Paleomonsoon Variability

Wed, 11 Feb 2026, 13:00 CEST

Conveners: Ran Feng & Mary Gagen

Paleomonsoon variability provides insights into the drivers of monsoon variability and helps predict future changes in monsoon behavior, which are vital for agriculture and water resources.

Guest speakers:

• Hu Yongyun (Peking University, China)
• Hai Cheng (Xi’an Jiaotong University, China)

Variations of the global monsoon system over tectonic timescales

Yongyun Hu

The global monsoon system consists of regional monsoons. The concept of the global monsoon reflects the dominant mode of coherent annual variations of precipitation and atmospheric circulations in the tropics and subtropics. In this talk, I will show simulations, together with geological proxies, that the global monsoon system has undergone super-cycles in the Phanerozoic, closely following the supercontinent cycle. I will also demonstrate that global monsoon variations over tectonic timescale are governed by continental configurations: tropical continental area, continental latitudinal location, and continental fragmentation, while temperature or CO₂ concentration has little impact on monsoon variations.

Asian summer monsoon dynamics across various "Quaternary" timescales

Hai Cheng

The Asian Summer Monsoon (ASM) is the largest monsoon system on Earth, influencing the lives of billions across the region. Understanding its variability across timescales is therefore essential for assessing both past climate dynamics and future hydroclimatic risks. Over the past two decades, advances in U/Th and U/Pb dating techniques have propelled cave-based proxy records to the forefront of ASM research. Drawing from these new generation of cave oxygen isotope (δ¹⁸O) records, this presentation explores a number of key outstanding issues in Quaternary ASM dynamics across a wide range of timescales from seasonal to tectonic. I highlight, in particular, the Mid-Pleistocene Transition (MPT) in the ASM; the prevailing precessional rhythm observed across the ASM domain and their distinct spatial phasing variations – the emerging paradigm of "monsoon system science"; the coupling of the ASM with the Atlantic Meridional Overturning Circulation (AMOC) on multiple-timescales; potential roles for low-latitude and Southern Hemisphere triggers in abrupt climate change; and early warning signals prior ASM tippings in cave records and their future implications. The presentation also touches on cross-timescale interactions within the monsoon system and offers perspectives on evolving monsoon theory.