Michael Mann and the MWP – From Denial to Acceptance?29. November 2009 | Von Rudolf Kipp | Kategorie: Blog
Last Friday Michael Mann, father of the infamous hockey-stick, has astonished the scientific community with his publication Global Signatures and Dynamical Origins of the Little Ice Age and Medieval Climate Anomaly. In this paper Mann admits, what he was trying to erase in his former works. The existence of a medieval warm period.
What at first glance appears like a 180° turn, is on the second view just new attempt in making the MWP appear like a local event:
The Medieval period is found to display warmth that matches or exceeds that of the past decade in some regions, but which falls well below recent levels globally.
Which is exactly the statement you get from the alarmists when you point out, that publications show warmer periods in the medieval time. The COMNISPA-reconstruction from the central Alps? Local event. Multiproxy record from the Gulf of Mexico? Central Chile, Iceland, East China, Spain, South Africa, Antarctica, Greenland, Kanada? All just local records. A global reconstruction based on non-treering proxies? Published in a journal with “dubious track record” and – you’ve already guessed it – based on 18 local temperature records. What you learn quite quickly when discussing with AGW believers is, that hundreds of local measurements from all over the globe will always be local. To show global warming on the other hand, some North American Bristlecone Pines or even one single tree in Siberia is more than sufficient to represent the global temperature .
To help you drawing your own conclusions, some temperature records showing the existence of a warmer than today medieval period are displayed in the following map. Just click on the images to receive more information on the single records.