Contrasting evolution of the Arabian Sea and Pacific Ocean oxygen minimum zones during the Miocene.

ABSTRACT: Ocean oxygen minimum zones have expanded since the mid-20^th century, yet their future remains uncertain. Previous studies show that the eastern tropical North Pacific was well oxygenated during the warm Miocene Climatic Optimum (17.0-14.8 Ma), suggesting better oxygenation under climatic warming. To explore whether this response was global, we reconstruct Miocene oxygenation in the second largest oxygen minimum zone, the Arabian Sea. Trace elements and nitrogen isotopes in planktonic foraminifera show that the Arabian Sea was also better oxygenated during the Miocene Climatic Optimum than today. However, deoxygenation history and establishment of a true oxygen deficient zone following the Miocene cooling lagged in the Arabian Sea, indicating the important role of regional oceano

SUBMITTER: Hess AV 

PROVIDER: S-EPMC12811131 | biostudies-literature | 2026

REPOSITORIES: biostudies-literature