1.2.2. Rainfall
By 2020, all three scenarios project increases in total annual rainfall of 1.4 to 1.8% for
northern climate zones and 0.3 to 0.7% for southern climate zones over 1980-1999
levels.By 2050, rainfall will have increased by 3.8 to 4.1% in northern climate zones, but only
by 0.7%-1.7% in the South Central Coast and further south.
By 2100, annual rainfall in northern climate zones is projected to increase by 4.8 to 5.2%
in the low scenario, 7.3 to 7.9% in the medium scenario and 9.3% to 10.1% in the high
scenario. From the South Central Coast southwards, the increase will be smaller,
averaging 1.0 to 3.2% in the low and medium scenarios and 1.8 to 4.1% in the high
scenario (Table 1).
Rainfall is projected to decrease during the dry season in almost every region, most
markedly in the south. In the rainy season, rainfall is likely to increase in all regions.
Overall, total annual rainfall is set to increase throughout the country.