Etesians and the summer circulation over East Mediterranean in Coupled Model Intercomparison Project Phase 5 simulations: Connections to the Indian summer monsoon

摘要

Etesians are north to south direction winds in the lower atmosphere, blowing over the Aegean basin from early summer to early autumn. They are an important circulation component for the East Mediterranean (EMED) area, linked to the subsidence and ascent circulation over EMED and the extended Indian monsoon region, respectively. In this study we investigate the evolution of Etesian days and the associated wind speed (10 m) over the recent past (1979-2005) in simulations from Earth System Models (ESMs) available from the Coupled Model Intercomparison Project Phase 5. Results from this analysis are compared to the ERA-Interim reanalysis. Moreover, we study the connection of the Etesians to the atmospheric circulation over EMED and the wider Indian monsoon area, in particular over the west Indian summer monsoon (wISM) and the Bay of Bengal (BoB). Our findings suggest that while the ESMs underestimate the wind speed of the Etesians, their frequency and summer cycle are in good agreement to reanalysis. ESMs can accurately represent the summer atmospheric circulation and depict the connection between EMED and Indian summer monsoon (ISM), capturing the link between them. Finally, we highlight here the capability and efficiency of ESMs in representing the climatology of Etesians and related atmospheric circulation.