The influence of the North Atlantic Oscillation and European circulation regimes on the daily to interannual variability of winter precipitation in Israel

Abstract

AbstractThe arid climate of the Middle East means that variations in rainfall on all timescales from days to years have enormous impact on the people who live in the region. Understanding this variability is crucial if we are to interpret model simulations of the region's climate and make meaningful predictions of how the climate may change in the future. This study investigates the links between the European synoptic regimes that favour rainfall in Israel, interannual variability in the Mediterranean storm track, and large‐scale modes of variability such as the North Atlantic Oscillation (NAO). It is shown that particular European circulation regimes favour rainfall in Israel, and that these regimes occur more frequently when the NAO is in its positive phase. This is reflected by increased likelihood of very high rainfall totals in the Middle East during NAO positive winters. In contrast, the circulation regimes associated with an increased probability of dry weather are not associated with NAO negative conditions. This non‐linearity, along with the known lack of stationarity in NAO teleconnections explains the weak correlation between the NAO index and precipitation in the Jordan and Israel. Copyright © 2011 Royal Meteorological Society