HR: 1340h
AN: GC33A-0946    [Abstracts]
TI: Examining the potential impact of a warming ocean on food insecure Africa: concerns and mechanisms for abrupt climate change
AU: * Funk, C
EM: chris@geog.ucsb.edu
AF: Climate Hazard Group, Geography Department UC Santa Barbara, Santa Barbara, CA 93106,
AU: Dettinger, M
EM: mdettinger@ucsd.edu
AF: USGS/Scripps, Scripps Inst of Oceanography, La Jolla, CA 92093, United States
AU: Verdin, J
EM: verdin@usgs.gov
AF: US Geological Survey, National Center for EROS, Sioux Falls, SD 57198, United States
AB: Given that more than 200 million sub-Saharan Africans are food insecure, abrupt climate change in Africa could be devastating. Recent observations for eastern and southern Africa suggest substantial declines in main growing season rainfall over the past 20 years. In this talk we present research from a multi-year study that examined the causes and implications of these drying trends. Our statistical and dynamic modeling results suggest that warming in the Indian Ocean has been linked to increased oceanic convection and disruptions in onshore moisture transports. These moisture transport disruptions, in turn, are probably associated with an increased frequency in agricultural drought in sub-tropical countries along Africa's eastern seaboard. This 'warm ocean-dry Africa' dipole appears to be a major driver of decadal variability. An evaluation of 11 climate change models suggests that increased tropical Indian Ocean precipitation, and the associated moisture transport disruptions, may in fact be anthropogenic, accounting for at least part of the regional drought tendencies in eastern and southern Africa over the past 20 years. These simulations also suggest continued increases in oceanic convection will be very likely over the next century. This diabatic forcing will likely produce continuing rainfall declines across 7 food insecure nations. These drying trends, combined with declining per capita agricultural capacity, are likely to contribute to a ~250 percent increase in food shortages over the next 30 years. Modest agricultural and market development, however, could alleviate the food problem substantially.
DE: 1605 Abrupt/rapid climate change (4901, 8408)
DE: 1616 Climate variability (1635, 3305, 3309, 4215, 4513)
DE: 1630 Impacts of global change (1225)
DE: 1637 Regional climate change
DE: 1812 Drought
SC: Global Environmental Change [GC]
MN: 2007 Fall Meeting