Numerous studies have demonstrated statistical associations between the El Nino-Southern Oscillation (ENSO) and precipitation in the Mediterranean basin (southern Europe, North Africa, Anatolia, and the Middle East). The dynamical bases for these teleconnections have yet to be identified. The North African-Asian (NAA) jet extends from the subtropical Atlantic Ocean across North Africa, the Mediterranean, South Asia and Japan to the North Pacific Ocean. Atmospheric jets, such as the NAA jet, have been shown to act as waveguides to atmospheric Rossby wave disturbances and, therefore, to create teleconnections between widely separated regions.
The Mediterranean basin lies in the path of the NAA jet. In their previous work, these investigators showed that the NAA jet is modulated throughout the year by conditions in the equatorial Pacific associated with ENSO. This teleconnection between ENSO and the NAA jet appears to be mediated by stationary barotropic Rossby waves.
This project will examine the hypothesis that the ENSO-Mediterranean teleconnection is the result of changes in the NAA jet caused by ENSO. Observations and a hierarchy of models will be used to investigate the dynamics of the ENSO-NAA jet teleconnection and to determine the extent to which precipitation in the Mediterranean region is controlled by ENSO-modulated changes to the NAA jet.
The broader impacts and the societal relevance of this research are in the economic, social and epidemiological importance of climate, and especially precipitation, variability in the Mediterranean region.
