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Drylands are one of the most sensitive areas to climate change. Many previous studies assessed the impact of 1.5 degrees C and 2 degrees C warming targets using transient warming scenarios by representative concentration pathways of CMIP5. Here we compared the climate changes over global drylands in transient and stabilized 1.5 degrees C and 2 degrees C warmer worlds using Community Earth System Model simulations. The projections indicate a warming of 2.3 degrees C (1.6 degrees C) over drylands could occur in a stabilized 2 degrees C (1.5 degrees C) warmer world by the end of this century. The warming in drier regions is higher and the hyper-arid areas would experience warming of 2.4 degrees C (1.8 degrees C). Comparing the 2 degrees C to 1.5 degrees C warming targets, the additional 0.5 degrees C warming will lead to similar to 1.0 degrees C warming in drylands of Eurasia and North America. Responding to the 2 degrees C warming, the increased precipitation (21.8-42.6mm/year) is not enough to offset the increased PET (88.3-101.7mm/year) over drylands, resulting in the drylands expansion, and the additional 0.5 degrees C global warming will aggravate the drought in drylands in southern North America and North Africa. Compared to the stabilized 2 degrees C warming target, controlling the global warming to within 1.5 degrees C will reduce the warming in drylands by 0.7 degrees C, and reduce the drylands expansion relative to 1961-1990 by similar to 44%. Compared to the stabilized warming scenarios, the temperature response and drylands area coverage increase are higher in the transient warming scenarios, but the difference of temperature caused by additional 0.5 degrees C global warming and the precipitation increase in drylands are lower.