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The Medieval Warm Period in Northwest Lithuania
Stancikaite, M., Sinkunas, P., Risberg, J., Seiriene, V., Blazauskas, N., Jarockis, R., Karlsson, S. and Miller, U. 2009. Human activity and the environment during the Late Iron Age and Middle Ages at the Impiltis archaeological site, NW Lithuania. Quaternary International 203: 74-90.

What was done
The authors carried out interdisciplinary research at the Impiltis hill fort and settlement area of Northwest Lithuania in order "to study the climate and the human impact on the landscape, the development of the settlement and the hill fort, the types of agriculture employed there, and changes in the local economy," while simultaneously "interpreted in the obtained data [were] the environmental variations produced by global climatic shifts."

What was learned
Stancikaite et al. determined that "the transition from the first to the second millennium AD, also the onset of the 'Medieval Warm Period,' coincided with a period of intensive human activity at the Impiltis hill fort and settlement area." There was at that time, as they continue, "a high intensity of farming activities, which were supported by favorable climatic conditions and included the existence of permanent agricultural fields as well as the earliest record of rye cultivation in NW Lithuania."

The "period of most prominent human activity in the Impiltis," as the eight researchers describe it, "was dated back to about 1050-1250 AD," and they say that "the favorable climatic conditions of [this] 'Medieval Warm Period' may have supported human activity during its maximum phase," which inference, in their words, "correlates well with the chronology of the hill fort and settlement prosperity as represented in data collected from the site." Thereafter, they suggest "it is possible that the ensuing gradual regression of human activity was caused, in part, by the climatic deterioration known as the 'Little Ice Age'."

What it means
Once again, we have a treasure trove of new real-world evidence for what Stancikaite et al. describe as "remarkable changes" in Northwest Lithuania's "environment and population history" that "took place in the context of worldwide climatic fluctuations," which were, of course, totally independent of any fluctuations in the atmosphere's CO2 concentration (since there were no signification CO2 fluctuations over this period). And these observations suggest that the reverse of that "worldwide climatic fluctuation" -- earth's recovery from the global chill of the Little Ice Age (which led to the creation of the Current Warm Period) -- has also had nothing to do with concomitant changes in the atmosphere's CO2 concentration, revealing the weakness of climate-alarmist claims to the contrary.

Reviewed 24 March 2010