Abstract:

Based on the simulations of 18 CMIP5 models under there RCP scenarios, this article investigates the changes of the mean temperature and precipitation as well as their extremes over Asia in the context of global warming targets of 1.5℃–4℃, and further compares their differences between the 1.5℃ and the 2℃ targets. The results show that relative to the preindustrial ear, the mean temperature over Asia will increase by 2.3℃, 3.0℃, 4.6℃ and 6.0℃ at the warming targets of 1.5℃, 2℃, 3℃ and 4℃, respectively, with stronger warming in the high latitudes than in the low latitudes. The corresponding enhancement in the mean precipitation over the entire Asian region is 4.4%、5.8%、10.2% and 13%, but there are significant regional differences. Meanwhile, an increase in warm extreme, a decrease in cold extreme, and an augment in the variability of the extreme precipitation amount are projected. Compared with the case under the 2℃ target, the mean temperature will cool more than 0.5℃–1℃ over Asia at the 1.5 target, and the mean precipitation will reduce 5%–20% over most of the Asian areas while increase by about 10–15% over West Asia and western South Asia. The extreme high temperature will appear uniformly lower in the Asian region, and the extreme low temperature will decrease significantly in the high latitudes of Asia. Increase in the extreme precipitation will weaken over most of Asia but enhance over West Asia. Under the 1.5℃ and 2℃ warming targets, the probability of the occurrence of hot weather, extremely hot weather and extremely strong precipitation will increase respectively by at least one times, 10% and 10% as compared to the reference period (1861–1900).

Key words: global climate model, CMIP5, warming target, climate extreme, climate change