Tom Kunich wrote:
>
> "Scores of scientific papers show that the medieval warm period was
> real, global and up to 3C warmer than now. Then, there were no
> glaciers in the tropical Andes: today they're there. There were Viking
> farms in Greenland: now they're under permafrost. There was little ice
> at the North Pole: a Chinese naval squadron sailed right round the
> Arctic in 1421 and found none."
>
But it wasn't a global shift in climate, it was regional. Get the
difference? Regional, not global. The idea there was a global warming
during this time has been shown to be false.
Here's an excerpt of the MWP from the TAR:
As with the “Little Ice Age”, the posited “Medieval Warm Period” appears to
have been less distinct, more moderate in amplitude, and somewhat different
in timing at the hemispheric scale than is typically inferred for the
conventionally-defined European epoch. The Northern Hemisphere mean
temperature estimates of Jones et al. (1998), Mann et al. (1999), and
Crowley and Lowery (2000) show temperatures from the 11th to 14th centuries
to be about 0.2°C warmer than those from the 15th to 19th centuries, but
rather below mid-20th century temperatures. The long-term hemispheric trend
is best described as a modest and irregular cooling from AD 1000 to around
1850 to 1900, followed by an abrupt 20th century warming. Regional evidence
is, however, quite variable. Crowley and Lowery (2000) show that western
Greenland exhibited anomalous warmth locally only around AD 1000 (and to a
lesser extent, around AD 1400), with quite cold conditions during the
latter part of the 11th century, while Scandinavian summer temperatures
appeared relatively warm only during the 11th and early 12th centuries.
Crowley and Lowery (2000) find no evidence for warmth in the tropics.
Regional evidence for medieval warmth elsewhere in the Northern Hemisphere
is so variable that eastern, yet not western, China appears to have been
warm by 20th century standards from the 9th to 13th centuries. The 12th and
14th centuries appear to have been mainly cold in China (**** et al.,
1998a,b; **** and Gong, 2000). The restricted evidence from the Southern
Hemisphere, e.g., the Tasmanian tree-ring temperature reconstruction of
Cook et al. (1999), shows no evidence for a distinct Medieval Warm Period.
http://www.grida.no/climate/ipcc_tar/wg1/070.htm
If you have trouble reading this, I think there's a video of an interpetive
dance on the subject done by the Mark Morris troupe available on YouTube.
It involves pecker-waggling though. Morris is like that.
--
Bill Asher