As I’m sure everyone’s aware at this point, the IPCC has released its Summary for Policymakers (PDF). We’ll have a piece going up later today [here it is] explaining the basics of what the IPCC is and why you should care. Then Monday we’ll have a piece from Andrew Dessler on what the report says and how/whether it’s changed from the 2001 report.

For now, here are a few relevant quotes from the SPM, which I’ve stolen whole hog from Deltoid.

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Here’s the heart of the matter:

Most of the observed increase in globally averaged temperatures since the mid-20th century is very likely [defined as >90% probability] due to the observed increase in anthropogenic greenhouse gas concentrations.

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In other words, there’s not much reasonable doubt left that human beings are driving global warming.

Here’s the deal on projected warming:

Best estimates and likely ranges for globally average surface air warming [by the end of the century] for six SRES emissions marker scenarios are given in this assessment and are shown in Table SPM-2. For example, the best estimate for the low scenario (B1) is 1.8°C (likely range is 1.1°C to 2.9°C), and the best estimate for the high scenario (A1FI) is 4.0°C (likely range is 2.4°C to 6.4°C). Although these projections are broadly consistent with the span quoted in the TAR (1.4 to 5.8°C), they are not directly comparable.

Got that?

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On hurricanes, it turns out the IPCC and the WMO statements aren’t that far apart after all, according to Pielke Jr.

One of the interesting stories in all this is just how off-base some of the early media reports were. We’ll see if post-release coverage is any better.