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Dr. Jay Cadbury, phd. at 06:35 AM on 19 April 2011David Evans' Understanding of the Climate Goes Cold
"The assumption is simply that the Arctic Ocean as a whole is warming at the average of the stations around it. What people forget is that if you don't put any values in for the areas where stations are sparse, then when you go to calculate the global mean, you’re actually assuming that the Arctic is warming at the same rate as the global mean. So, either way you are making an assumption." Albatross I understand his point about having to put in values for where stations are sparse but I would be more at peace if they added more surface stations. And this is what is frustating to me, at the last congressional hearing, Lindzen was arguing with the scientists on the other side about the surface station measurements and the issue went unresolved. -
More Carbon Dioxide is not necessarily good for plants.
A rhetorical question: Why do some people think that cherry-picking quotes and numbers from the middle of presentations and papers, while ignoring the summary and conclusions sections that provide the take-home message for all the data, is in any way an acceptable tactic? -
Alec Cowan at 06:28 AM on 19 April 2011The e-mail 'scandal' travesty in misquoting Trenberth on
@Ken #136 Quit spamming, Ken! You simply cannot find K&D saying their own figures are for any deeper than 0-700m. If you could, you simply have showed it and pointed a finger at me. The fact that you didn't but you still have time for playing ping-pong here is self explanatory. -
More Carbon Dioxide is not necessarily good for plants.
johnd - My apologies; I had looked at the second reference you made in this post, defending BP, not your earlier post the day before. From that PowerPoint on Australian FACE experiments (only), Slide 14: "Increases and Decreases in Yield BUT Despite experimental yield increases, due to future predicted changes in rainfall and increases in temperature: - Semi-arid zone: Yield LOSS (-10 to -20%) in North West Victoria - HRZ: Yield GAINS (+10 to +20%) in the South West" (Capitalization as in original) Looks like a wash to me - any CO2 based increases nullified by resulting temperature and hydrology shifts. You are not making your case. -
dhogaza at 06:23 AM on 19 April 2011More Carbon Dioxide is not necessarily good for plants.
"As to redneck commercial growers and new seed varieties - great" Reminds me of the Chicago Cubs fan who, every fall, says "just wait until next year!" -
Rob Honeycutt at 06:10 AM on 19 April 2011David Evans' Understanding of the Climate Goes Cold
Jay @ 29... Regarding the satellite data and the surface station not matching, I wonder if you're pulling up old data somehow. Or maybe someone else you're reading is referring to old data. For quite a while there was a discrepancy between the satellite data and the surface station data. There was a big rift where no one was understanding why the two methods were returning different results. This went on for quite a while. Then an outside group was reviewing the UAH satellite data and discovered that they (Spencer and Christy at UAH) were not accounting for orbital decay of the satellite. That decay introduced a cooling trend (or less of a warming trend) into the UAH data. Spencer and Christy finally had to admit that their data was in error and correct it. Once they did their data matched the surface station data sets almost perfectly. -
More Carbon Dioxide is not necessarily good for plants.
johnd - "KR at 04:35 AM, you obviously missed the results of the FACE trials I referred to in johnd at 19:31 PM on 18 April, 2011" Actually, I did look at the second article you linked. From their conclusions: "Overwhelmingly, this has shown that data from laboratory and chamber experiments systematically overestimate the yields of the major food crops, yet may underestimate the biomass production of trees." More wood, but less food? Again - the FACE experiments you have pushed, with more realistic testing then lab/greenhouse work, do not show the crop amplification you have suggested will occur. As to redneck commercial growers and new seed varieties - great, let us know when they have something. In the meantime, the data indicate that CO2 is not going to boost crops the way skeptics have claimed. -
Alec Cowan at 06:00 AM on 19 April 2011More Carbon Dioxide is not necessarily good for plants.
@Berényi Péter #103 Speaking of real science and given that you speak of every branch of science as if you know it. Can you explain how those FACE experiments could keep the CO2 enrichment in wind conditions, which accounts for a great deal of water strain? Also, can you comment the fact that the vegetation studied is mainly for human use, directly or indirectly, that is, varieties have been enhanced to maximize growth and productivity and to resist drough by every possible way, thus they might "be expecting" more CO2? Why don't we humans enrich our environment with 28% Oxygen just to feel good? Why don't we add some 30% food to our diets, just to thrive? (Oh, we do! and the only thing that thrives is our spare tyres -those in the middle and with a navel in front-)
The fact is that the brochure is a very poor one and unfortunately some very serious works are misinterpreted or depicted in a wrong fashion. There are also not so serious works, but all of that is outside the importance of that brochure to the present topic. On the practical side, the image equals you simply saying "raising CO2 has made soils and vegetation richer in Carbon during the last +100 years". How do we know? Just because if you have had a better source you would have used it, and that, sir or madam, that almost equals a confession.
About your snippets -the sort of figures and phrases that you are recently laying in any imaginable nest- you selected the image on the right from a brochure that also contains the image at the bottom.
At this time you should know better and get some graphic with margin errors in it, proper attribution and a dataset. Also checking the source, a very poor one -no matter who did it- no matter it is just a brochure. In the image below they only speak of drought. No single place becomes any wetter and even a new dessert is born in southern Chile ... wait! the scale is wrong: 40% doesn't mean 40% less rainfalls, just a 40% probability of the place going dryer, hence a 60% probability of it going wetter. How do I know? Because it's what Mahli et al (2008) says, and that's why a source is needed. I can also tell that the season name is the NH's though most of the area represented is in the SH.
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Albatross at 05:49 AM on 19 April 2011David Evans' Understanding of the Climate Goes Cold
Interesting, Jay, you do realize that the GOP want to slash NOAA's budget, right? And now we have contrarians arguing that the station dropout is an issue. Anyways, the station dropout has been demonstrated to be a non issue by the CCC. This is not big nor is it recent news. Please, instead of obfuscating, your credibility would be much better served by actually calling Evans on the myriad of errors in his speech/essay. Why are "skeptics" so unskeptical of their own, and so reticent to critique their own or call them on their errors? Mind you I should not complain, it is for this very reason that "skeptics" will probably always have a huge credibility issue. PS: Re the station issue, please read this (see last question). -
Dikran Marsupial at 05:39 AM on 19 April 2011David Evans' Understanding of the Climate Goes Cold
It is also worth noting that the various surface station products measure slightly different things (e.g. coverage of poles), which are again slightly different from what the satellite products measure (surface rather than lower trophosphere), so you wouldn't expect them to be exactly the same anyway. -
LukeW at 05:33 AM on 19 April 2011More Carbon Dioxide is not necessarily good for plants.
Albatross - be careful interpreting the increased variability. Land clearing in reef catchments has increased runoff which is what the coral proxy study is based on. And land clearing itself can accentuate droughts when they occur. Villabolo - you really are trying to stop the tides - yes I am Australian and your basic knowledge of our climate history isn't very good. (1) don't build homes and infrastructure on flood plains - lessons of 1974 forgotten to be rediscovered in 2011 (as the lessons from the 1800s were also forgotten). Is it that surprising that flood plains ... errr ... flood ! It is absolutely stunning that Australians are surprised by the floods. (2) any Aussie crop physiologists and modellers worth their salt knows that episodic droughts and floods make production problematic. We live on the receiving end of ENSO - you HAVE and WILL get episodic droughts and floods. And any ecologist knows the big wets are the resets for decades of low rainfall years. If you don't like it - don't live here. Are you trying to suggest none of this has happened before. In fact probably historically much worse in the 1800s. Those who don't learn from history are doomed to repeat it. And the ENSO x IPO story is written large in the rainfall history, sediment cores and corals. Not enjoying such variation Aussies mitigate against drought and flood using a thing called "dams". How many billion dollars do you think full dams and rivers are to agriculture? -
Albatross at 05:33 AM on 19 April 2011David Evans' Understanding of the Climate Goes Cold
Jay @27, Your questions have been answered in the main post. The long-term trends in the satellite data and surface data are in good agreement, especially the between the RSS products (which are superior to the UAH data that the contrarians are so focussed on) and the surface temperature data. Why don't you look at the data yourself (trends for 1980-2010) at woodfortrees.org? Tamino also has a good post on this issue, well worth the read. Either way, Evans was completely wrong to state that the "official" science do not track the satellite data. I'm sure that we can agree that Evans was demonstrably wrong on that point. And be wary of uncritically citing "information" from political lobby groups like the SPPI-- recall Monckton is with them too, and he has been debunked more times than I care to recall. -
Dr. Jay Cadbury, phd. at 05:31 AM on 19 April 2011David Evans' Understanding of the Climate Goes Cold
Here is a pull quote from the article that concerns me. "The world’s surface observing network had reached its golden era in the 1960s-1980s, with more than 6000 stations providing valuable climate information. Now, there are fewer than 1500." This concerns me because 1500 stations does not seem adequate enough to measure the entire system. Secondly, what range are these stations accurate up to? -
Dr. Jay Cadbury, phd. at 05:28 AM on 19 April 2011David Evans' Understanding of the Climate Goes Cold
He sent me a pdf, which you can download here. http://scienceandpublicpolicy.org/originals/policy_driven_deception.html -
les at 05:21 AM on 19 April 2011More Carbon Dioxide is not necessarily good for plants.
128 Johnd "modeled projections are... at best only theories based on opinions." No. Some are based on well understood models and data while other are not so good. BPs assertion that the famous clipped diagram shows an exponential rise was clearly a theory based on opinion which the data in the FACT paper didn't uphold. Personally, I think he did a great job of correcting himself and supporting the blog post. -
Dr. Jay Cadbury, phd. at 05:18 AM on 19 April 2011David Evans' Understanding of the Climate Goes Cold
@Chris Extremely interesting and informative post. Evans: "Why does official science track only the surface thermometer results and not mention the satellite results?" "This would be a good question, if it were remotely true. In reality, "official science" pays very close attention to satellite temperatures. For example, they're discussed in great detail in the IPCC report and highlighted every single month by NOAA." I am confused here because I have read some scientists who say that the surface and satellite data does not match. "The satellite data shows little long term warming. Ground station data shows a lot of warming. The ground-station data has serious systematic problems with the urban heat island effect and station dropout over the years. I put much more faith in the satellite data. “Satellite data” normally means the temperature of the lower troposphere, not the surface temperature. Have a look at the attachment."-Dr. Happer I will post his attachment shortly, as I am waiting for it to finish downloading. -
johnd at 05:08 AM on 19 April 2011More Carbon Dioxide is not necessarily good for plants.
KR at 04:35 AM, you obviously missed the results of the FACE trials I referred to in johnd at 19:31 PM on 18 April, 2011. The science isn't settled just yet, plant genetics is moving at a fast pace. The irony is that some red necked croppers involved in commercial seed trials is going to know where the science is at years before you get to read about it in some peer reviewed study available free online. -
villabolo at 04:52 AM on 19 April 2011More Carbon Dioxide is not necessarily good for plants.
#133 Volunteer: "Increased carbon dioxide in the air actually decreases the amount of water needed by plants, because most water lost by plants is lost by transpiration. When plants can access carbon dioxide more efficiently, they "breathe" less and emit less water vapor." I and others have already responded to that issue. If you do not believe that are responses are accurate, by all means, tell us why. To return to the original statement, however, is to communicate with the rest of us as if we never responded. Please pick up your discussion of the issue from where it was last left. There is no need to reinvent the wheel. "In response to the questioning of the "clipped" chart -- obviously the author cut it off where he did because everything past that point was a projection, not a measurement. Proponents of global warming are learning that projections can't be trusted." Volunteer; it is totally irrelevant that BP cut out a section that he believed did not apply to his point. That is grossly unprofessional. If he does not believe in its relevancy or accuracy, the proper thing to do is to post the entire image and then to explain why he believes that particular portion of it is not relevant. To do as he did is to represent the evidence in a way that the originator of the did not intend. It also causes those who look at the chart to have faith in the assumption that nothing has been taken out of context; intentionally or not. Finally, your quote marks on the word clipped is disingenuous. -
Rovinpiper at 04:36 AM on 19 April 2011Earth hasn't warmed as much as expected
Daniel Bailey@11 That is exactly what I was looking for. Thanks. -
villabolo at 04:35 AM on 19 April 2011More Carbon Dioxide is not necessarily good for plants.
@125 Albatross: Thank you, Albatross. It would be nice if this thread changed topic to other aspects of my post like the one you mentioned. I can see that posters here are beginning to repeat issues that have already been answered in detail. One good example is #133. -
More Carbon Dioxide is not necessarily good for plants.
johnd - I agree, "As always it is what happens and observed in the real world that counts." Why is it, then, that you continue to push the idea of greatly increased crop yields with CO2 increases, when FACE trials indicate that those optimistic projections are not correct? -
Albatross at 04:34 AM on 19 April 2011More Carbon Dioxide is not necessarily good for plants.
Wow, some people are just not reading this thread and literature being cited properly (Volunteer I am looking at you). The doctored figure. Can you imagine the fuss the "skeptics" would make if say, the decline was removed from a certain dendrochronology. Oh wait, we have been there, and they are still screaming about that one even though in that case they were valid reasons for ding so. But I digress, BP was hiding the decline. Someone ought to tell the self-procliamed auditors at a certain blog ;) -
muoncounter at 04:27 AM on 19 April 2011More Carbon Dioxide is not necessarily good for plants.
Volunteer#133: "projections can't be trusted." They sure can't; things are worse than they were projected to be. See the new thread Do the observations match the models? -
Volunteer at 04:23 AM on 19 April 2011More Carbon Dioxide is not necessarily good for plants.
Increased carbon dioxide in the air actually decreases the amount of water needed by plants, because most water lost by plants is lost by transpiration. When plants can access carbon dioxide more efficiently, they "breathe" less and emit less water vapor. In response to the questioning of the "clipped" chart -- obviously the author cut it off where he did because everything past that point was a projection, not a measurement. Proponents of global warming are learning that projections can't be trusted. -
johnd at 04:22 AM on 19 April 2011More Carbon Dioxide is not necessarily good for plants.
KR at 04:09 AM, the FACE experiments are useful in that they identify which modeling based on laboratory enclosure experiments is wrong or totally useless, something that needs to be kept in mind for all modeling perhaps. As always it is what happens and observed in the real world that counts. -
Albatross at 04:15 AM on 19 April 2011More Carbon Dioxide is not necessarily good for plants.
JohnD @128, Yes, BP did grab those section titles from the paper-- but he did not provide full context and did not draw people's attention to the other key (negative) findings made by the authors. It is unfortunate that that BP and now you intent on not being true to the primary conclusions of the paper. They are optimistic only if they can figure out why the plants are not responding favourably to elevated CO2 levels-- maybe b/c they have not had time to adapt to those levels to take advantage...who knows...they don't seem to know. I could be wrong, but I think that you would be hard pressed o find a lead author on the paper who thinks that continuing wit BAU is acceptable in view of the evidence. Again, not all the lessons point to a negative outcome (that is also stated in the IPCC), at least when viewed individually, but this paragraph from the paper under discussion should be cause for concern for those who are prudent and risk averse: "More broadly, the stimulation of seed yield in response to growth in elevated [CO2] is ∼50% lower in FACE experiments than in enclosure studies for the world's four most important crops (Long et al., 2006; Ainsworth, 2008; Ainsworth et al., 2008a)." Now let us look at some of Dr. Leakey's earlier work: SP Long, EA Ainsworth, ADB Leakey, J Nosberger & DR Ort (2006) Food for thought: Lower than expected crop yield stimulation with rising carbon dioxide concentrations. Science 312:1918-1921 ADB Leakey, M Uribelarrea, EA Ainsworth, SL Naidu, A Rogers, DR Ort & SP Long (2006) Photosynthesis, productivity and yield of Zea mays are not affected by open-air elevation of CO2 concentration in the absence of drought. Plant Physiology 140:779-790 Again, the prudent path here is to prepare for the worst rathe than wishful thinking that we can overcome the problems identified in the FACE experiments. And that means reducing GHG emissions. Sorry, but BP has scored quite the own goal, and your post is not helping him. It is not clear to me that the FACE experiments considered heat stress. I found no specific reference to the impact of heat stress in the body text. -
More Carbon Dioxide is not necessarily good for plants.
johnd - I completely agree, it's well worth reading the literature. Reading this particular paper, I was struck by statements such as: "A comparison of wheat yields from five different crop models with FACE results showed that the mean response ratio to elevated [CO2] was overestimated by more than a factor of two in the model projections .... Thus model parameterization and validation with summary data from FACE and non-FACE studies show that the quantitative differences in how crops respond to CO2 in the field compared to in chambers has important consequences for global food supply projections. Equally FACE has revealed factors operating in the open field situation that were not or cannot be identified by chamber experiments, for example, increased herbivory and performance of herbivore populations .... Most important though will be understanding why our major food crops fail to achieve the improved production under elevated [CO2] that can be achieved in protected environments and by some non-crop species." Emphasis added, references (in original) snipped for space issues and because I didn't want to copy their bibliography. FACE experiments are very useful - sadly, what they are revealing is that the skeptical predictions of greatly increased crop yields do not hold up under real conditions of CO2 increase, let alone accompanying heat stress and hydrology changes that will be factors as well. -
Alexandre at 04:01 AM on 19 April 2011Christy Crock #4: Do the observations match the models?
This suggests the IPCC is consistently biased towards a conservative projection, leading to observable consistent errors. I think that's enough reason to rethink this policy. -
Bob Lacatena at 03:54 AM on 19 April 2011More Carbon Dioxide is not necessarily good for plants.
125, Albatross, So according to BP, one study growing two species of trees in glass domes shows that trees are going to love the new CO2 age. On the other hand, a huge swath of the Amazon is dying right before our eyes. Gee. I wonder what I should believe.Moderator Response: (DB) Perhaps wise investors should place their money in glass dome manufacturing plants. -
johnd at 03:41 AM on 19 April 2011More Carbon Dioxide is not necessarily good for plants.
I think it needs to be pointed out that the paper Berényi Péter at 21:23 PM was commenting on, Journal of Experimental Botany (2009) 60 (10): 2859-2876. doi: 10.1093/jxb/erp096 is one of the papers Chris S at 19:54 PM recommended as a must-read paper about the FACE experiments, Journal of Experimental Botany http://jxb.oxfordjournals.org/content/early/2009/04/28/jxb.erp096.full Apparently apart from myself and BP few others have bothered to read any of those recommended, otherwise they would know that the points made by BP were taken directly from the paper referred to including point 6, which he specifically commented on. Point 6 also confirms a point I made earlier, as well as often previously, about how FACE trials are the only means by which modeling based on laboratory enclosure experiments are able to be assessed for the first time in real world open air field conditions. It seems that in most cases, as already elaborated on, the modeling generally fails to predict the actual outcomes, and thus, before they, the models, can be relied on to provide any useful predictions as to what might happen under future real world conditions, they need to be able to first accurately predict the outcomes of FACE trials. Indeed, this is one of the main purposes of the FACE trials, but many casual observers seem ignorant of this aspect. I think this should also be kept in mind whenever modeled projections are discussed, until they are confirmed by observations in the real world, they are at best only theories based on opinions. Overall the paper supports arguments generally made by many sceptics, but it first needs to be read throughly by those capable of absorbing and understanding the contents, or at least holding some small knowledge of the subject under discussion, but therein lies the problem. -
Albatross at 03:37 AM on 19 April 2011Christy Crock #4: Do the observations match the models?
Thanks Dikran :) -
Philippe Chantreau at 03:35 AM on 19 April 2011More Carbon Dioxide is not necessarily good for plants.
BP: "a bit less" Author: "much lower" Good idea to look at that paper, indeed. -
muoncounter at 03:30 AM on 19 April 2011More Carbon Dioxide is not necessarily good for plants.
Albatross#125: "Talk about a positive feedback!" Here's another: Texas Co-ops Threatened by Wildfires. In an interesting ironic twist, the governor who wants to do away with environmental protection and has threatened to secede now is crying for federal protection: A Major Disaster Declaration makes the state eligible for response and recovery assistance from the federal government. -
Composer99 at 03:27 AM on 19 April 2011Christy Crock #4: Do the observations match the models?
Gilles: As shown in the graph, the Arctic ice remains within the bounds of aggregate model run hindcasts/forecasts for Arctic sea ice extent until dropping below the average bounds in the first decade of the 21st century (although I can see it remains within the bounds of some of the model runs even then). As such, your claim to the contrary in #1 appears to be plainly false. What is your point? ===== Incidentally, the Arctic sea ice extent graph (Figure 2) would be a good addition to the Climate Graphics resource; assuming RealClimate allows it. -
muoncounter at 03:19 AM on 19 April 2011Christy Crock #3: Internal Variability
GIlles#111: "It "just" changes the influence of forcings" Explain please. In specific terms, with specific forcings, in the context of this thread: over periods of a few decades, modeled internal variability does not cause surface temperatures to change by more than 0.3°C, and over longer periods, such as the entire 20th Century, its transient warming and cooling influences tend to average out "I already answered that precisely ... models converge towards an absence of drift " This should go to the 'models are unreliable' thread, where you will find your 'answer' makes little sense. But your position has descended into the circular: If models didn't converge, you'd be screaming they are unreliable; if they do converge, you claim that's what they are designed to do. Life must be good when you get to argue both sides. -
Albatross at 03:14 AM on 19 April 2011Christy Crock #4: Do the observations match the models?
Dikran @5, Could you please specify which papers are you referring to?Moderator Response: [Dikran Marsupial] I have updated my post, it now includes links to the publishers website and to .pdf files (no paywall) -
Dikran Marsupial at 03:12 AM on 19 April 2011Christy Crock #4: Do the observations match the models?
Christy is still citing a paper he co-authored with Douglass (www, pdf) as proof that the models don't match the observations of tropical trophopshperic temperatures, but doesn't mention that that paper was comprehensively refuted by a paper By Ben Santer and 16 other authors (www, pdf). The statistcal test used in the Douglass paper was obviously incorrect, and showed a complete lack of understanding of climate modelling. That the test was inappropriate is clearly demonstrated by the fact that a model with perfect physics, infinite temporal and spatial resolution and an infinite number of model runs (to perfectly capture the statistical properties of internal climate variability) is guaranteed to fail the test, even thought it is perfect. The test used in Santer et al. is rather better (if still too conservative). -
Albatross at 03:08 AM on 19 April 2011Christy Crock #4: Do the observations match the models?
Dikran @3, "Can I suggest we ignore Gilles until he comes up with something a bit more substantive?" Agreed and seconded. To stay on topic. I find it intriguing how the "skeptics" are unsketpical of model findings should they happen to support their position (e.g., spencer's model), but otherwise they are deemed to be useless. As you may know, Lindzen is also guilty of Christy's mistake and deception on this file. -
Dikran Marsupial at 02:56 AM on 19 April 2011Christy Crock #4: Do the observations match the models?
Gilles@1 GEP Box said "all models are wrong; but some models are useful". We all know the models are not going to get every prediction exactly right, it is unreasonable to expect them to do so. Nothing you have written suggests they are not usefull; if anything it suggests they under-estimate the possible threat. Can I suggest we ignore Gilles until he comes up with something a bit more substantive? -
Albatross at 02:54 AM on 19 April 2011Christy Crock #4: Do the observations match the models?
James, Nice post. So yes, Christy deceived, again. And Christy also ignored the fact that the models are being too conservative on some important fronts. Just a couple of notes on that RC figure. The grey zone is the 95% confidence interval so +/- 2 standard deviations which is a very wide margin, the observed temperatures would probably almost exclusively fall within a +/- one std deviation envelope. Also the observed rate of warming compares very well with the projections, from RC, my notes in square brackets: For the GISTEMP and HadCRUT3, the trends are 0.19+/-0.05 [0.14-0.24] and 0.18+/-0.04ºC/dec[ade], [for the 1984-2010 period]. For reference, the trends in the AR4 models for the same period have a range 0.21+/-0.16 ºC/dec (95%). -
Gilles at 02:36 AM on 19 April 2011Christy Crock #4: Do the observations match the models?
so to summarize * temperatures are "well within a range" .. so large that there would be very difficult to imagine how they couldn't (0.8 °C width with an average of 0.15°C/decade ! ) * sea level rise is just at the border * arctic ice is out of range of simulations .. that were already out since 1960 (obviously the trend didn't match the simulations even at the time when they were done ! ) * stratosphere has cooled... but not quite exactly as you should expect is the cooling was due to the blocking of LWR from below - which is supposed to increase regularly with time. Instead you seem to have abrupt changes after major volcanic eruptions (El Chichon and Pinatubo). Any idea why ? -
Albatross at 02:35 AM on 19 April 2011More Carbon Dioxide is not necessarily good for plants.
Well, according to the 'skeptics', because we have increased CO2 by 40% above pre-industrial levels drought should no longer be much of an issue at all. But this is what is really happening on the ground during extreme drought:
[Source]
"Analyses of rainfall across 5.3 million square kilometres of Amazonia during the 2010 dry season, published tomorrow in Science, shows that the drought was more widespread and severe than in 2005. The UK-Brazilian team also calculate that the carbon impact of the 2010 drought may eventually exceed the 5 billion tonnes of CO2 released following the 2005 event, as severe droughts kill rainforest trees. For context, the United States emitted 5.4 billion tonnes of CO2 from fossil fuel use in 2009."
Talk about a positive feedback! And more "cheering" news:
"The authors suggest that if extreme droughts like these become more frequent, the days of the Amazon rainforest acting as a natural buffer to man-made carbon emissions may be numbered."
A PDF of Xu et al. (2011) can be found here.
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Albatross at 02:17 AM on 19 April 2011More Carbon Dioxide is not necessarily good for plants.
BP @103, "Let's see some real science." What a truly bizarre statement to make, especially after what you have done earlier on this thread. And since when is "your" science "real" science? I'll give the paper a read......good gracious I did not even have to get past the abstract. BP, please tell us why you chose to leave out this lesson from your list (which was so important that they included it in the abstract)? "Finally, the stimulation of yield by elevated CO2 in crop species is much smaller than expected." Oh and this, from the same paper: "Most important though will be understanding why our major food crops fail to achieve the improved production under elevated [CO2] that can be achieved in protected environments and by some non-crop species." There is some hope though: "Overcoming this could deliver a 10–15% increase in crop yields by 2050, an increase that could be critical with an anticipated 3 billion increase in global population coupled with climatic change adverse to crop production. " Yet from their final paragraph: "Overwhelmingly, this has shown that data from laboratory and chamber experiments systematically overestimate the yields of the major food crops, yet may underestimate the biomass production of trees." The authors clearly fail to see the hearty optimism of the 'skeptics'. -
villabolo at 02:13 AM on 19 April 2011More Carbon Dioxide is not necessarily good for plants.
@111 CBDunkerson: David Horton wrote: "Anyone else get the feeling we are just wasting our time answering this kind of stuff?" I try to keep mental note of the people who have proven themselves completely beyond reason and ignore them. Granted, that leaves whatever nonsense they post 'un-rebutted', but any such can always be addressed later should anyone suggest that it could have validity. In echoing that sentiment let me emphasize that we have to address ourselves to the general public with the idea in mind that a "Skeptic' will be looking over their shoulders and spouting off his nonsense. That means that we don't really need to emphasize technical arguments/rebuttals but instead simplify the issues in order to "innoculate" the public. -
villabolo at 02:04 AM on 19 April 2011More Carbon Dioxide is not necessarily good for plants.
@107 David Horton: "I am tired of that game." We need to play another game. -
Rob Honeycutt at 02:02 AM on 19 April 2011More Carbon Dioxide is not necessarily good for plants.
DM @ 119... Totally agreed. You might say that BP "Moncked it up." -
Albatross at 01:58 AM on 19 April 2011More Carbon Dioxide is not necessarily good for plants.
I would like to highlight a couple of things for readers, Arkadiusz made a post @83, trying to convince us that higher temperature will not be bad for the tropical forests. Two readers who took the trouble to dig a little deeper into the paper find that the results are not relevant to the current and future situation-- 200 years versus 10 000-20 000 time span. Now what does the skeptic do? Does he acknowledge this and cede the point? No, he ignores the critique and simply posts another paper @92. And nice try BP @97, but please do not insult our intelligence. You have been told repeatedly that this is not so much about where we have been or are but where we are headed if we continue under BAU. Your fraudulent graph was misleading and ignored the fact that its assessment agrees with the topic of the post-- moderate CO2 increases (and warming) favour an increase in biomass, but if CO2 goes way up, then vegetation does not fare well. Too much of a a good thing may very well be a bad thing. Try consuming a cup or two of salt to find out. Luke @100, Yes, you were speculating, thanks for confirming. I do not need links on how ENSO and IPO affect rainfall thanks, that is not what is at issue here so much as you claiming that we are headed for a period of more frequent La Ninas. That may or may not be true, but unless backed up by some science, it remans simple speculation. With that said, you seem to be basing your projection on the work of Verdon and Franks (2006). At least one of the papers that you cited has not helped you case: "Although there appears to be no overall trend toward wetter or drier conditions [over Queensland], the reconstructions suggest that the variability of rainfall and river flow has increased during the twentieth century with more very wet and very dry extremes than in earlier centuries, as projected for the region as a consequence of global warming." An increase of rainfall variability is not conducive for better crop growing conditions. And their work validates the IPCC projections. And I should have not have to point this out, but flooding (as was associated with this past La Nina) is clearly not conducive for agriculture either. Too much water is also a bad thing for crops and and other vegetation. -
Dikran Marsupial at 01:53 AM on 19 April 2011More Carbon Dioxide is not necessarily good for plants.
Rob Honeycutt@116 For me the issue is that BP was using a graphic from a source that contradicts his position without mentioning that fact. It is a bit like taking a quote from a paper out of context to support an argument, where the paper as a whole supported an opposing position. Using a graphic or a quote from a report implicitly suggests that the report provides some support for your position. Somehow I don't think it would have passed without comment if say James Hansen had used a cropped picture from a climate skeptic report that was cropped in such a way as to ignore the central message of the report. -
Gilles at 01:46 AM on 19 April 2011Christy Crock #3: Internal Variability
and an example of publication (but I'm sure there are others and you know it very well) http://www.esrl.noaa.gov/psd/people/gilbert.p.compo/CompoSardeshmukh2007a.pdf " Several recent studies suggest that the observed SST variability may be misrepresented in the coupled models used in preparing the IPCC's Fourth Assessment Report, with substantial errors on interannual and decadal scales (e.g., Shukla et al. 2006, DelSole, 2006; Newman 2007; Newman et al. 2008). There is a hint of an underestimation of simulated decadal SST variability even in the published IPCC Report (Hegerl et al. 2007, FAQ9.2 Figure 1). Given these and other misrepresentations of natural oceanic variability on decadal scales (e.g., Zhang and McPhaden 2006), a role for natural causes of at least some of the recent oceanic warming should not be ruled out. Regardless of whether or not the rapid recent oceanic warming has occurred largely from anthropogenic or natural influences, our study highlights its importance in accounting for the recent observed continental warming. Perhaps the most important conclusion to be drawn from our analysis is that the recent acceleration of global warming may not be occurring in quite the manner one might have imagined. The indirect and substantial role of the oceans in causing the recent continental warming emphasizes the need to generate reliable projections of ocean temperature changes over the next century, in order to generate more reliable projections of not just the global mean temperature and precipitation changes (Barsugli et al. 2006), but also regional climate changes." No need to say that if even the decadal variability may be "misrepresented", this can only be worse at the century timescale. -
Rob Honeycutt at 01:42 AM on 19 April 2011More Carbon Dioxide is not necessarily good for plants.
David Horton @ 107... Yes, it's worth going through this over and over and over (IMHO). I always say this: It's not about changing anyone's mind who is posting here. We will never change Gilles, BP, or any other of the minds that are already made up. But in responding to their claims and debating their positions we have the opportunity to change the minds of others who come to SkS to read about this issue. Think of it as a public debate with a large audience. When you post here you are up on the stage making a point. You don't need to convince the person at the other podium whom you're responding to. You need to convince the audience. I would contend that the audience is always changing too. Even though we might have the same discussions here repeatedly with the cast of characters, there are more and more people reading SkS all the time. New minds ready to learn more about climate science. One of the great things about this site is the heavy moderation. When I go read WUWT it's more like you walked into a clubhouse where everyone thinks alike and is slapping each other on the back, and attacking anyone who doesn't think like they do. Here at SkS there is a more hearty, genuine debate.
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