How ECA’s Climate Has Changed and Is Likely to Change Further
MAP 2.3
Continued d. Change in summer (JJA) rainfall
Percent change −20 – −10
−10 – 0
0 – 10
10 – 20
0 – 10
10 – 20
e. Change in autumn (SON) rainfall
Percent change −20 – −10
−10 – 0
20 – 30
Source: Westphal 2008. Note: DJF = December, January, February. JJA = June, July, August. MAM = March, April, May. SON = September, October, November. All projections are based on the IPCC A1B climate scenario, and combine the results of twenty general circulation models. The projections indicate the difference between average precipitation in the period 2030–49, compared to the period 1980–99. Blank areas indicate where fewer than two-thirds of the models agree on the sign of the change.
ter (9 percent) and spring (5 percent) precipitation in Kazakhstan by mid-century and a decrease in precipitation in Southeastern Europe (–6 percent for the annual mean). The near-term picture of summer precipitation in Southeastern Europe is inconsistent across models, although end-of-century projections show consistent trends of decreasing precipitation (Parry et al. 2007). There is strong model disagreement for annual and seasonal precipitation on average for the Baltics, the Caucasus, Central Asia, and Central Europe. Finally, the models project that the interval between rainfall events will decrease in the north and east and increase in the south and west, with the greatest magnitude in Southeastern Europe (maximum consecutive dry days [CDD] increasing by 5 days) and Asian Russia (CDD decreases by 4 days in South Siberia). Runoff, a measure of water availability, is projected to decrease everywhere but Russia (map 2.4). The most dramatic decrease will likely occur in Southeastern Europe (–25 percent) and result in increased drought conditions (Milly, Dunne, and Vecchia 2005; Milly et al. 2008). The
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