in weather reports and weather forecasts, and what they intuitively and viscerally understand.

    Chu did exactly that in his Senate testimony yesterday as he illustrated one possible future scenario by comparing it to the difference between the last glacial maximum and now (11 degrees F I think it was).

  31. 181
    RichardC says:

    164 Mark says about [and many dislike the sight of wind turbines over their landscapes.],

    “And many don’t like the sight of power lines. Or factories. Dislike won’t kill them and their dislike is more dogmatic (it’s green energy. eeewww) than aesthetic.”

    I agree. Wind turbines are drop-dead gorgeous. The spacing required ensures that they don’t become a visual blight, and their slow white turning just thrills the soul. They are silent, beautiful, and effective. If only most neighbours could be so good.

  32. 182
    Chris Colose says:

    I don’t follow the policy stuff a whole lot (especially at the local, state levels), but I was wondering if anyone was familiar with some recent stories about Arizona looking to outlaw legislation that relied on climate change projections. See some of the first several links at http://www.google.com/search?hl=en&q=%22arizona%22+AND+%22climate+change%22+AND+%22legislation%22+AND+%222009%22&aq=f&oq=&aqi=

    Not a lot of credible sources I could find, but it did come to my attention so I was wondering if this is a big deal?

  33. 183
  34. 184
    RichardC says:

    182 Chris, it’s a non-law. Since laws take precedence from last to first, any law prohibiting future laws is just a political pout.

  35. 185
    Doug Bostrom says:

    Chris Colose 10 Jul 2009 at 4:27 pm:

    Does not seem unlikely. AZ has at least one state Senator on record (last month) as saying that Earth is already 6,000 years old, got along with environmental regulations for that long, thus does not need environmental regulations.

    Anything’s possible when your brainpan has been dessicated to jerky by standing out in the noonday Arizona sun.

  36. 186
    David B. Benson says:

    Chris Dudley (123) — Hansen has (more recently?) stated “350 ppm or lower”. I am under the distnct impression that GIS began melting a little in the 1950s, with CO2 concentrations at about 315 ppm. At that time the Swiss glaciers were melting back about 4 m/yr. Already the last remnants of the Laurentide Ice Sheet on the mainland had melted in the 1930s and 1940s.

  37. 187

    #155 Mark

    Thus the challenge for those who understand it better are tasked with.

    #167 SecularAnimist

    Good idea, to speak to Americans in Fahrenheit.

    #179 David Schofield says

    If one examines the NCAR chart, combined with the evidence it is not improper to say based on the evidentiary record that we are virtually 100% sure that the new path of warming is 100% human caused.

    http://ossfoundation.us/projects/environment/global-warming/natural-variability

    In other words, separate natural variability from the path based on the forcing and accept the fact that we now have natural variability on the new AGW path.

    That’s 100% human caused.

  38. 188
    Rob says:

    OT but there is no Q&A section so I didn’t know were to put it. Also, all relevant threads are closed for further comments. (E.g this one http://www.realclimate.org/index.php/archives/2007/06/a-saturated-gassy-argument/ or this one http://www.realclimate.org/index.php/archives/2007/06/a-saturated-gassy-argument-part-ii/)

    Does planet earth emit any infrared rays in the wavelengths the CO2 is supposed to stop? Or put like this, how does the earth look like from “out there” does its signature/spectrum still contains the wavelengths within the 13-17um band in any significant amount or has most of it already been absorbed by the current CO2 layer? If not, how much is it left for CO2 to absorb.

    /Rob

    [Response: I have an on-line simulator of IR in the air, showing a spectrum of the outgoing IR to space, that I use for teaching and my textbook. The model server is here. David]

  39. 189
    dhogaza says:

    182 Chris, it’s a non-law. Since laws take precedence from last to first, any law prohibiting future laws is just a political pout.

    Did you read what they’re actually passing? The bill will prohibit the state equivalent of DEQ from *enforcing* any law that mentions global warming.

    It doesn’t attempt to forbid the *passing* of furture laws that mention global warming. They may be scientifically illiterate but at least someone there knows enough about the law to pass something that will stick.

    Still, it’s mostly symbolic. AZ isn’t likely to pass any law regarding global warming that would require state DEQ enforcement anyway. The claim that they can use this law to fight federal legislation is farfetched.

  40. 190
    David B. Benson says:

    Rob (188) — I suggest seeing if what you want is in Ray Pierrehumbert’s

    http://geosci.uchicago.edu/~rtp1/ClimateBook/ClimateBook.html

  41. 191
    Hank Roberts says:

    Rob, CO2 doesn’t “stop” infrared. CO2 and other greenhouse gases absorb infrared photons; the energy gets moved around, some gets transferred to non-greenhouse gases by collisions, and so on. If you’re thinking of the notion that CO2 might be “saturated” and so increasing CO2 wouldn’t cause more warming, that’s long debunked. Look up “saturation” in the search box.

    If you’re wondering about the weather satellite photographs in various bands, there are some that show clouds, others that show the ground, some that can image CO2 and other gases in the atmosphere at various heights.

  42. 192
    RichardC says:

    189 dhogaza said, “Did you read what they’re actually passing? The bill will prohibit the state equivalent of DEQ from *enforcing* any law that mentions global warming.”

    so the future law simply has to say that the equivalent of DEQ *MUST* enforce the future law.

  43. 193
    dhogaza says:

    so the future law simply has to say that the equivalent of DEQ *MUST* enforce the future law.

    Yes, but that’s more difficult. Laws in place are harder to overturn than floating hot air balloons that aren’t law.

    It’s called politics

  44. 194
    Patrick 027 says:

    Rob (188) – I second David B. Benson’s suggestion (191), and what Hank Roberts said (192) – see also some comments made here: http://www.realclimate.org/index.php/archives/2009/06/groundhog-day-2/
    (some comments – most of these are mine but a few aren’t:
    370-372,(374 Barton Paul Levenson),382,

    463 (middle of comment – re 425,454)

    604, (622 Chris Colose),
    759,
    ***764***
    792,
    958 (see link)
    978
    (Hank Roberts 918 links to (Kiehl and?) Trenberth)

    1004,1045
    1048-1049,1066

    1063,

    1070 (Chris Colose),
    1071)

  45. 195

    I am not a climate scientist, my physics career ended at differential calculus. I am an electrical contractor, so I feel qualified to answer Edward Greisch.

    Here on the Hilo side of Hawaii Island we average 280 days a year with measurable rain. I mention that so you are not under the impression that we get massive amounts of sunshine.

    I can install a stand alone solar system for a small cabin for $5,000.00. For $50,000.00 you can get a really good system, enough for a 2,500 square foot house with a swimming pool (I just did one) which includes batteries and and an automatic start generator.

    A grid tied system without batteries can be done for between $8,000.00 and $20,000.00, depending on the size needed. These are real world numbers.

  46. 196
    Patrick 027 says:

    Re 188 – but the short answer:

    Earth still radiates significantly to space even in the central portion of the CO2 band (near 15 microns). Adding CO2 does not (at least not before the climate response, which is generally stratospheric cooling and surface and tropospheric warming for increasing greenhouse gases) decrease the radiation to space in the central portion of the band because at those wavelengths, CO2 is so opaque that much or most radiation to space is coming from the stratosphere, and adding CO2 increases the heights from which radiation is able to reach space, and the stratospheric temperatures generally increase with increasing height. This does not translate into greater net upward radiation at the tropopause, however. Meanwhile, farther out from 15 microns, CO2 is not yet sufficient to make the stratosphere so opaque, and much radiation comes from below the tropopause, from where temperature generally decreases with height. Adding CO2 increases the height distribution from where radiation can escape to space, so the Earth looks colder to space at wavelengths where the effect is not already saturated at the tropopause level. There is some added complexity in that downward radiation from the stratosphere will increase at wavelengths where CO2 is not saturated, but what is especially important is that the net upward radiation at the tropopause level decreases with increasing CO2 (true both before and after stratospheric equilibration (adjustment of straospheric temperatures to radiative equilibrium given the forcing but before tropospheric and surface response), but with a quantitative change), with contributions to this effect coming mainly from two wavelength intervals on either side of the central part of the band at 15 microns. Further increasing CO2 saturates a wider central part of the band but brings wavelengths farther out from the center of the band into the interval of significant CO2 opacity, so there is still an effect. Tropopause-level forcing is particularly important because the way the temperature varies with height in the troposphere is shaped by convection so that the temperatures at different vertical locations are coupled by convection and tend to go up and down together – this includes the surface (uncoupled variations in temperature will tend to change the rates of convection so as to bring the temperatures back into a relationship shaped by convection). There are some variations from that general pattern due to convection patterns and changes in convection.

  47. 197
    Patrick 027 says:

    “There are some variations from that general pattern due to convection patterns and changes in convection.”

    … and other feedbacks.

  48. 198
    Patrick 027 says:

    Re 188
    see also:
    Kiehl and Trenberth:
    http://www.atmo.arizona.edu/students/courselinks/spring04/atmo451b/pdf/RadiationBudget.pdf

    The work is an estimate of the global average based on a single-column, time-average model of the atmosphere and surface (with some approximations – e.g. the surface is not truly a perfect blackbody in the LW (long-wave) portion of the spectrum (the wavelengths dominated by terrestrial/atmospheric emission, as opposed to SW radiation, dominated by solar radiation), but it can give you a pretty good idea of things (fig 1 shows a spectrum of radiation to space); there is also some comparison to actual measurements.

  49. 199
  50. 200
    Chris Dudley says:

    Richard (#184),

    In the Constitution there are some constraints on future laws. For example, no law is allowed that establishes a religion or prohibits the free exercise of a religion. Presumably, that can be changed by Constitutional Convention, though I don’t see how congress could propose a repeal to the states. Prohibition on Bills of Attainder or ex post facto laws is also in the Constitution.

    So, there are ways that a present law can prevent a future law. In this case, the legislation is requiring a future law rather than agency derived regulation. Sometimes it is hard to feel like you are doing your job if you don’t micromanage.


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