03-12-2006 - Earth

sagar: Author=’Jorge Salazar’ program=’4816′ video=”_JB:_ This is Earth & Sky. One of the largest climate changes observed in the last century was in the Sahel region of Africa.

_DB:_ That region of mostly grasslands suffered severe drought in the 1970s and 80s, in which millions of people died. Research meteorologist ” Thomas Delworth”:http://www.gfdl.noaa.gov/~td/ helped develop a computer model that simulates the past and future climate of Africa’s Sahel.

_JB:_ Delworth told Earth & Sky that as North Atlantic waters warm up, the rain belt is pulled north over the Sahel. But If the South Atlantic warms more than the North Atlantic, rain moves south and leaves the Sahel drier. Delworth added that greenhouse gases and aerosols – particles of dust, soot, and emissions from industry – also play a key role in the climate of Africa’s Sahel region.

_Thomas Delworth:_ Our model, one of the unique aspects, is that in the 20th century, in response solely to increasing greenhouse gases and aerosols, we simulate a drying trend in the Sahelian region of Africa, which looks a lot like the observed record. And so, therefore, we can place some credibility, I think, in the results of this model, because it reproduces the observations so well.

_DB:_ Delworth said this same model projects a continued drying of the Sahel – important information if those living in the region are to prepare. For more, come to earthsky.org. Thanks today to NOAA, the National Oceanic and Atmospheric Administration. We’re Block and Byrd for Earth & Sky.

Written by EarthSky