Responses of East Asian Winter Monsoon‐Australian Summer Monsoon to Local and Remote Orbital Forcing During Holocene. Issue 10 (24th May 2022)

• Record Type: Journal Article
• Authors: Wen, Qin; Yan, Mi; Liu, Zhengyu; Liu, Jian
• Is Part Of: Geophysical research letters. Volume 49:Issue 10(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-05-24
• Subjects: orbital‐induced insolation -- East Asian winter monsoon -- Australian summer monsoon -- local insolation -- remote insolation; Geophysics -- Periodicals; Planets -- Periodicals; Lunar geology -- Periodicals; 550
• DOI: 10.1029/2022GL098865
• Languages: English
• ISSNs: 0094-8276

Abstract

Abstract: Here, we perform a set of sensitivity experiments in a climate model to quantify the impacts of local and remote insolation changes on the East Asian winter monsoon (EASM) and Australian summer monsoon (AusSM) at early and middle Holocene relative to the present. We show that the EAWM during Holocene is enhanced, driven overwhelmingly by the local insolation change in the low to mid‐latitude Northern Hemisphere (NH) through its impacts on land‐sea thermal contrast, with the NH high latitude forcing playing a negligible role. In contrast, the AusSM is also enhanced, opposite to the local insolation forcing, because the local forcing impact is overwhelmed by that from the remote forcing of both NH low latitude and Southern Hemisphere high latitude, with the latter dominating in the mid‐Holocene. Plain Language Summary: Orbital‐induced insolation variations play an important role in driving monsoon changes at geological time scales. One key issue that has remained outstanding is whether the monsoon is driven by local insolation from the corresponding hemisphere or remote insolation from the other hemisphere. For the first time, this work systematically isolates local and remote insolation impacts on East Asian winter monsoon (EAWM) and Australian summer monsoon (AusSM) during the early and middle Holocene. Our study suggests that the EAWM is enhanced during Holocene compared with PI by local insolation forcing over the Northern Hemisphere (NH) tropical‐mid‐latitude region. In contrast, the weakening impact on AusSM by local insolation is completely overwhelmed by the enhancement of the remote forcing from both the NH low latitude and Southern Hemisphere high latitude. Key Points: The first study to isolate the local and remote insolation effect on East Asian winter monsoon and Australian summer monsoon The enhanced East Asian winter monsoon is predominantly driven by local insolation The Australian summer monsoon is enhanced by remote forcing from northern Hemisphere low latitude and Southern Hemisphere high latitude