CO2/H2O and orbitally driven climate variability over central Asia through the Holocene

Over central Asia, the amplitude of the summer-winter seasonal cycle is greater than today in all simulations but exhibits two distinct maxima at 9000 and 6000 BP. Simulated precipitation and snow accumulation over central Asia are markedly higher during the early mid Holocene and are oscillatory, exhibiting peaks at 8000-7500 and 4500 BP (the Atlantic and Subboreal times, respectively). CO2/H2O forcing and orbital forcing combine to drive temperature oscillations over central Asia which, in turn, regulate relative humidity and changes in surface hydrology. Correlation between simulated results and proxy records from across Asia suggest that CO2/H2O and orbital forcing are dominant factors driving fluctuations of large-scale, central Asian climate through the Holocene.