The Southern Hemisphere Westerly Winds (SWW) have been suggested to exert acritical influence on global climate through the wind-driven upwelling of deepwater in the Southern Ocean and the potentially resulting atmosphericCO2 variations. The investigation of the temporal and spatial evolutionof the SWW along with forcings and feedbacks remains a significant challengein climate research. In this study, the evolution of the SWW under orbitalforcing from the mid-Holocene (7 kyr BP) to pre-industrial modern times (250 yr BP) is examined with transient experiments using thecomprehensive coupled global climate model CCSM3. In addition, a model inter-comparison iscarried out using orbitally forced Holocene transient simulations from fourother coupled global climate models. Analyses and comparison of the modelresults suggest that the annual and seasonal mean SWW were subject to anoverall strengthening and poleward shifting trend during the course of themid-to-late Holocene under the influence of orbital forcing, except for theaustral spring season, where the SWW exhibited an opposite trend of shiftingtowards the equator.
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