Divergent Evolution of Glaciation Across High‐Mountain Asia During the Last Four Glacial‐Interglacial Cycles

Glaciers over High‐Mountain Asia (HMA) provide a critical window into past climate change and the linkage between high and low‐latitude glaciation, but how glaciers may have varied during past glacial‐interglacial cycles remains elusive. Here, we reconstruct the timing and extent of glaciations for the last 425 kyr over HMA, using a climate‐glaciation simulation constrained by observations and glacial geologic evidence. We illustrate that there were multiple alpine‐style glaciations comparable in extent to those during the last glacial maximum during the last four glacial‐interglacial cycles. The extent and timing of glaciations vary across HMA, especially between the westerly influenced northern and the monsoonal‐influenced southern HMA. The ∼23‐kyr periodicity dominates HMA glaciation due to the critical role of precession in regulating summer temperature and precipitation. Our results, in addition to helping to fill the incomplete glacial geologic record, provide a framework to test hypotheses linking orbital‐scale climate, glaciation, and landscape evolution over HMA. Plain Language Summary Glaciers are sensitive indicators of climate change and sculpting the landscape we observe today, but there is an incomplete picture of how glaciers over High‐Mountain Asia (HMA) might vary during past glacial‐interglacial cycles. Here, we provide the first geological evidence‐constrained scenario on glaciation evolution over HMA during the last four glacial‐interglacial cycles. We illustrate that there were multiple significant glaciations masked by extensive valley glaciers and expanded ice caps for the last 425 kyr, but a continental‐scale ice sheet did not develop. Meantime, the ∼23‐kyr periodicity dominates HMA glaciation, in contrast to the 100‐kyr cycle for the Northern Hemisphere ice sheets. Moreover, the extent and timing of glaciations vary across HMA, especially between the westerly influenced northern and monsoonal‐influenced southern HMA. Key Points There were multiple glacier advances comparable in extent to those during marine isotope stage (MIS) 2 during the last 425 kyr The ∼23‐kyr periodicity dominates High‐Mountain Asia (HMA) glaciation during the last four glacial‐interglacial cycles Glaciations vary greatly between the westerly influenced northern and monsoonal‐influenced southern HMA