Hydroclimatic Variability in the Panama Bight Region During Termination 1 and the Holocene

Abstract

We have investigated the Holocene climate and vegetation change in the Asian monsoon region using climate model simulations and proxy derived vegetation and climate reconstructions. The simulated mid-Holocene climate is qualitatively in good agreement with the reconstructions. Both methods reveal no systematic and uniform large-scale climate shifts, but asynchronous moisture changes in different sub-areas of the Asian monsoon region. The atmospheric response to the Holocene insolation forcing is strongly modified by ocean-atmosphere interactions, while the interaction between vegetation and atmosphere has minor influence on the large-scale Holocene climate change and is only important at a regional level. Nevertheless, sensitivity simulations reveal that large-scale forest decline in the Asian monsoon region leads to substantial losses in regional precipitation. During the Holocene, substantial vegetation changes are confined to the fringe zone of the Asian monsoon area and to the Tibetan Plateau, where simulated forest fraction has decreased by approx. 15 % and 30 % since mid-Holocene, respectively.