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The Medieval Warm Period on Russia's Kola Peninsula
Reference
Kremenetski, K.V., Boettger, T., MacDonald, G.M., Vaschalova, T., Sulerzhitsky, L. and Hiller, A. 2004. Medieval climate warming and aridity as indicated by multiproxy evidence from the Kola Peninsula, Russia. Palaeogeography, Palaeoclimatology, Palaeoecology 209: 113-125.

What was done
An international team of Russian, German and U.S. scientists conducted a multiproxy study of climate-related factors in the Khibiny Mountains in the central part of the Kola Peninsula (67-68N, 33-34E), analyzing and dating (1) a series of subfossil soil profiles buried in avalanche cones and (2) living and subfossil pine trees.

What was learned
Kremenetski et al. report that "a period of exceptionally warm and dry conditions commenced at ca. AD 600 and was most pronounced between ca. AD 1000 and 1200," noting that "warmer summer temperatures during this period (coeval with the 'Medieval Warm Period' observed in other parts of Europe) are evident in a 100-140 m upward shift in the pine (Pinus sylvestris L.) limit." Applying a simple environmental lapse rate of 0.7C/100 m to this finding, they say that "this warming can be estimated as being on the order of at least [our italics] 1C compared to the modern summer temperature." In addition, they report that, "on average, the cellulose of pine trees that grew between ca. AD 1000 and 1300 is enriched by 13C values of around 1 [per mil] compared to the modern trees from the region, further suggesting warmer summer climate than at present." What is more, they report "there was also a stabilization of slopes on avalanche cones and formation of soils on them" during this warmer and drier period, noting last of all that "this period of warming extends to northwestern Russia as well as other parts of Europe."

What it means
These results represent yet another of the rapidly accumulating nails that will ultimately be found to secure the coffin of the IPCC-endorsed "hockeystick" temperature record of Mann and colleagues, which gives absolutely no hint of the existence of the Medieval Warm Period and shows current temperatures towering over those pertaining to the time period of this study.


Reviewed 18 August 2004