http://dotearth.blogs.nytimes.com/2011/08/08/on-arctic-sea-ice-and-warmth-past-and-future/"But even as I push for an energy quest that limits climate risk, I’m not worried about the resilience of Arctic ecosystems and not worried about the system tipping into an irreversibly slushy state on time scales relevant to today’s policy debates. This is one reason I don’t go for descriptions of the system being in a “death spiral.”
The main source of my Arctic comfort level — besides what I learned while camped with scientists on the North Pole sea ice — is the growing body of work on past variability of conditions in the Arctic. The latest evidence of substantial past ice variability comes in a study in the current issue of Science. The paper, combining evidence of driftwood accumulation and beach formation in northern Greenland with evidence of past sea-ice extent in parts of Canada, concludes that Arctic sea ice appears to have retreated far more in some spans since the end of the last ice age than it has in recent years.
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Michael MacCracken, a veteran climate modeler and chief scientist at the Climate Institute, noted on the Google group on geo-engineering that this new paper adds credence to proposals for an Arctic focus for managing incoming sunlight as a way to limit greenhouse-driven impacts. (Personally, I don’t see this kind of effort going anywhere unless and until climate impacts trend toward worst-case outcomes.)"
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2 major global warming scientists and IPCC consultants (Dr Murry Salby and Dr Judith Curry) are now backtracking on the AGW theory as well
There is quite a bit of buzz surrounding a talk and pending paper from Prof. Murry Salby the Chair of Climate, of Macquarie University. Aussie Jo Nova has excellent commentary, as has Andrew Bolt in his blog. I’m sure others will weigh in soon.
In a nutshell, the issue is rather simple, yet powerful. Salby is arguing that atmospheric CO2 increase that we observe is a product of temperature increase, and not the other way around, meaning it is a product of natural variation. This goes back to the 800 year lead/lag issue related to the paleo temperature and CO2 graphs Al Gore presented in his movie an An Inconvenient Truth, Jo Nova writes:
Over the last two years he has been looking at C12 and C13 ratios and CO2 levels around the world, and has come to the conclusion that man-made emissions have only a small effect on global CO2 levels. It’s not just that man-made emissions don’t control the climate, they don’t even control global CO2 levels.
Salby is no climatic lightweight, which makes this all the more powerful. He has a strong list of publications here. The abstract for his talk is here and also reprinted below.
http://wattsupwiththat.com/2011/08/05/the-emily-litella-moment-for-climate-science-and-co2/http://judithcurry.com/2011/08/04/carbon-cycle-questions/----------------------------------------------------------------------------------------------------
And finally a major new study of long term data from NASA is causing ripples as well. Climate change forecasts have for years predicted that carbon dioxide would trap heat on Earth, and increases in the gas would lead to a planetwide rise in temperatures, with devastating consequences for the environment. But long-term data from NASA satellites seems to contradict the predictions dramatically. Dr. Roy Spencer is a research scientist at the University of Alabama in Huntsville and U.S. science team leader for the Advanced Microwave Scanning Radiometer on NASA’s Aqua satellite.
"The satellite observations suggest there is much more energy lost to space during and after warming than the climate models show," Spencer said. "There is a huge discrepancy between the data and the forecasts that is especially big over the oceans."
http://www.uah.edu/news/newspages/campusnews.php?id=564------------------------
the study
http://www.mdpi.com/2072-4292/3/8/1603/pdfOn the Misdiagnosis of Surface Temperature Feedbacks from
Variations in Earth’s Radiant Energy Balance