Abstract: Based on the daily temperature data of sixteen meteorological stations in ürümqi City and the Changji Hui national autonomous prefecture of Xinjiang (the ürümqi-Changji region) during 1961-2010, the fundamental spatial and temporal change characteristics of the annual accumulated temperature of ≥10℃, July (the warmest month in a year) mean temperature and frost-free period were analyzed by using the linear regression method, the t-test and the three-dimensional and quadratic trend surface simulation and the inverse-distance squared weighting residual error revising based on GIS. The cotton-planting climate zoning for the ürümqi-Changji region in 1961-2003 and 2004-2010 were completed with the climate indicators of cotton zoning. Possible changes of climate zoning for cotton planting relative to that in 1961-2010 were projected for the future when annual mean temperature increases 1℃, 2℃, 3℃ and 4℃, respectively. The main results are as follows: the agro-climatic heat resource in 1961-2010 was obviously different from areas of the ürümqi-Changji region; generally, the annual accumulated temperature of ≥10℃, July mean temperature and frost-free period were higher/longer in plain areas than in mountainous areas. The three indicators showed an increasing trend at the rates of 52.3℃•d/10a、0.1℃/10a and 3.3 d/10a in 1961-2010, and had an abrupt increase, rise and extension in 1995, 2004 and 1987, respectively. Under the joint effects of the above-mentioned climate factors, the area suitable for cotton growing after 2004 had a substantial expansion relative to that before 2004, but the areas secondly suitable, risk and unsuitable for cotton growing reduced to different extent. The global warming in future will significantly affect the cotton zoning in the ürümqi-Changji region. Overall, under the premise of other conditions remaining invariant, when the annual mean temperature increases by 1℃ relative to that of 1961-2010, the area suitable for cotton growing will increase 6600 km², and the areas secondly suitable and unsuitable for cotton growing will reduce 2100 km² and 4700 km², respectively, but change in the area risk for cotton growing will be very small.

Key words: global warming, heat resource, cotton-plating zoning, Ü, rü, mqi-Changji region