Abstract: Based on daily sunshine duration, temperature, precipitation, wind speed and relative humidity at 7 weather stations in Bayingolin Mongol Autonumous Prefecture(Bazhou) of Xinjiang Uygur Autonomous Region from 1961 to 2013, temporal and spatial trends of annual and monthly as well as seasonal sunshine duration and its influence factors were analyzed by methods of a linear fitting, a 5 years sliding mean, an accumulated anomaly and a Mann-Kendall mutation test.The results indicate that annual average sunshine duration obviously decreases at the rate of 46.1 h per decade, so are the four seasonal values at the rates of 3.6 h per decade in spring, 16.3 h per decade in summer, 12.1 h per decade in autumn and 14.1 h per decade in winter respectively.The order of contribution to the change of annual sunshine duration from high to low in turn is summer, winter, autumn and spring.The maximum and minimum sunshine duration occur in August and December and account for 9.9% and 6.0% of the total annual sunshine duration respectively.The monthly sunshine duration are in a decreasing trend except in April.An abrupt change occurs in 1985 for annual sunshine duration, 1988 for summer sunshine duration, 1984 for autumn sunshine duration and 1985 for winter sunshine duration, while there is not the abrupt change for spring sunshine duration.Annual sunshine duration has a negative correlation with annual mean temperature, precipitation and relative humidity, while it has a positive correlation with wind speed.

Key words: Sunshine duration, Mutation test, Correlation analysis