We’re not screwed?

Ross McKitrick, Financial Post

[caption id="attachment_1604" align="alignleft" width="620"] Left, global temperature variation over the past 11,000 years based on analysis of fossils from 73 sites around the world, with addition of 20th-century temperature records, from the Marcott et al. Science paper. At right, the same graph without the current temperature records. Sources: left, Science; right, Roger Pielke Jr.[/caption]

11,000-year study’s 20th-century claim is groundless

On March 8, a paper appeared in the prestigious journal Science under the title A reconstruction of regional and global temperature for the past 11,300 years. Temperature reconstructions are nothing new, but papers claiming to be able to go back so far in time are rare, especially ones that promise global and regional coverage.

The new study, by Shaun Marcott, Jeremy Shakun, Peter Clark and Alan Mix, was based on an analysis of 73 long-term proxies, and offered a few interesting results: one familiar (and unremarkable), one odd but probably unimportant, and one new and stunning. The latter was an apparent discovery that 20th-century warming was a wild departure from anything seen in over 11,000 years. News of this finding flew around the world and the authors suddenly became the latest in a long line of celebrity climate scientists.

The trouble is, as they quietly admitted over the weekend, their new and stunning claim is groundless. The real story is only just emerging, and it isn’t pretty.

Read the rest here.