Roy Spencer's paper on climate sensitivity
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Spencer's model is too simple, excluding important factors like ocean dynamics and treats cloud feedbacks as forcings. |
Climate Myth...
Roy Spencer finds negative feedback
"NASA satellite data from the years 2000 through 2011 show the Earth's atmosphere is allowing far more heat to be released into space than alarmist computer models have predicted, reports a new study in the peer-reviewed science journal Remote Sensing. The study indicates far less future global warming will occur than United Nations computer models have predicted, and supports prior studies indicating increases in atmospheric carbon dioxide trap far less heat than alarmists have claimed." (James Taylor)
Climate scientists have identified a number of fundamental problems in Spencer and Braswell's 2011 study which wrongly concludes that the climate is not sensitive to human greenhouse gas emissions. One of the main problems with the paper is that it uses Roy Spencer's very simple climate model which we've previously looked at in .
This simple model does not have a realistic representation of the Earth's oceans, which are a key factor in the planet's climate, and it also doesn't model the Earth's water cycle. One key aspect in the Earth's temperature changes is the El Niño Southern Oscillation (ENSO), which is a cycle of the Pacific Ocean. Spencer's model does not include ENSO, and he assumes that ENSO responds to changes in cloud cover, when in reality it's the other way around.
There are some other key problems in the paper. It doesn't provide enough information for other scientists to repeat the study. When two other climate scientists (Kevin Trenberth and John Fasullo) tried to replicate its results as best they could with the information provided, they found quite different results (see the Advanced version of this rebuttal for further details). Spencer and Braswell's conclusions also only seems to work using the satellite data set they chose, but Trenberth and Fasullo found that using other data sets also changes their results.
Trenberth and Fasullo also found that when using a few different climate models, the one which replicated the observed data best was the one with a climate more sensitive to greenhouse gases, which directly contradicts Spencer and Braswell's conclusion that the climate is not sensitive to greenhouse gases.
It's also worth noting that the journal which published Spencer and Braswell's paper does not normally publish climate science research. This may explain how the paper made it through their peer-review system with so many problems. In the end, Trenberth and Fasullo find that the Spencer and Braswell study has no merit.
- The model it uses is far too simple to accurately represent the Earth's climate
- The paper doesn't provide enough information to replicate their results
- Their results depend on using one particular data set
- They assume that ENSO responds to cloud cover changes, when in reality, the reverse is true
- The study's conclusions are incorrect and unsupportable
UPDATE 3 Sep 2011: Wolfgang Wagner, has stepped down as editor-in-chief of the journal Remote Sensing. Wagner concluded the Spencer's paper was "fundamentally flawed and therefore wrongly accepted by the journal". More here...
Last updated on 1 August 2011 by dana1981.
Deon, I have responded to your assertion #1 on the post that is the counterargument to the myth "Models are Unreliable." If you want to comment further on that topic, do so on that thread, not this one. That topic is off-topic for this thread you are reading now.
Deon wrote:
Deon, climatologists are well aware of Milankovitch cycles. Indeed, there is an excellent post here on Skeptical Science about them. For more details including math, see Tamino's "Wobbles, Part 1," then "Wobbles, Part 2." Then Tamino's "Milankovitch Cycles" that mentions that currently and for the past really long time Milankovitch Cycles have been cooling, not warming, the Earth. For that last point, details are in the Hansen and Sato paper "Paleoclimate Implications for Human-Made Climate Change." If you want to discuss orbital cycles more, do so on the Skeptical Science post "Milankovitch Cycles," not on this thread. Off-topic comments on this thread will be deleted.
Deon wrote:
See "CO2 Lags Temperature--What Does It Mean?" Put comments on that topic on that thread, not this one. Off-topic comments on this thread will be deleted.
Deon wrote:
See "It's a 1,500 Year Cycle." Put comments on that topic on that thread, not this one.
Deon wrote:
See "It's Not Us." And comment there, not here.
I don't have time to answer Deon's #4 and #5 right now. If nobody else has done so after a few hours, I will.
Deon wrote:
Deon, the "human activity" that is the most important cause of anthropogenic global warming and the attendant other climate changes is increase in greenhouse gas emissions into the atmosphere and to a lesser degree reduction of natural greenhouse gas removal from the atmosphere. I am flabbergasted that you lack such fundamental knowledge yet are strident in your criticisms of the science, and implicitly, the scientists. You really need to stop criticizing until you've learned the basics. Start here at Skeptical Science with The Big Picture. Then to learn how that knowledge was built, read The History of Climate Science. Because you seem untrusting, you should then follow up by reading more details of the history in Spencer Weart's The Discovery of Global Warming. After all that, if you have some specific questions please post them here on Skeptical Science but on the appropriate thread.
Deon wrote:
Deon, there is a huge amount of data from a huge number of sources collected by a huge number of people over a huge number of years. Your criteria that you are presenting as absolute of course have not been met, but they are not met in any scientific field--not any. Period. Obviously you are not a working scientist in any field, because your misunderstanding of science is profound.
Deon wrote:
Deon, the natural forcings have been teased out from the human forcings. One place to see a summary of that evidence is the Advanced tabbed pane in the post "It's Not Us." Just one example of detail is that the Sun's input to Earth has been stable (or even decreasing slightly) since at least 1960.
Please do ask questions here at Skeptical Science. But do so on the appropriate threads. If you're unable to find an appropriate thread despite making a sincere attempt to use the list of Arguments and the Search field (which is at the top left of every page), then comment on the most recent Weekly News Roundup.
Tom Dayton, I want to aplaud your excelent series of responses to Deon. In particular I liked your response regarding the theory/observation split in science (which many people do not understand). Deon, read carefully and learn.