BPSDB Double the CO2 – Half the literacy – 1/10th the coherence
‘Doubled CO2 means just 1.64 degrees of warming…’ or maybe not.
Potholer54 is back with another good one, this time debunking the “not much warming for two centuries” nonsense. Potholer pretty much covers it all, so I’ll leave it to him.
Half the literacy
Even before the Lewis Page version of this meme turned up Deniers were using a report on the NASA Press Release that had been posted at WUWT and echoed around the Denialosphere as the basis for claiming that climate change was not a problem.
They weren’t speaking with the same kind of certainty about details that Page gave them, but they were confident that “plants slow Global Warming” was somehow synonymous with “all but completely stopped.”
Watts actually did include the relevant quote “… it is not a strong enough response to alter the global warming trend that is expected“, and even put that high up in the article, which was duely copy/pasted by many in the Denial echochamber, so it’s not that the fact wasn’t out there. Even so, obviously most Deniers either couldn’t grasp what that meant, and/or they don’t even read Denier posts for more than the headlines (I suspect both).
So Page has certainly added a higher level of false precision to a bogus story, but the Deniers were already running with it as yet another fable. Thankfully this video debunks either version, so that’s handy.
1/10th the coherence
Just for giggles, go to any site that posted the Lewis Page story and do an internet site search of that site for these other denier fables:
i) “global cooling” OR “Global warming ended”.
Find the stories that claim we are cooling, not warming like this one. Ask why they post a story about dampening “the warming” if they believe the Earth is cooling. Why do stories about something that is not happening?
ii) “CO2”
Find the stories that claim CO2 is not a greenhouse gas (GHG), or a minor one compared to water vapour etc like this one., or that CO2 climate sensitivity is low. Ask why, if they believe CO2 is not an important GHG, does it matter if plants absorb a little more of it.
iii) “Climate Models”
Find the stories about how climate computer models don’t work & are useless (eg like this one). Ask them why we should believe this new study which is based on a computer model if computer models of climate are useless.
I am sure you get the idea, so also try
iv) “NASA” & “corrupt” for stories like this one
v) “corrupt” and “climate scientists” for stories like this one.
You’ll find that Climate Change Denier has no problem believing that:
“The warming that isn’t happening will be slowed by plants absorbing more of a gas that doesn’t (really) affect climate at all. I know this is true because I was told by scientists I don’t trust from an agency that lies about science who did a study using tools that don’t work.”
Did I miss any there? Does this story contradict other Denier claims (as so many of their beliefs do).
A real question
A question that I have about the model which I am hoping someone can answer concerns the assumptions about precipitation. From the abstract:
“When we combine these interactions in climate simulations with 2 × CO2, the associated increase in precipitation contributes primarily to increase evapotranspiration” [Emphasis added]
Under climate change precipitation changes are not going to be uniform, with many arid areas getting more arid, and wet areas getting more so. Stressed plants will use less CO2 and even release methane (eg here, here and here) as a response to stress, thus acting as a positive feedback. eg
- Corralling The Carbon Cycle: Calculating How Much Carbon Dioxide Is Absorbed And Released By Plants
- Importance of carbon dioxide physiological
forcing to future climate change - Stressed Plants Could Negatively Influence the Climate
- Plants and Climate Change: It’s Not That Simple
To what extent did the model incorporate this non-uniform response? If the model assumes a homgeneous increased precipitation, then the negative feedback is grossly overestimated.
I find it hard to believe that the authors might have missed something that obvious, but I’d still feel better if it was stated explicitly rather than assuming it. Does anyone know?
We give our consent every moment that we do not resist.
IMAGE CREDITS:
Global map of terrestrial net primary production From ‘Global Carbon Project‘
Sources and sinks induced by the production and metabolisation of food products. From ‘Global Carbon Project‘
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[…] […]
There’s a recent report of a model projection showing that polar bear populations may be at less risk if emissions are curbed. http://www.theaustralian.com.au/news/health-science/polar-bears-could-be-saved-by-slower-melt-nature-report/story-e6frg8y6-1225971977975 This is what one denier blockhead wrote about the study:
“”The risk of polar bears becoming extinct may have been overestimated” is exactly the conclusion a reasonable man would draw from the evidence being presented. Of course this does not mention the far stroner empirical evidence that polar bear numbers are actually increasing. What the authors have done is to try to provide themselves with a get out clause when the polar bear refuses to become extinct..its a common strategy in AGW literature these days, rather than admit the models are completely and utterly wrong, come out with a tweak to the parameters to try to pretend that the theory fits the observations. ”
So in the first sentence he claims that the model provides compelling evidence and in the third claims that they are completely and utterly wrong.
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Hi,
Good example. Yes, the same research that shows that the changes in the Arctic are currently very rapid and include dramatic loss of summer ice/dramatic loss of habitat, and is consistent with empirical observations of the rapidly declining polar bear populations in the southern areas of their Arctic range, is offering a faint hope of possibly avoiding complete loss if we can make dramatic and immediate reductions in emissions. That is what the study says. But as your example shows, Mr. Denier prefers instead to make up his own conclusion rather than going with the researchers’. That’s because he’s the smartest. 😉
Many people (but not Mr. Denier) are already aware that many experts consider the ice-free scenario most likely. The lead author of this study also considers the ice-free scenario most likely, but he is demanding intervention because 1) we haven’t reached the point where the summer sea ice is already completely gone, yet, and 2) there are things we can do that we are not doing (non-agreements in Cancun and Copenhagen don’t help).
[…] […]
780ppm CO2 is NOT what scientists mean by a doubling of CO2.
Doubling from preindustrial levels of 280 to 560. The 780 ppm number is something made up by deniers to confuse the issue. Yes that would be a doubling from present level of almost 390 ppm, but that isn’t what is normally meant by “doubling of CO2”
This is what deniers typically do, misrepresent the science and what the IPCC and climate scientists have actually said.
from a response by moderator, to a comment at Skeptical Science
comment Response: “Actually, the past gives us a good insight into where we’re headed into the future. Our lower CO2 emission scenarios have global temperatures rising by around 2°C. The last time our climate was this warm, around 125,000 years ago, global sea levels were over 6 metres higher than today. So we are on a current trajectory for sea level rise of at least 6 metres. There is some uncertainty about how quickly this might happen – at the moment, the peer-review research indicates we’ll face 1 to 2 metres sea level rise by 2100 but how quickly we reach 6 metres is uncertain.”
Yeah, no big deal. Most climate scientists think doubling CO2 will cause overall warming, counting feedbacks, of close to 3 C.
“Our lower CO2 emission scenarios have global temperatures rising by around 2°C.”
I think the key words here are “lower CO2 emission scenarios”
“as climate science has developed and advanced over time , estimates have converged around 3°C. ” ……………..
As the scientists at RealClimate put it,
‘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, calling 2°C a danger limit seems to us pretty cavalier’.”
http://www.skepticalscience.com/detailed-look-at-climate-sensitivity.html
“Scientists have been surprised by the rapid warming of the Arctic, where annual temperatures have increased two to three times faster than the global average. In one part of the Arctic, over the Barents and Karas Seas north of Scandinavia, average annual temperatures are now 10 degrees C higher than they were in 1990.”
“It has been one million years, some think 14 million years, since the Arctic was ice-free,” Barber told….”
“European Union warns: Mediterranean Sea region could see an increase of 7 degrees Celsius”
“On Monday the Guardian reported that climate change scientists warn of a 4 degrees Celsius global temperature rise by 2060, that is to say within our lifetime. Of course 4 degrees Celsius is a global average. Europe now warns that the situation could be even worse in the Mediterranean Sea region. A temperature increase of 7 degrees Celsius is predicted before the end of the century.”
http://www.greenfudge.org/2010/12/02/european-union-warns-mediterranean-sea-region-could-see-an-increase-of-7-degrees-celsius-this-century-due-to-climate-change/
Recommend: University of Washington’s Polar Science Center chart of Arctic Sea Ice Volume.
http://psc.apl.washington.edu/ArcticSeaiceVolume/IceVolume.php
But, not to worry.
Just keep your head in the sand and you won’t even notice.
Sailrick.
What the deniers often do is leave out positive and negative feedbacks (despite often claiming water vapour is a more important GHG). Hence you get lower figures for climate sensitivity when feedbacks are ignored (the deniers) and higher figures when they are included (the science).
If you only calculated temperature rise based only on the radiative forcing of CO2, you would get low numbers (which is what deniers like), it’s the feedback processes that vary the results based on where your base date for starting the calculations is.
Doubling CO2 can mean a lot of things because it is relative. More importantly no matter where you start your calculations it is the feedback mechanisms that determine bigger or smaller results than would be the case with just CO2 radiative forcing.
Well, they use a (Colorado State) GCM that includes vegetative effects, so I think people can presume that much of the global and regional effects are included.
The biggest caveat to this paper seems to be the assumption that vegetation distribution is fixed. This is a big IF considering the possibilities of wildfires, foresting, etc. Levis et al. (2000) combines the two effects (vegetation cover and canopy conductance) and shows that they both have impact. Cao et al. (2010) may be a good counterpoint to this study although it doesn’t include effects of down-regulation (note: me not an expert).
I’m more interested in why the Colorado State GCM only produces a 2K increase for doubled CO2 (w/ a higher baseline nonetheless). People are comparing the sensitivity of the vegetative effects w/ vs. w/o down-regulation, but the difference between the +2-4.5K “consensus” and the +2K is more significant.