Abstract:
Based on the historical data recorded at the meteorological stations of Lhasa City,Meldro Gungkar County and Nyemo County,together with those collected at 8 recently established automatic meteorological stations in Lhasa city,the variations and trends of the urban heat island (UHI) effect in Lhasa City are analyzed,and the possible impact factors on UHI effect in Lhasa City are discussed.It shows that the UHI effect in Lhasa City has a significant increasing trend from 1978 to 2011,with an average value of 0.24℃ per decade.On average,the highest intensity of UHI effect appears in winter (2.0℃),followed by that in spring (1.8℃),autumn (1.7℃),and summer (1.6℃).It appears that the central of high temperature is mainly at the center of the city,and the temperature declines from high-level area to its flanks.Temperatures in rural areas are relatively lower than that in urban areas with a mean difference of 0.9℃.Moreover,nocturnal heat island intensity was significantly higher than that during the day.With growing urbanization,a large change of surface land conditions,a growing number of city buildings,the surge of human activities and energy consumption,are responsible of resulting in growing UHI effect in the Lhasa City.