Seasonal predictability of Kiremt rainfall in coupled general circulation models

TitleSeasonal predictability of Kiremt rainfall in coupled general circulation models
Publication TypeJournal Article
Year of Publication2017
AuthorsGleixner, S, Keenlyside, NS, Demissie, TD, Counillon, F, Wang, Y, Viste, E
JournalEnvironmental Research Letters
Volume12
Number11
Number of Pages114016
Abstract

The Ethiopian economy and population is strongly dependent on rainfall. Operational seasonal predictions for the main rainy season (Kiremt, June–September) are based on statistical approaches with Pacific sea surface temperatures (SST) as the main predictor. Here we analyse dynamical predictions from 11 coupled general circulation models for the Kiremt seasons from 1985–2005 with the forecasts starting from the beginning of May. We find skillful predictions from three of the 11 models, but no model beats a simple linear prediction model based on the predicted Niño3.4 indices. The skill of the individual models for dynamically predicting Kiremt rainfall depends on the strength of the teleconnection between Kiremt rainfall and concurrent Pacific SST in the models. Models that do not simulate this teleconnection fail to capture the observed relationship between Kiremt rainfall and the large-scale Walker circulation.

URLhttp://stacks.iop.org/1748-9326/12/i=11/a=114016
Author Address

1 Geophysical Institute, University of Bergen and Bjerknes Centre for Climate Research, Bergen, Norway

2 Uni Research Climate, Bjerknes Centre for Climate Research, Bergen, Norway

3 Nansen Environmental and Remote Sensing Center, Bjerknes Centre for Climate Research, Bergen, Norway

4 Author to whom any correspondence should be addressed.