The South Asian summer monsoon has long shaped Mediterranean climate thousands of kilometers away through the “monsoon–desert” mechanism. Intense monsoon convection releases atmospheric heat, triggering circulation changes that promote sinking air over the Mediterranean, suppressing clouds and rainfall.

A research team led by Prof. ZHOU Tianjun at the Institute of Atmospheric Physics of the Chinese Academy of Sciences combined observations, climate model simulations, and numerical experiments to examine how global warming would affect this monsoon–Mediterranean connection. Results, published in Nature Geoscience, showed remarkably consistent findings: in 97.5% of CESM1 simulations, the monsoon’s effect on Mediterranean atmospheric circulation weakened significantly.

The correlation between monsoon heating and mid-tropospheric subsidence declined from approximately 0.4 to essentially zero by century’s end.

Underlying Processes

Researchers identified key changes. As climate warms, deep monsoon convection shifts higher in the troposphere—from about 452 hPa to 417 hPa in simulations. This reduces east-west temperature contrast over the Mediterranean, suppressing subsidence. Locally, weakened sinking motion reduces northerly winds through atmospheric dynamics, reinforcing the remote effect.

Regarding rainfall, the monsoon currently explains about 14.2% of Mediterranean summer rainfall variance. This fraction drops to 5.1% under future warming, though overall rainfall variability persists from other sources.

Prof. ZHOU noted: “Global warming can reorganize dynamical links between distant climate system parts.” Dr. YU Hanzhao, lead author, emphasized that “atmospheric connections robust today may not persist under global warming.”

Journal: Nature Geoscience
DOI: 10.1038/s41561-026-02091-1
Article Title: Reduced Asian monsoon influence on Mediterranean summers in a warmer climate
Publication Date: 23-Sep-2026

Source: EurekAlert