Professor Michael Mann, the inventor of the Hockeystick
temperature graph, had a contentious editorial essay
in the January 17th issue of the New
York Times. [The Hockeystick graph purports to show that temperatures of
the last thousand years declined steadily -- until the 20th century, when there
was a sudden large rise.]
I am using the word "inventor" on purpose,
since the Hockeystick is a manufactured item and does not correspond to
well-established historic reality. It does not show the generally beneficial
Medieval Warm Period (MWP) at around 1000 AD, or the calamitous Little Ice Age
(LIA) between about 1400 and 1800. In the absence of any thermometers during
most of this period, the Hockeystick is based on an analysis of so-called proxy
data, mostly tree rings, from before 1000 AD to 1980, where the proxy
temperature suddenly stops and a rapidly rising thermometer record is joined
on.
Since its publication in 1998 and 1999, the hockeystick
graph has had a turbulent history. It was adopted by the IPCC
(UN-Intergovernmental Panel on Climate Change) in its 3rd Assessment Report
(2001) to support the claim of a major anthropogenic global warming (AGW)
during the 20th century. Since then, the IPCC has distanced itself from the
graph, which has been completely discredited.....To Read More......
Editor's Note: You may wish to review The Mann Chronicles.
What appears to be.
ReplyDeleteThe cause of the warming, the end of it, and why temperatures are headed down are offered.
Two primary drivers of average global temperatures explain the reported up and down measurements since before 1900 with 90% accuracy and provide credible estimates back to 1610.
Science says CO2 change is NOT one of the drivers.
The drivers are given at http://agwunveiled.blogspot.com/ which includes eye opening graphs and a plethora of links and sub-links to credible data sources.