Changes in the Asian ITCZ During the Last Interglacial, the Last Glacial Maximum, and the Mid‐Holocene

Abstract

AbstractWe investigate the position and intensity changes of the Intertropical Convergence Zone (ITCZ) over Asia (50°E−135°E) relative to the preindustrial period annually and seasonally during the Last Interglacial (LIG), Last Glacial Maximum (LGM), and mid‐Holocene (MH) using available models from phases 3 and 4 of the Paleoclimate Modeling Intercomparison Project. The multi‐model mean shows that the June–July–August ITCZ variations generally dominate the annual changes. The Asian ITCZ shifts northward over western Asia and southward over the eastern side in both the LIG and MH, and the opposite occurs in the LGM. Its intensity varies with longitude similarly for the LIG and MH and generally weakens in the LGM. Precipitation changes associated directly with ITCZ indices are primarily caused by the dynamic term in the LIG and MH, while both dynamic and thermodynamic terms play roles in the LGM, with major contributions from the convergence components.