This is just a brief post to point to a few analyses of the Marcott hockey stick.
The National Journal has a science-lite round up of the paper including this quote:
To be clear, the study finds that temperatures in about a fifth of this historical period were higher than they are today. But the key, said lead author Shaun Marcott of Oregon State University, is that temperatures are shooting through the roof faster than we've ever seen.
"What we found is that temperatures increased in the last hundred years as much as they had cooled in the last six or seven thousand," he said. "In other words, the rate of change is much greater than anything we've seen in the whole Holocene," referring to the current geologic time period, which began around 11,500 years ago.
Meanwhile Rud Istvan, writing at Judy Curry's, notes there's just a small problem with the National Journal's case:
The proxy selection was deliberately weighted toward ‘low frequency’ resolution, since the entire Holocene was being assessed...there is no statistically valid resolution to the combined proxy set for anything less than 300-year periods...
Marcott neglected to tell NPR his methodology did not recognize ‘fast’ century changes at all–until recent thermometer records were spliced onto the 73 paleosites.
David Middleton, at WUWT has more.