Reduced Asian monsoon influence on Mediterranean summers in a warmer climate

Abstract

The Mediterranean is highly vulnerable to summer heatwaves and wildfires, with its climate strongly influenced by large-scale subsidence linked to the South Asian summer monsoon. However, how this Mediterranean–monsoon teleconnection will respond to global warming remains poorly understood. Here we investigate the future evolution of the South Asian summer monsoon’s remote influence on Mediterranean summer climate under global warming using large ensemble simulations under a high-emission scenario. The monsoon influence on Mediterranean summer circulation weakens substantially under global warming, with the ensemble mean of correlation coefficient decreasing from 0.41 (P < 0.001) to near zero. This weakening results from the westward expansion of the monsoon-induced zonal thermal structure associated with elevated monsoon convection and a reduction in meridional wind anomalies through local dynamical feedbacks. The weakened monsoon-induced subsidence response further reduces the monsoon-related Mediterranean summer precipitation variability, with explained variance decreasing from 14.2% to 5.1%. Our results suggest that global warming will weaken the interannual coupling between the South Asian summer monsoon and Mediterranean summer climate, emphasizing the role of changing atmospheric dynamics in reshaping large-scale climate teleconnections. A warming climate may weaken the influence of the South Asian monsoon on Mediterranean summers, as shifting heat and wind patterns reduce its impact on regional weather, according to climate model projections under a high-emissions scenario.