Miocene African topography induces decoupling of Somali Jet and South Asian summer monsoon rainfall.

ABSTRACT: The Miocene epoch, marked by significant tectonic and climatic shifts, presents a unique period to study the evolution of South Asian summer monsoon (SASM) dynamics. Previous studies have shown conflicting evidence: wind proxies from the western Arabian Sea suggest a weaker Somali Jet during the Middle Miocene compared to the Late Miocene, while rain-related records indicate increased SASM rainfall. This apparent decoupling of monsoonal winds and rainfall has challenged our understanding of SASM variability. Here, using the fully coupled EC-Earth3 model, we identify a key driver of this decoupling: changes in African topography rather than other external forcings such as CO₂ change. Our simulations reveal that changes in Miocene African topography weakened the cross-equatorial S

SUBMITTER: Han Z 

PROVIDER: S-EPMC12322274 | biostudies-literature | 2025 Aug

REPOSITORIES: biostudies-literature