11.4.3 Climate Projections
The temperature projections for the 21st century based on the MMD-A1B models (Figure 11.8 and Table 11.1) represent a strong warming over the 21st century. Warming is similar to the global mean warming in Southeast Asia (mean warming between 1980 to 1999 and 2080 to 2099 of 2.5°C). Warming greater than the global mean is projected for South Asia (3.3°C) and East Asia (3.3°C), and much more than the global mean in the continental interior of Asia (3.7°C in central Asia, 3.8°C in Tibet and 4.3°C in northern Asia). In four out of the six regions, the largest warming occurs in DJF, but in central Asia, the maximum occurs in JJA. In Southeast Asia, the warming is nearly the same throughout the year. Model-to-model variation in projected warming is typically about three-quarters of the mean warming (e.g., 2.0°C to 4.7°C for annual mean warming in South Asia). The 5 to 95% ranges based on Tebaldi et al. (2004a) suggest a slightly smaller uncertainty than the full range of the model results (Supplementary Material Table S11.2). Because the projected warming is large compared to the interannual temperature variability, a large majority of individual years and seasons in the late 21st century are likely to be extremely warm by present standards (Table 11.1). The projections of changes in mean temperature and, where available, temperature extremes, are discussed below in more detail for individual Asian regions.
Figure 11.8. Temperature anomalies with respect to 1901 to 1950 for six Asian land regions for 1906 to 2005 (black line) and as simulated (red envelope) by MMD models incorporating known forcings; and as projected for 2001 to 2100 by MMD models for the A1B scenario (orange envelope). The bars at the end of the orange envelope represent the range of projected changes for 2091 to 2100 for the B1 scenario (blue), the A1B scenario (orange) and the A2 scenario (red). The black line is dashed where observations are present for less than 50% of the area in the decade concerned. More details on the construction of these figures are given in Box 11.1 and Section 11.1.2.