Quantitative Holocene climatic reconstruction from Arctic Russia

Vegetation changes reflected in fossil pollen spectra are a primary source of information about climate fluctuations in the past. A statistical-inform ation (transfer function) method based on the correlation of recent pollen spectra with modern climate conditions has been used to reconstruct Holocen e climatic changes from fossil pollen. Climatic variables used for the reco nstructions are the mean annual, January, July temperatures and annual prec ipitation. Peat sections with pollen and C-14 data from the Arctic Russia w ere used for the reconstructions. The reconstructed climate fluctuations ar e similar to the climate changes obtained from many sites in the former USS R. A clear signal for Younger Dryas cooling, 11,000-10,000 yr BP and early Preboreal warming is apparent. The early Preboreal (10,000-9000 yr BP) was the warmest time for sites from modern coastal and island areas. The warm i nterval occurred in the Boreal period, about 8500 yr BP. According to the r econstructions the warmest time for non-coastal areas was the last half of Atlantic period, 6000-4500 yr BP. Other warm intervals were reconstructed a bout 3500 and 1000 yr BP. Reconstructions show that warming periods are pri marily defined as times of increased summer temperatures, and cooling perio ds as time of decreased winter temperatures. The precipitation followed the temperatures: during the warming periods precipitation increased and durin g the cooling periods it decreased. Precipitation maximum, about 100 mm hig her than present, are reconstructed for the warmest interval, 6000-4500 yr BP at all sites.