From The Hockey Stick To Going Vertical With The Wheelchair - From 20000 BCE To 2100 AD

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The big picture (or as some call it: the Wheelchair): Global average temperature since the last ice age (20,000 BC) up to the not-too distant future (2100) under a middle-of-the-road emission scenario.

Earlier this month an article was published in Science about a temperature reconstruction regarding the past 11,000 years. The lead author is Shaun Marcott from Oregon State University and the second author Jeremy Shakun, who may be familiar from the interesting study that was published last year on the relationship between CO2 and temperature during the last deglaciation. The temperature reconstruction of Marcott is the first one that covers the entire period of the Holocene. Naturally this reconstruction is not perfect, and some details will probably change in the future. A normal part of the scientific process.

The temperature reconstruction ends mid-20th century, so the rapid temperature rise since 1850 is clearly visible in the graphs presented in their study. nd what do we see? Again something that looks like a hockey stick as in the graph from Mann et al 2008.

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EDIT

Patterns in temperature reconstructions which resemble a hockey stick, are fervently contested on climate skeptic websites. The Marcott et al reconstruction is no exception. For example, it is hard to keep track of the number of posts WUWT dedicated to this study, and the statistical wonderboy McIntyre is also energetically producing blog posts. Otherwise the general public might get the impression that humans are strongly influencing the climate and apparently that is not a desirable impression.

EDIT

http://ourchangingclimate.wordpress.com/2013/03/19/the-two-epochs-of-marcott/