Abstract: Based on the output of CMIP5 coupling models under RCP2.6, RCP4.5 and RCP8.5 scenarios, the time with a 2℃ global warming was detected, taking 1890-1900 as a baseline climatology. The mean climate change and extreme climate events over the Qinghai-Tibetan Plateau at that time were compared with the baseline climatology. The results show that 2℃ global warming will appear respectively in 2063, 2040 and 2036 under the RCP2.6, RCP4.5, RCP8.5 scenarios, and the temperature of the Qinghai-Tibetan Plateau will increase 2.99℃, 3.22℃ and 3.28℃ respectively, which are higher than 2℃ of global warming level. The annual precipitation will also increase, and the anomaly percentage is 8.35%, 7.16% and 7.63% respectively. Affected by the temperature and precipitation increasing, the frost days and frozen days will reduce; the days of warm night and warm day will increase; the moderate rain days, strong precipitation, and precipitation intensity will increase; the days of continuous drought will decrease under RCP4.5 scenario. Chaidam Basin is a sensitive area to climate change in the Qinghai-Tibetan Plateau according to the change results of mean climate and extreme climate events.

Key words: 2℃ global warming, the Qinghai-Tibetan Plateau, mean climate, extreme climate events