As anyone who reads my posts knows, I am a big fan of the IPCC reports. They are the best summary of what the scientific community knows about climate change and how confidently we know it.

A recent article (subscription required, sorry) in Science suggests that some scientists view the IPCC as overly cautious:

In the latest report, its fourth since 1990, the IPCC spoke for scientists in a calm, predictably conservative tone (Science, 9 February, p. 754). It is, after all, an exhaustive, many-tiered assessment of the state of climate science based exclusively on the published literature. In IPCC's Working Group I report on the physical science of climate, 600 authors contributed to an 11-chapter report that drew 30,000 comments from reviewers. The report was in turn boiled down to a 21-page "Summary for Policymakers" (SPM). Its central projection of sea-level rise by the century's end -- 0.34 meter -- came within 10% of the 2001 number. And by getting a better handle on some uncertainties, it even brought down the upper limit of its projected range, from 0.89 to 0.59 meter.

The SPM did add that "larger values [of sea-level rise] cannot be excluded." Whatever has accelerated ice-sheet flow to the sea, the report said, might really take off with further warming -- or not. "Understanding of these effects is too limited" to put a number on what might happen at the high end of sea-level rise, it concluded. Lacking such a number, the media tended to go with the comforting 0.34-meter projection or ignore sea level altogether.

I have two conflicting views of this.