Hydroclimatic impacts of ‘8.2-ka event’ in western Indo-Pacific Warm Pool

Abstract The most prominent abrupt climate event during the Holocene, the ‘8.2 ka event’, was characterized by severe cooling at high northern latitudes causing diverse hydroclimate shifts globally. To date, a precise understanding of the hydroclimate response of the Indo-Pacific Warm Pool (IPWP) region to abrupt climate changes in the North Atlantic around 8.2 ka remains elusive. Here we present a high-resolution stable carbon isotope record on foraminifera species Asterorotalia pulchella and sediment characteristics of a marine sediment core from the Kallang River Basin, Singapore. Foraminifer stable isotope data in concert with sedimentological proxies provide coherent evidence of weakened rainfall for ~ 180 years in the western tropical Indo-Pacific region from ~ 8.14 ka to 7.96 ka BP. A robust age model suggests that the timing of the onset of reduced convective activity in the western IPWP region lags the cooling in the North Atlantic and the synchronous droughts in the Asian and Indian monsoon regions, by ~ 100years possibly implying a north-south signal propagation via oceanic route that operates on centennial scales. The termination of the ‘8.2 ka event’, however may have occurred near synchronously between high and low tropical regions at ~ 7.96ka BP possibly linked via both atmospheric and oceanic processes.