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garythompson at 02:26 AM on 9 March 2011Climate Emergency: Time to Slam on the Brakes
So if I read this post correctly, the reason there appears to be no correlation (over the recent past) between atmospheric CO2 concentration and Temperature anomoly when CO2 is above 370ppm is because "there is further warming in the pipeline".
The oceans are storing up all this heat and once it is released there will be at least a doubling of the warming that the fast feedbacks are producing. When will this release occur? You state that if the current CO2 level remains at the 390ppm level that we'll experience sea level increases of 25 meters. We will most certainly be at and above that CO2 concentration for the forseeable future so what is the predicted year we'll see that 25 meters of sea level rise? There are many dire predictions in this post but they are all many decades out and very ambiguous on when they will happen. Can you be more specific with regard to time scales of say 5 years out?
Moderator Response: We don’t have a good knowledge of the timeframe; that’s one of the scary parts. The question is how fast can the ice sheets respond? On the upside, a 25 meter sea level rise wouldn’t happen overnight; it would probably take at least a few centuries. On the downside, there is a possibility of a few metres of sea level rise this century, and that possibility is looking increasingly likely. Even if Hansen’s ice sheet feedback doesn’t get us, there are still greenhouse gas feedbacks… – James -
hank at 02:13 AM on 9 March 2011Climate sensitivity is low
The prior suggestions are 1) poptech redefining the laws of physics, a notorious outlier shows his stuff everywhere 2) Isaac Held has a blog, finally. If you don't know his name, read some of his papers and look for his rare posts at other climate blogs about his work. Very good news to see him start writing more for the public in this blog form. 3) Stoat on Spencer on climate sensitivity: Spencer thinks he can't possibly be wrong, and given that assumption, what else can explain why he's so alone? -
Fred Staples at 02:12 AM on 9 March 2011Climate Emergency: Time to Slam on the Brakes
Harry Seaward is quite right. The West in general, and the UK in particular, have enjoyed the benefits of an industrial revolution, which the East now seeks to emulate. It might be interesting to compare the direct evidence, the atmospheric temperature and CO2 records to see if it likely that China and India (or Amrica for that matter) might be persuaded to abandon carbon fuels. The Central England Temperature, measured by thermometers, illuminates the AGW argument. Anyone looking at he overall plot will be struck by the very modest rise in overall temperatures from 1659 to 1979, 320 years. In that time the CO2 concentratiom increased from 280 ppm to 350ppm, with almost no discernible increase in temperature. A linear regression actually gives the rate of increase at 0.19 degrees C per century - per century, not per decade. Between 1980 and 2010 the rate increased very sharply, to almost 3 degrees C per century, while CO2 increased from 350 to 385 ppm. The AGW alarm sounded and has reverberated ever since in blogs like this. Now statistics as a subject is silent about the future, and we cannot project either of these two rates. But if annual temperatures fall back from an average of 10.36 in the decade ending 2009 to the 9.54 average in the decade ending 1979, the AGW alarm will fall silent. Last year the average temperature was 8.83 degrees C, the 90th coldest year in the record, exactly the same as the temperature in the first year of the record, 1659. December, 2010, was the second coldest December. -
hank at 02:09 AM on 9 March 2011Climate sensitivity is low
wups, lost the comment part, sorry. Suggesting a look at this site, which is trying a grade-school-level approach (well, for a very scientifically literate grade school population). Worth a look given the amount of confusion shown in the comments. "... ... we explain what a greenhouse gas does. The two spectra are crucial to the understanding of the role of greenhouse gases in the atmosphere..... ... ... The next simulated spectra are those for 380 ppmv and 760 ppmv of CO2 respectively looking down from an altitude of 70 km and hopefully show the slight broadening of the 'well' that is crucial to the understanding of why more CO2 leads to a little more warming, even though such warming might not be measureable...." -
RickG at 02:07 AM on 9 March 2011Climate Emergency: Time to Slam on the Brakes
Gilles, Have you not been directed to the thread, "CO2 lags temperature"? I suggest reading the Intermediate article and trying to understand its content. CO2 can be both a forcing and an feedback. -
muoncounter at 02:02 AM on 9 March 2011Interactive animation of the climate change impact on agriculture
johnd "were derived from enclosure studies conducted approximately 20 years ago." Note the word 'studies.' "the "food for thought" is really all about the adequacy or otherwise of the models being used as benchmarks." You are picking out the word 'models' and objecting to it without noting that there are data from long-term studies behind those models. I'm neither a farmer nor a botanist (and the squirrels got most of last summer's tomatoes), but I quickly found 2 papers (refs above) casting doubt on the accuracy of greenhouse-based yield projections against actual performance in the open fields. The Ville came up with another. Thus it cannot be conclusively said that increased CO2 is a good thing; perhaps the simplest statement on the question of CO2 means higher plant yield is: 'the science isn't settled.' -
Harry Seaward at 01:58 AM on 9 March 2011Climate Emergency: Time to Slam on the Brakes
The industrialized nations rely on fossil fuels to a large degree. It is a convenient form of portable power. Developing nations are also increasingly become dependent on fossil fuels as they develop infrastructure to improve the quality of life for their citizens. Until (read when and if) solar, wind, wave, or other forms of "clean" energy become reliable and readily available, fossil fuels are going to rule the roost. Nuclear has been maligned to the point that it will take major changes in public perception to put in place. -
Gilles at 01:52 AM on 9 March 2011Climate Emergency: Time to Slam on the Brakes
RickG, do you mean that the poles can experience a 6°C decrease in temperature (e.g. between -140 000 and -120 000 BP) , without any change in the global temperatures ? Interesting ... but still CO2 hasn't decreased in this period, so what did change in the forcings ? if you look in detail, you will see many periods lasting several centuries during which temperature and CO2 varied in opposite ways; this is obviously contradictory with "Temperature can vary only through a change in forcings AND CO2 is the main driver for these changes AND the relaxation timescale is less than one century". -
RickG at 00:20 AM on 9 March 2011Climate Emergency: Time to Slam on the Brakes
#23 Gilles, Note what was said, "at the poles", not global. We are already seeing that much increase in the high latitudes. -
Bob Tisdale at 23:57 PM on 8 March 2011Blaming the Pacific Decadal Oscillation
The Moderator replied, "[Daniel Bailey] If you feel Tamino used the wrong dataset why have you not corrected him? I note, having read the entire post Tim linked to for you, you were absent from the discussion therein." Most of my comments are deleted at Tamino's OpenMind. You continued, "By definition, Kaplan is THE dataset to use for NA SST's." Kaplan SST data is “A” Sea Surface Temperature anomaly dataset, not “THE” dataset. The ESRL uses Kaplan North Atlantic SST data (0-70N, 80W-0) to create their AMO dataset, similar to JISAO using the obsolete UKMO and obsolete Reynolds OI.v1 and the current Reynolds OI.v2 SST data for their PDO data. In some respects it’s similar to the Met Office using Hadley HADSST2 for their HADCRUT product, and similar to GISS using a combination of HADISST/Reynolds SST for their LOTI product. The ESRL selected a SST dataset to use for their AMO product. They could have used any long-term SST dataset. A question: If you wanted to determine the global sea surface temperature anomaly contribution to the global GISS LOTI data would you use Kaplan SST or the datasets GISS uses? The multidecadal variability of the Kaplan SST data is different than the SST datasets used by GISS and those differences biased Tamino's results. They gave him the result he was looking for, but they were wrong results because he used the wrong SST dataset. I illustrated that error very clearly in the post that I linked earlier. Here’s the address again: http://bobtisdale.blogspot.com/2011/02/comments-on-taminos-amo-post_03.htmlModerator Response: [DB] When it comes to climate-related time series data analysis I trust those who not only do it for a living, but those who's work has proven to not only withstand the tests of time and other research, but who have established gold standards for accuracy and understanding of the underlying physical processes the analysis' represents. Tamino's body of work has long been regarded as the de facto standard in climate data analysis. So a choice between Tamino or you is a non-choice. As to issues with moderation on Tamino's blog, he has come to have little tolerance for those unwilling to learn, but has demonstrated great patience with those trying, but struggling, to do so. -
Gilles at 23:52 PM on 8 March 2011Climate Emergency: Time to Slam on the Brakes
iana@16 : so do you agree that what alan_marshall said : " The pattern is consistent. An increase in CO2 from 180 to 280 ppm is associated with a rise in temperature at the poles of more than 10°C. The increase in CO2 is less than double, yet the increase in temperature is greater than projected for doubled CO2 in medium-term models. I see this as evidence the estimates for climate sensitivity derived from such models are likely to be conservative." is incorrect, since there must be OTHER forcings ? iana@17 : my comment is the following : you can read here http://www.grida.no/publications/other/ipcc%5Fsr/?src=/climate/ipcc/emission/ "No judgment is offered in this report as to the preference for any of the scenarios and they are not assigned probabilities of occurrence..." so can you explain me how to compute probabilistic forecast without any a priori probability distribution of scenarios ? -
newcrusader at 23:47 PM on 8 March 2011Climate Emergency: Time to Slam on the Brakes
One of the uncertainties I have read as a non scientists is 'climate inertia' or the time it will take for ice and the atmosphere to respond to the 390>PPM CO2 now measured by the NOAA in HI. I read Dr. Hansen's book- he speaks of this inertia- regarding ice melting- it a slow process, but once it starts there is little chance for stopping it. And this melting is going to accelerate at around 400ppm CO2. The OP talks about the urgency we now face- with C02 at such high levels as today- and rising rapidly. Have we passed into the zone of 'Dangerous climate change'- Hansen feels we have- can we stop 'extremely dangerous climate change?' Just my OP- we are in deep deep trouble- and the world seems totally aloof.Moderator Response: [Daniel Bailey] Salient points, all.For those paying attention, the demise of Multi-Year (MY) Arctic Sea Ice currently ongoing (expect to see seasonal open water at the pole by 2012 at summer melt maximum, this summer if weather conditions are more conducive). With the albedo-flip kicking in, the energy poured into killing off millennia-old MY ice will then go into the warming of the Arctic Ocean itself, with the result of longer and longer melt seasons each year & a corresponding ramp-up of ice loss from both the Greenland Ice Sheet and the West Antarctic Ice Sheet. More Polar Amplification to come (in the pipeline).
Is the pot in the red danger zone if the steam is blowing the lid off the pot?
Not that the world is fiddling while Rome is burning; more like just Wubbling down (since I missed the good doctor's birthday last week).
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DebfromTN at 23:28 PM on 8 March 2011Climate Emergency: Time to Slam on the Brakes
In response to the prior comments about how politicians need persuasion to pay attention to the scientific data and take action now, I would like to request permission to share this link all over the place, i.e. C-Span. There is a discussion there now inviting comments about whether or not President Obama should open our oil reserves in a hope to reduce the prices at the pump. I would like to share this link there. As you know, I do not have a scientific educational background to be able to offer any intelligent discussion to this link, but I do have common sense and it tells me I should pay attention to the scientific data and open my mind to the discussions among the experts. I know Mother Earth is pretty resiliant, but what I take away from this article, is that even she has her limits and her sustainability for human existence will turn on us eventually if we don't start changing now. Convincing the consumers consumed with consumption will be the tricky part.Moderator Response: [Daniel Bailey] Welcome to Skeptical Science! Feel free to link to any article posted here.To get the most out of this educational site, we recommend that Newcomers, Start Here and then learn The Big Picture. I also recommend watching this video on why CO2 is the biggest climate control knob in Earth's history.
Further general questions can usually be be answered by first using the Search function in the upper left of every Skeptical Science page to see if there is already a post on it; odds are, there is. If you still have questions, use the Search function located in the upper left of every page here at Skeptical Science and post your question on the most pertinent thread.
Remember to frame your question in compliance with the Comments Policy and lastly, to use the Preview function below the comment box to ensure that any html tags you're using work properly. Thanks for taking the time to post your comment!
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Arkadiusz Semczyszak at 23:14 PM on 8 March 2011Climate Emergency: Time to Slam on the Brakes
@ranyl “... that some models suggest that the CO2 that gone into the sinks will be released and there is of course the climate warming CO2 feedback with gives out about 10-20ppm per 1C.” Ensemble reconstruction constraints on the global carbon cycle sensitivity to climate, Frank et al., 2010.: “But themagnitudeof theclimate sensitivityof theglobal carboncycle (termed c), and thus of its positive feedback strength, is under debate, giving rise to large uncertainties in global warming projections.” “Our results are incompatibly lower (P,0.05) than recent pre-industrial empirical estimates of 40 p.p.m.v. CO2 per 6C (refs 6, 7), and correspondingly suggest 80% less [!!!] potential amplification of ongoing global warming.” -
Arkadiusz Semczyszak at 22:36 PM on 8 March 2011Interactive animation of the climate change impact on agriculture
Sorry, The beginning of my post should be something like the following: @Chris G “... increased warmth in Russia lead to higher yields last year.” This comment is ... -
Arkadiusz Semczyszak at 22:34 PM on 8 March 2011Interactive animation of the climate change impact on agriculture
This comment is ... But first, arguments - later opinion. Once again, the drought in Eastern and Central Europe is linked to the sharp change in ENSO from LN to LN - rapid drop (June - July) in temperature of the oceans (typical for the past two decades). This phenomenon causes changes in atmospheric circulation - effects ? - such as droughts in China. Just as in 2003 and 2006 - violent La Nina (need not be a big change - as the 2007 / 8, but it must be quick - rapid change) = drought in many areas of NH. Warming = warm winters. 1. I am eng. agro-meteorologist. 2. Generally, both the higher concentration of CO2 and temperatures favor most crops. It is textbook knowledge. Any cause of climate change in some areas of decline in the growth of other cereal production. The most visible example of this in Africa. “Projected impacts relative to current production levels range from −100% to +168% in econometric, from −84% to +62% in process-based, and from −57% to +30% in statistical assessments.” (Climate change risks for African agriculture, Müller et al., 2011.) Model Mann & Babb is too simple, would be real ... -
MarkR at 21:31 PM on 8 March 2011Climate Emergency: Time to Slam on the Brakes
"I wonder if SkS should switch entirely to how we move public opinion and therefore the politicians? The scientific case is iron-clad (despite the protestations of a few posters)." I completely disagree with that... Very few sites provide SkS' level of analysis with such accessibility. IMO SkS is about using the scientific method to cut through the rubbish. That's been done very well for the physical science: SkS has clearly pointed out that it's not the Sun causing global warming, but on the other hand that 7 metres of sea level rise isn't going to happen tomorrow. In terms of actions, it's a lot harder. But taking the approach of explaining the effects of different policies based on peer reviewed work so that those with a political bent can make informed decisions is where SkS should be IMO. That's what James' article here is about: explaining the evidence behind claims of climate sensitivity and why this should be factored into any risk analysis for the future. -
johnd at 21:29 PM on 8 March 2011Interactive animation of the climate change impact on agriculture
The Ville at 21:08 PM, the claimed low rate of correlation of growth versus CO2 is very much reminiscent of trying to find trees whose tree-ring measurements reflected temperature driven growth. What percentage of trees in what percentage of sites worldwide have been able to provide suitable trees? Would it be that the same problem affects those trees as that which Briffa found with his trees and his divergence problem. -
ranyl at 21:25 PM on 8 March 2011Climate Emergency: Time to Slam on the Brakes
Not sure that paleoclimatic records support CS is 3C...they seem to point to it being somewhat higher! "Together, it is clear that during the Cretaceous and Paleogene climate sensitivity commonly exceeded 3°C per CO2 doubling." "Fossil soils constrain ancient climate sensitivity" Dana L. Royer1, PNAS | January 12, 2010 | vol. 107 | no. 2 | 517–518, Birgit Schneider and ralph Schneider "Global warmth with little extra co2" nature geoscience | VOL 3 | JANUARY 2010 |pg 6, "The conclusion of a high Earth system sensitivity5,13 is particularly worrying if there is a potential for the hitherto slow components of the climate system to respond more quickly in the face of rapidly increasing CO2 emissions." In this paper the CS long term (1000yr say) with all natural variation taken into account is ~8-12C, "If changes in carbon dioxide and associated feedbacks were the primary agents forcing climate over these timescales, and estimates of global temperatures are correct, then our results imply a very high Earth-system climate sensitivity for the middle (3.3 Myr) to early (4.2 Myr) Pliocene ranging between 7:1 +/- 1:0C and 8:7 +/-1:3 C per CO2 doubling, and 9:6=+/-1:4 C per CO2 doubling, respectively." "High Earth-system climate sensitivity determined from Pliocene carbon dioxide concentrations" Mark Pagani1*,NATURE GEOSCIENCE j VOL 3 j JANUARY 2010 "The surface in our PE control simulation is on average 297K warm and ice-free, despite a moderate atmospheric CO2 concentration of 560 ppm. Compared to a pre-industrial reference simulation (PR), low latitudes are 5 to 8K warmer, while high latitudes are up to 40K warmer." Warm Paleocene/Eocene climate as simulated in ECHAM5/MPI-OM M. Heinemann, Clim. Past, 5, 785–802, 2009 On average the PE was 9.4C hotter with large polar amplification and a CO2 basically double, so that makes CS 9.4C. It must be remembered that 1000yr CS from Paleo data is higher than the 100CS used in models, the 100CS is about 60% of the 1000yr. So for the long term 9.4C that is 5.64C and so on, "If the temperature reconstructions are correct, then feedbacks and/or forcings other than atmospheric CO2 caused a major portion of the PETM warming." "Carbon dioxide forcing alone insufficient to explain Palaeocene–Eocene Thermal Maximum warming" Richard E. Zeebe1, Nat. Geo. PUBLISHED ONLINE: 13 JULY 2009 | DOI: 10.1038/NGEO578 In this one the CS is about 9-12C again, but as in the quote the authors feel the CO2 CS is a definitive and thus say another factor is necessary rather than CS being higher. There are plenty more of these and the recent article in science again suggesting CS is underestimated and the article last year by Gavin Schmidt saying it was 30-40% down. It does seem to make no sense to me that the CS is going to a standard figure all the time, as it is dependent on multiple none-linear feedbacks the size of which varies depending on the initial conditions. How can Earth with no ice albedo feedback have the same CS to GHG as one with loads of ice? One with no permafrost have the same CS as one with ,lots melting? At present we have a polar ocean melting, and lots of permafrost to melt. It also clear form this paper that temeprature changes can be dramatic and tipping point in nature, ("Another look at climate sensitivity" I. Zaliapin1 and M. Ghil2,3 Nonlinear Processes in Geophysics), so trying to get a statistical CS from paleodata isn't going to easy as the CS is dependent on initial conditions, and many studies suggest it is higher than thought or modelled, it is more likely that the PDF of CS should be a range humps and bumps ranging long twerm from 6-12C. Which hump the world is currently at is hard ot say, but with polar sea ice to go and permaforst etc, it is likely to be on the high side of things probably. "The conclusion from this analysis—resting on data for CO2 levels, paleotemperatures, and radiative transfer knowledge—is that Earth’s sensitivity to CO2 radiative forcing may be much greater than that obtained from climate models ( 12– 14)." "Lessons from Earth’s Past " Jeffrey Kiehl;14 JANUARY 2011 VO 158 L 331 SCIENCE SO yeah things are urgent very very urgent, for a CS as high as suggested from the past means 350ppm gives a 95% probability spread of temperautre rise by 2100 of 1.8-3C. Now how are we going to get 40ppm of CO2 out of the atmopshere, especially considerign that some models suggest that the CO2 that gone into the sinks will be released and there is of course the climate warming CO2 feedback with gives out about 10-20ppm per 1C. How high can CO2 go before the accumulation of heating is too much for 2C not be a definitive, 400ppm peak, even that seems risky buisness considering. Of course the present CO2 is 390ppm, so to peak at 400ppm would mean only adding another 5 year or less carbon into the atmosphere, divide that up fairly arround the world and it means the west has 1 year of emissions to play with for a carbon budget, so not much and considering all the adaptation that will be needed not much at all. Does anyone think that this is in anyway doable? If bold plans like ZeroCarbonBritain by 2030, cause peak CO2 of 434ppm and that isn't counting all the extra carbon needed to replace everything (cars with electric cars, power infra-structure, all white goods for efficient ones, changing the face of farming etc). And also remember the biosphere basically are only hope of drawing CO2 down (carbon cpature is a ruse to keep using fossil fuels and there isn't enough energy in the world to run special CO2 exchange machines and where do we put the carbondioxide for it seems to leaking from the all sites it has been burioed at so far!!). Is a fossil fuel free society even possible anymore? For that would take changing the whole economic system as the current system has to grow and the only way for that to occur is by using fossil fuels. The only way to get CO2 out the atmosphere quickly is to stop putting in quickly and the only way to do that is stop using power. -
Paul D at 21:08 PM on 8 March 2011Interactive animation of the climate change impact on agriculture
Camburn: "Each study I have read concerning co2 and plants results in a higher level of co2 being benifical for plant growth." Then your reading is biased. Read wider. Do trees grow to infinity by continually adding CO2? http://www.uoguelph.ca/news/2010/10/forests_arent_t.html "Studying archived tree-ring measurements held by the National Oceanic and Atmospheric Administration in the United States, they found CO2 fertilization spurred faster tree growth at only about 20 per cent of sites worldwide, despite the fact that the gas typically accelerates growth in plants." -
Paul D at 21:04 PM on 8 March 2011Interactive animation of the climate change impact on agriculture
adrian smits: "As a farmer I know that you need heat units to grow crops and the corn belt in north America has been moving north for years.We consider this a blessing that allows us to grow crops with higher yield and it gives us a greater choice as to what we can grow." God bless America and screw everyone else! What sort of choices are there in deserts? As I said, humanity needs biodiversity, just as much as corn and wheat. -
johnd at 20:32 PM on 8 March 2011Interactive animation of the climate change impact on agriculture
muoncounter at 15:53 PM, the objective of the study you introduced, can first be deduced from this second sentence in Longs introduction,- "The CO2 fertilization factors used in models to project future yields were derived from enclosure studies conducted approximately 20 years ago." note the word models. This is then elaborated on in the paragraph headed- "How have CO2 fertilization factors been derived?" Which begins with "Most models used to predict future crop yields, including those within the IPCC (5), are from two families: ............" The final paragraph notes- "The FACE experiments clearly show that much lower CO2 fertilization factors should be used in model projections of future yields;....." It seems patently clear to me that the "food for thought" is really all about the adequacy or otherwise of the models being used as benchmarks. -
iana at 20:17 PM on 8 March 2011Climate Emergency: Time to Slam on the Brakes
@15 Probabilistic Forecast for 21st Century Climate Based on Uncertainties in Emissions (without Policy) and Climate Parameters maybe read first then comment -
iana at 20:11 PM on 8 March 2011Climate Emergency: Time to Slam on the Brakes
@14 CO2 lags temperature - what does it mean? -
Gilles at 20:11 PM on 8 March 2011Climate Emergency: Time to Slam on the Brakes
another remark :" CO2 is rising by 2 ppm per year as we continue to burn fossil fuels.... Under business as usual, we are heading for up to 1,000 ppm by 2100" of course a simple computation shows that 1,000 ppm by 2100 requires an average +15 ppm/yr, more than 7 times the current rate. Obviously this is only possible with an exponential growth throughout the century - exponential growth is a very useful tool to predict a lot of catastrophe since it requires only a small number of doubling times to reach any reasonable threshold. The basic question is however : how long is an exponential growth sustainable ? -
Gilles at 19:42 PM on 8 March 2011Climate Emergency: Time to Slam on the Brakes
Rob, Bern, thanks, but I still don't understand the answer : why did temperature decrease so much although CO2 remained constant during several centuries? what was the driver then ? -
Bern at 18:51 PM on 8 March 2011Climate Emergency: Time to Slam on the Brakes
Gilles @ 10: that's what climate models are for, to take into account the many disparate factors that affect climate. And there are a lot more than just two factors in this particular feedback system... In any event, the lead/lag of CO2 w.r.t. Temperature is dealt with by this SKS page. I highly suggest you read the intermediate version, and discuss it there. -
Rob Painting at 18:49 PM on 8 March 2011Climate Emergency: Time to Slam on the Brakes
Gilles @ 10- Q. maybe you could explain why temperatures often decrease BEFORE CO2 (e.g., -280 000 , -215000, -130000) A. Woolly mammoths and saber-toothed tigers didn't drive SUV's. -
Bern at 18:47 PM on 8 March 2011Climate Emergency: Time to Slam on the Brakes
Actually, Bob, while that may be the fastest response, a better approach would be: "Persuade Republicans (and other conservative groups) that climate change is real & needs to be addressed." Of course, that's likely to be a *lot* harder, particularly with the disinformation being promulgated by special interest groups who are opposed to climate action on (mostly) financial grounds. It's like farriers & stable owners lobbying to have motorcars banned on 'safety' grounds, except in this situation they're getting awfully close to succeeding... (especially as the benefits of climate action are a lot harder to see than the benefits of motor vehicle use!) alan_marshall: don't forget the polar amplification effect - a 10ºC warming at the poles may be much less on a global scale. Having said that, Hansen argues that the interglacial peaks in the proxy records are constrained by non-temperature factors, so the actual temperature may have been higher. He also argues that we might see 5 metre sea level rises by the end of the century, with another 20 metres over the next few centuries. (see here for details) So, yeah, the long-term challenge is great. It's certainly been acknowledge by the climate science side of the debate. The other side has just barely acknowledged that it's even warming... -
Gilles at 18:33 PM on 8 March 2011Climate Emergency: Time to Slam on the Brakes
Alan : If I have misinterpreted this graph, will someone please explain it to me? maybe you could explain why temperatures often decrease BEFORE CO2 (e.g., -280 000 , -215000, -130000) , after the spike ? and also explain how you can disentangle the sensitivity of temperature with respect to CO2, and the sensitivity of CO2 with respect to temperature (there are TWO factors in a feedback system)Moderator Response: This is discussed in the thread "CO2 lags temperature". - James -
Bob Guercio at 18:23 PM on 8 March 2011Climate Emergency: Time to Slam on the Brakes
actually thoughtfull at 16:24 PM on 8 March, 2011 said: "I wonder if SkS should switch entirely to how we move public opinion and therefore the politicians? The scientific case is iron-clad (despite the protestations of a few posters). We need to figure out how to move people, politicians and nations towards action." Bob Guercio's response: "Vote Democratic in the United States" -
alan_marshall at 18:09 PM on 8 March 2011Climate Emergency: Time to Slam on the Brakes
Hansen's findings confirm my worst fears. I have long been concerned that the medium-term models are understating long-term climate sensitivity.
Have a fresh look at the familiar Vostok ice core data above, which plots the results through four ice ages and five interglacial periods. Notice that both CO2 and temperature spike at the start of the interglacial periods. The pattern is consistent. An increase in CO2 from 180 to 280 ppm is associated with a rise in temperature at the poles of more than 10°C. The increase in CO2 is less than double, yet the increase in temperature is greater than projected for doubled CO2 in medium-term models. I see this as evidence the estimates for climate sensitivity derived from such models are likely to be conservative.
If I have misinterpreted this graph, will someone please explain it to me? If I have correctly interpreted it, the long-term challenge is greater than has so far been acknowledged.
Moderator Response: [DB] Fixed html issue. -
Gilles at 18:05 PM on 8 March 2011A Real-World Example of Carbon Pricing Benefits Outweighing Costs
dana : Gilles #72 - "Oil is needed for transportation, heating" No it's not. Transportation can be accomplished with electric vehicles to a large degree, and there are alternatives to heating with oil." Dana, I'm speaking of current facts. Oil IS NOT used for electrical power in developed countries, so the "alternatives" you mentioned are simply not relevant to replace it. Oil IS used for 98 % of transportation. You may imagine that electric cars could replace it, but they don't develop even if the barrel hit 150 $ - instead, we have recessions that make simply more people poorer - which doesn't help them to buy expensive electrical cars of course (BTW , the electricity is mainly made from fossil fuels in the world, so even electric cars wouldn't change the CO2 production). I'm just living in a real world. " "mainly because climate is hotter, maybe ?" No, because California has implemented energy efficiency technologies. Our per capita energy consumption has barely increased over the past 30 years. The rest of the country's has increased significantly." I don't know the figure for all US states; I'm just noticing the "barely increased" ... " "without carbon, there is nothing but the poorest life you can imagine." First of all, nobody is saying we're going to eliminate all carbon, and secondly, claiming that we can't have a high tech lifestyle without massive carbon emissions is utterly absurd." I am saying that we're going to eliminate all fossil carbon, just because it is a finite resource, and before being exhausted, it will first decrease significantly. And there is nowhere and never a "high tech lifestyle without massive carbon emissions" : stating that it is "utterly absurd" to predict something that happens everywhere and in all times is ... surprising. There are much more facts that show the dependance of modern life on fossil fuels than on average temperature. Actually , ALL facts show that our way of life is totally dependent on FF consumption, and NO fact shows that it depends strongly on average temperature. -
Gilles at 17:53 PM on 8 March 2011Climate Emergency: Time to Slam on the Brakes
sorry a part of sentence is missing. (dC/dT)c is the variation of fossil fuel consumption necessary to get a climate change per unit T. -
Gilles at 17:51 PM on 8 March 2011Climate Emergency: Time to Slam on the Brakes
always the same strange assumptions, that the life of mankind is very sensitive to the temperature, but very insensitive to the fossil fuel consumption, whereas all objective data and facts show exactly the opposite. Try a simple exercise. Adopt a "wealth indicator" X (it can be GDP but also any fancy indicator you want). By comparing different countries, compute the "sensitivities" dX /dT and dX/dC where T is the local average temperature and C the fossil fuel consumption. Then to compare dimensionnally comparable constants, compute dX/dT and dX/dC. (dC/dT)c where the latter factor is the variation of fossil fuel consumption. Give me the result, and conclude.
Moderator Response:Climate change isn’t only about temperature. With global warming comes
• Ice sheet collapse and sea level rise, as discussed in my article.
• An intensification of the water cycle which paradoxically means both more intense rainfall and more droughts.
• Expansion of the drought-ridden subtropics.
• Glacier melt, which will cause water shortages for hundreds of millions of people.
• Amplifying feedbacks which cause more warming.
• Also, the unusually rapid rate of global warming we are causing will make it very difficult for ecosystems – not to mention humans – to adapt.
• In addition to global warming, fossil fuel burning is causing ocean acidification faster than it occurred in the Paleocene-Eocene Thermal Maximum.
• I could go on.
And of course wealth is correlated with fossil fuel consumption, because that’s currently where we get most of our energy from. The whole point is we need to change that. - James
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Bern at 17:37 PM on 8 March 2011Climate Emergency: Time to Slam on the Brakes
rpauli: Going cold turkey on fossil fuel is nice in theory, but in practice? Economic disaster, is how I'd describe it. Which is really sad, because it's really what needs to be done. The next best thing is the "gradual phase out", which can be achieved by simply saying "no more coal-fired plants may be built or refurbished". That's a big call on it's own, but it'd certainly put the wind up the power generators to develop alternate sources of energy. Of course, in nations like Australia, where the word "nuclear" is immediately associated with "Chernobyl" in the minds of many, the options are limited somewhat. I really hope some of the promising alternate generation techniques get off the ground *fast*. There seems to be great reluctance, however, for investors to back anything other than nice, safe, predictable coal. As per my comments on the Climate Show thread, I think we're going to have to build a lot of rather large, solar and/or nuclear powered CO2 capture plants, to try to reduce atmospheric concentrations faster than natural processes will do so. That truly would be a "World War II" scale effort, but instead of building tanks & planes & bombs, those factories would be producing sequesterable carbon. This may become a requirement for the survival of human civilisation if, for example, we see significant amounts of clathrate or permafrost methane leaking out as the earth continues to warm. Even if we don't see that methane release, we'd still need to take out "extra" CO2, as the oceans would release plenty more as atmospheric concentration dropped. Herculean effort? I'll say... (Somewhat depressing, aint it?) -
r.pauli at 17:11 PM on 8 March 2011Climate Emergency: Time to Slam on the Brakes
Great posting. The " 1) phase out coal by 2030." - is carbon capitulation. Way too late; too much delay. That gives in to economic interests that caused this problem. Coal combustion should be stopped now. Instead, suggest an ASAP/PDQ approach such that ANY carbon energy is used only for the purpose of establishing clean, renewable energy systems. Starting now. No other use of coal energy shall be permitted.Moderator Response: Obviously that's not feasible - we will need power during the transition. But yes, I agree coal combustion should be stopped ASAP. - James -
mjp at 17:01 PM on 8 March 2011Climate Emergency: Time to Slam on the Brakes
galloping camel i've reviewed a lot of those "others" interpretations in following an interest in this for around 7 years some are simply wrong some are cleverly deceitful others are narrow answers to the wrong question so open your mind your touching faith in the 1% or so that deny the large majority of the scientists isn't touching it's downright dangerous and naieve -
gallopingcamel at 16:49 PM on 8 March 2011Climate Emergency: Time to Slam on the Brakes
You have touching faith in James Hansen who manages to draw "amazing" conclusions from data that others interpret quite differently. -
actually thoughtful at 16:24 PM on 8 March 2011Climate Emergency: Time to Slam on the Brakes
I wonder if SkS should switch entirely to how we move public opinion and therefore the politicians? The scientific case is iron-clad (despite the protestations of a few posters). We need to figure out how to move people, politicians and nations towards action. -
muoncounter at 15:53 PM on 8 March 2011Interactive animation of the climate change impact on agriculture
johnd, Here's how Long describes the source of what you're dismissing as 'models': ... most information about crop responses to elevated CO2 is obtained from studies in greenhouses, laboratory controlled-environment chambers, and transparent field chambers, where released CO2 may be retained and easily controlled. He then compares these artificial hot-house conditions (which are actual results, not models) to long-term real-world outdoor trials. Which result do you think will better match farm experience - for people who don't grow their crops under glass? -
muoncounter at 15:42 PM on 8 March 2011Interactive animation of the climate change impact on agriculture
From Ainsworth 2008 reports on findings with the all-important rice crop (which is not grown in greenhouse gas-enriched closed environments): The rise in atmospheric [CO2] will be accompanied by increases in tropospheric O3 and temperature. When compared with rice grown in charcoal-filtered air, rice exposed to 62 ppb O3 showed a 14% decrease in yield. Many determinants of yield, including photosynthesis, biomass, leaf area index, grain number and grain mass, were reduced by elevated [O3]. While there have been too few studies of the interaction of CO2 and O3 for meta-analysis, the interaction of temperature and CO2 has been studied more widely. Elevated temperature treatments negated any enhancement in rice yield at elevated CO2 ... -
johnd at 15:40 PM on 8 March 2011Interactive animation of the climate change impact on agriculture
muoncounter at 14:28 PM, you are putting the wrong emphasis on the results. The lower yield claim is comparing the FACE trials to those expected by modeling which was based on enclosure trials. It is basically supporting this which I had posted earlier- "Numerous free air carbon enrichment field trials are providing some such data, IIRC, the existing models generally failing to reliably forecast the increased yields many such trials produce." The FACE trials all showed positive responses to the CO2 enrichment for all 3 parameters across all 3 grains. The failure is with the modeling assumptions. Those who actually read the paper will see as much indicated near the end. One of the objectives of the FACE trials was to provide real data that would allow the models to be calibrated rather than just using assumptions. I don't think you'll find the big difference between the greenhouse and the real world, that is fairly well understood by those in the industry. As you have shown, the big difference is between the assumptions being made in the modeler's office and the real world. -
Citizen99 at 15:38 PM on 8 March 2011Human CO2 is a tiny % of CO2 emissions
mikea01 - it is also inaccurate to consider the discussion in these posts as some kind of convocation of "experts" and thus judge that there is little agreement among them. In fact, my perception is that this site tends to be flooded with ramblings from inexpert ideologically motivated denialists whose purpose is to create the exact impression of non-agreement that you are reporting. In fact, it is established beyond doubt that more than 95% of real "experts" (i.e., folks who know what they are talking about) do agree that climate change resulting from the massive combustion of fossilized hydrocarbons is becoming a serious threat to our fragile modern civilization. Please take the time to read one of the excellent books on the subject written by actual experts such as Dr. James Hansen. -
johnd at 15:11 PM on 8 March 2011Interactive animation of the climate change impact on agriculture
adrian smits at 14:18 PM, I agree also. Within agriculture, as with most fields, there is a huge pool of knowledge that has been accumulated along the way. Much of it is considered self evident amongst those who carry it. In many cases, techniques are developed without any formal scientific input, the scientists often left to produce a paper trail long after the practice had become standard procedure. -
actually thoughtful at 14:52 PM on 8 March 2011A Real-World Example of Carbon Pricing Benefits Outweighing Costs
I am not sure we need to divert 100 billion into researching this new, 24/7 non solar, non fossil, non wind, non nuclear answer. If I could control all government spending, sure I would lower spending on say, fossil fuel subsidies or war and increase on long shot total replacements. But the answers are already here. We have a long, long, long way to run before we've begun to utilize solar, wind and wave to meet our needs, as CAmburn points out, nuclear has a role. Why wouldn't every available penny be dedicated to the tested, here-and-now solutions? That is what you would do if you thought it was a critical problem. So I don't think your point hangs together as you dismiss the technologies that are already working (solar, solar for heat, wind, wave, nuclear, etc) in the search for this new holy grail. { - snip - }Moderator Response: [DB] The referenced comment was deleted. -
muoncounter at 14:28 PM on 8 March 2011Interactive animation of the climate change impact on agriculture
adrian s, "adding c02 to greenhouse air is standard practice" Ironic: Greenhouse gases are good for plants in greenhouses. But we're not necessarily talking about plants in greenhouses here. Here's one of those peer-reviewed thingies everybody talks about. Long et al 2008: Free-air concentration enrichment (FACE) technology has now facilitated large-scale trials of the major grain crops at elevated [CO2] under fully open-air field conditions. In those trials, elevated [CO2] enhanced yield by ~50% less than in enclosure studies. This casts serious doubt on projections that rising [CO2] will fully offset losses due to climate change. Apparently there's a big difference between conditions inside the greenhouse and the outside world. -
johnd at 14:26 PM on 8 March 2011Interactive animation of the climate change impact on agriculture
With at least two contributors to this thread known to be real world farmers, this allows some balance to be bought to the subject which is otherwise only about theoretical models based on a few assumptions, some perhaps not even the most relevant. Theories and formulas founded on laboratory experiments ultimately have to be validated against the knowledge accumulated by such real world farmers who operate in a infinitely more variable environment than any lab can recreate. That knowledge is very often supported by reliable data going back generations covering a wide range of variable conditions in an otherwise constant environment, one that is generally very well measured for all the relevant parameters required. As has already been pointed out, there are many more important variables that have to be taken into account, if not for the projections being made, then certainly to allow the models to be calibrated against past data. Numerous free air carbon enrichment field trials are providing some such data, IIRC, the existing models generally failing to reliably forecast the increased yields many such trials produce. Most of the debate about climate change revolve around statistics, theories and formulas, and peer reviewed papers. But there is a real place in the debate for those people, those with dirt under their fingernails, who are in the unique position to be able see whether the way the climate performs in theory is how it actually manifests itself on the ground. Talking of ground, whilst agriculture depends on conditions that exist at ground level and below, virtually none of the measurements, such as temperatures, CO2 are taken from inside the growing zone. With temperatures, especially the extremes, there is generally a great difference between what is measured 1.2m above the surface and what it actually is right in the growing zone. This in understood by the scientists who work in agriculture, but I don't see anywhere where climate scientists use this different set of data.Moderator Response: For some scientific studies of the effects of CO2 and heat, see the summary by the U.S. Dept. of Agriculture, and other studies, linked in the comments of the thread "CO2 is not a pollutant." -
adrian smits at 14:18 PM on 8 March 2011Interactive animation of the climate change impact on agriculture
Camburn is right Michael I have read similar articles.In fact adding c02 to greenhouse air is standard practice because it increases yields dramatically. -
Camburn at 14:14 PM on 8 March 2011Interactive animation of the climate change impact on agriculture
I will state this and then have to head to bed: Each study I have read concerning co2 and plants results in a higher level of co2 being benifical for plant growth. It appears that plants must have evolved during a time when co2 levels were substantially higher than present. Their growth response to co2 is almost like a growth response to nirtrogen/phosphorous etc. People who grow food in greenhouses have known this for years and elevate the level of co2 to compensate. It is not yet practical on a commercial farm scale to do so. If it was, it would have been done.
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