Decoupled Indian summer monsoon intensity and effective moisture since the last glaciation in Southwest China

Zhang, T., Yang, X., Peng, J., Zhou, Q., Toney, J. , Liu, H. and Xie, Y. (2023) Decoupled Indian summer monsoon intensity and effective moisture since the last glaciation in Southwest China. Geophysical Research Letters, 50(10), e2023GL103297. (doi: 10.1029/2023GL103297)

Abstract

Effective moisture (EM) distribution in the Indian summer monsoon (ISM) region is strongly related to regional topography. An understanding of climate change and the interactions between climate variables can help predict future climate variations. Here, we reconstruct a stack EM record for Southwest China over the past 90 kyr using environmental magnetism in lake sediment. The EM in Southwest China at the orbital scale was closely linked to precession-induced change in North Hemisphere solar insolation, as well as the ISM variability. However, at the glacial-interglacial scale, it was decoupled with ISM intensity, being wetter during glacial periods (weakened ISM) and drier during interglacial periods (enhanced ISM). Combined with modern meteorological observations, we suggest that the topographical barrier effect and temperature induced dryness are responsible for the decoupling between ISM intensity and EM. The terrestrial topography and temperature strongly influence EM distribution by altering the dynamics of onshore airflow and evapotranspiration.

• Item Type: Articles
• Additional Information: This research is supported by the projects of National Second Expedition to the Tibetan Plateau (2019QZKK0707), Guangdong Province Introduced Innovative R&D Team of Geological Processes and Natural Disasters around the South China Sea (2016ZT06N331), the projects of National Natural Science Foundation of China (41872217, 41672162, 41904068).
• Keywords: Effective moisture, Southwest China, hematite‐goethite, environmental magnetism, the last glacial.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Toney, Professor Jaime
• Authors: Zhang, T., Yang, X., Peng, J., Zhou, Q., Toney, J., Liu, H., and Xie, Y.
• College/School: College of Science and Engineering > School of Geographical and Earth Sciences
• Journal Name: Geophysical Research Letters
• Publisher: Wiley
• ISSN: 0094-8276
• ISSN (Online): 1944-8007
• Published Online: 24 May 2023
• Copyright Holders: Copyright © 2023 The Authors
• First Published: First published in Geophysical Research Letters 50(10): e2023GL103297
• Publisher Policy: Reproduced under a Creative Commons License
• Data DOI: 10.1594/PANGAEA.958273