Abrupt Warming

Ohio State
Lead author: Lonnie G. Thompson

The warming around Earth's tropical belt is a signal suggesting that the "climate system has exceeded a critical threshold," which has sent tropical-zone glaciers in full retreat and will melt them completely "in the near future"
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Increased Hurricanes

National Center for Atmospheric Research
Lead authors: Kevin Trenberth, Dennis Shea
Where published: Geophysical Research Letters

Global warming provided much of the ocean heat that fueled last year's record-setting hurricane season ... global warming accounted for nearly half of the above-normal ocean heating that fed 15 Atlantic hurricanes ... Natural climate cycles were only a minor factor in the excess warming
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Warmest in 400 Years

National Academy of Science
Chair: Gerald R. North

sufficient evidence from tree rings, boreholes, retreating glaciers, and other "proxies" of past surface temperatures to say with a high level of confidence that the last few decades of the 20th century were warmer than any comparable period in the last 400 years ... scientists' reconstructions of Northern Hemisphere surface temperatures for the past thousand years are generally consistent ... multiple lines of evidence supporting the conclusion that current warming is occurring in response to human activities
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Thawing Permafrost

Russian Academy of Sciences, University of Florida
Lead authors: Sergey Zimov, Edward Schuur
Where Published: Science Magazine

Thawing permafrost in the Arctic could play a role in fueling global warming ... The reservoir is very large and dangerous ... frozen soils across a large swath of Siberia and Alaska hold nearly 500 billion tons (454 billion metric tons) of carbon—or two-thirds current atmospheric levels.
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