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800 Years of Siberian Climate
Kalugin, I., Selegei, V., Goldberg, E. and Seret, G.  2005.  Rhythmic fine-grained sediment deposition in Lake Teletskoye, Altai, Siberia, in relation to regional climate change.  Quaternary International 136: 5-13.

What was done
To date, few paleoclimate records exist for the continental interior of Russia's Siberia.  In the present study, Kalugin et al. analyzed sediment cores from Lake Teletskoye in the Altai Mountains of Southern Siberia (5142.90'N, 8739.50'E) to produce a multi-proxy climate record spanning the past 800 years.

What was learned
Analyses of the multi-proxy record revealed several distinct climatic periods over the past eight centuries.  With respect to temperature, the regional climate was relatively warm with high terrestrial productivity from AD 1210 to 1380.  Thereafter, temperatures cooled, reaching peak deterioration between 1660 and 1700, which time period, in the words of the authors, "corresponds to the age range of the well-known Maunder Minimum (1645-1715)" and is "in agreement with the timing of the Little Ice Age in Europe (1560-1850)."  Recovery to prior-level warmth did not occur until the late 20th century.

With respect to moisture and precipitation, Kalugin et al. state that the period between 1210 an 1480 was more humid than that of today, while the period between 1480 and 1840 was more arid.  In addition, they report three episodes of multi-year drought (1580-1600, 1665-1690 and 1785-1810), which findings are in agreement with other historical data and tree-ring records from the Mongolia-Altai region (Butvilovskii, 1993; Jacoby et al., 1996; Panyushkina et al., 2000).

What it means
This study continues to add to the large body of evidence in support of a global Medieval Warm Period and Little Ice Age, which natural fluctuations are also likely responsible for bringing us the warmth of the Modern Warm Period, as opposed to CO2-induced global warming.  In addition, it proves problematic for the climate-alarmist claim that global warming will lead to more severe droughts, as all of the major multi-year droughts detected in this study occurred during the cool phase of the 800-year record.

Butvilovskii, V.V.  1993.  Paleogeography of the Late Glacial and Holocene on Altai.  Tomsk University, Tomsk.

Jacoby, G.C., D'Arrigo, R.D. and Davaajatms, T.  1996.  Mongolian tree rings and 20th century warming.  Science 273: 771-773.

Panyushkina, I.P., Adamenko, M.F., Ovchinnikov, D.V.  2000.  Dendroclimatic net over Altai Mountains as a base for numerical paleogeographic reconstruction of climate with high time resolution.  In: Problems of Climatic Reconstructions in Pliestocene and Holocene 2.  Institute of Archaeology and Ethnography, Novosibirsk, pp. 413-419.

Reviewed 6 July 2005