Wednesday, 17 January 2007: 10:15 AM
Evaluating IPCC rainfall and food aid tendencies for food insecure Africa
214C (Henry B. Gonzalez Convention Center)
We report on an analysis of IPCC precipitation and food aid factors for nineteen food insecure countries in Africa. A multi-model examination of the latest 4th Assessment Report (AR4) IPCC model simulations suggest strikingly good correspondence with observed regional drying tendencies in the Sahel and southern Africa. The average response of 132 simulations reasonably recreates the post-1960 decline in rainfall. Over the first half of the 21st century the aggregate model response suggests fairly level precipitation in these areas, followed by declines beginning around 2030 (Sahel) and 2070 (Southern Africa). While considerable uncertainty of course remains, the hindcast accuracy of the model ensemble means suggests some confidence in the future projections. Eastern Africa may be different. Past model precipitation is inversely related to the observed low frequency precipitation variations. This discrepancy and the observed (contrary) relationships between eastern African precipitation and oceanic rainfall suggest that a warming Indian Ocean will likely be related to modest decreases in rainfall over the Greater Horn of Africa. We quantify this hypothesis and relate statistically tropical oceanic precipitation to eastern African rainfall. Rainfall projections for eastern, southern and western Africa are linked to models of food aid, and estimates of food aid needs over the next 30 years are provided. The results argue compellingly for an increased commitment to developing agricultural capacity in Africa.