Mali Climate Change Projections

Mali lies just south of the Sahara. The country is broadly categorized into three climatic zones (Wang'ati, 1996). The Saharo-Sahelian zone is extremely dry with an annual rainfall of 100 to 200 mm having 50% to 100% interannual variability. The Sahelo-Sudanian zone and Sudano-Guinean zones have annual rainfall of 200 to 400 mm and 400 to 800 mm, respectively, with 25% to 50% interannual rainfall variability.

Gommes and Petrassi (1994) and Jenkins et al. (2002) argued that since the early 1960s, regional rainfall patterns in West Africa have shifted mainly toward lower annual average rainfall.

The global circulation model (GCM)-based projections for climate change in Mali predict an extension, or perhaps continuation, of recent observed changes in the climate of West Africa. Figure 29.1 presents projected changes in temperature and precipitation for 2030 as different from the base temperature and precipitation of the 1960-1991 period. (GCM projections are provided for three time periods: 2010 to 2040, 2040 to 2070, and 2070 to 2100. In this study, we focus on the 2010-2040 time period.) Climate change projections made with two global circulation models — the Hadley Center coupled model (HadCM), and the Canadian coupled general circulation model (CGCM) — were obtained from the IPCC's Data Distribution Center. (The HadCM and CGCM were used

■ 25

-.m A 2 0

i 15

i *

A A 10

0 5

-,-,-,-0.0

Precipitation mm

Precipitation mm

CGCM = Canadian Coupled Model; HADCM = Hadley Coupled Model.

Figure 29.1 Projected changes in precipitation and temperature for Mali. CGCM = Canadian coupled general circulation model; HadCM = Hadley Center coupled model.

since they were employed in the U.S. national assessment, and we planned to use international market data arising in that assessment. We used the data from the IPCC's greenhouse gas integration scenario.) Projections indicate that Mali is likely to face a hotter, drier future. Twelve HadCM and eight CGCM grids cover Mali. Temperature increases are predicted in every grid cell. Five of the eight CGCM grids show increases in temperature of more than 2°C, as do four of the 12 HadCM cells. CGCM temperatures are generally higher than those in HadCM projections. On the precipitation side, 10 of the 12 HadCM cells show a decrease in precipitation, while all eight CGCM cells show a decrease.

0 0

Post a comment