Precipitation and Northern Hemisphere regimes

Abstract Rainfall anomalies in a longterm integration of general circulation model highlight the non‐stationarity of the ocean–atmosphere coupling in the North Atlantic which becomes manifest in two regimes. Anti‐correlations between the precipitation in the tropical and subtropical western Atlantic illustrate the changes of the Hadley cell with El Niño/Southern Oscillation (ENSO).The precipitation anomaly pattern in the north eastern Atlantic resembles variations of the North Atlantic storm track and the North Atlantic Oscillation (NAO). In the hemispheric regime, where 40% of the NAO variability can be explained by ENSO, both precipitation pattern are connected, whereas in the regional regime the ENSO‐link with the North Atlantic storm track and the subtropical 500 hPa geopotential height disappears. Copyright © 2004 Royal Meteorological Society. Published by Elsevier Ltd. All rights reserved.