城镇化发展背景下那曲地区气温变化的特征分析

根据西藏那曲气象站(NQ站)1955-2014年和其相邻野外站(BJ站)2001-2014年的气象观测资料,在那曲县城镇化发展背景下,对比分析了NQ站和BJ站气温变化的差异,从自然要素和人类活动要素两方面探讨了两站气温变化差异的原因.结果表明:近60 a NQ站气温呈上升趋势,且2001-2014年的气温上升率大于1955-2014年和1987-2000年的气温变化趋势;NQ站2001-2014年的平均气温、最高和最低气温的升温率,分别为0.52℃·(10a)-1,0.60℃·(10a)-1和0.67℃·(10a)-1;同时期BJ站的平均气温、最高和最低气温升温率,分别为0.76℃·(10a)-1、2.72℃·(10a)-1和0.32℃·(10a)-1.NQ站和BJ站的最高气温变化均主要与自然要素有关,NQ站的最高气温与日照(0.67)、降水(-0.62)、水汽压(-0.58)相关系数较高,BJ站的最高气温与日照(0.67)、NDVI(-0.63)、水汽压(-0.57)相关系数较高;NQ站的最低气温与人均GDP(0.53)、GDP(0.50)、总人口(0.47)相关系数较高,说明NQ站的最低气温变化主要是受人类活动因素的影响,人类活动对NQ站最低气温的热岛贡献率为52.2%;BJ站的最低气温与各因素相关系数均较小且接近,是在气候背景下的自然变化.

Feature analysis of the air temperature change in Nagqu Prefecture under the background of urbanization

According to the data obtained at Nagqu Meteorological Station(NQ,which is located inside Nagqu County)from 1955 to 2014 and at Nagqu Station of Plateau Climate and Environment(BJ)from 2001 to 2014, the differences of surface air temperature between NQ and BJ were calculated and analyzed under the back-ground of urbanization in Nagqu Prefecture. In addition,causes of the differences between the two stations were discussed from natural factors and human activities. The results show that the temperature at NQ Station had in-creased in the 60 years,with the increasing rate of 2001- 2014 higher than that of 1955- 2014 and 1987-2000. The mean,maximum and minimum temperatures at NQ Station from 2001 to 2014 increased with a rate of 0.52,0.60 and 0.67 ℃·(10a)-1,respectively;those at BJ Station from 2001 to 2014 increased with a rate of 0.76,2.72 and 0.32℃·(10a)-1,respectively. The contribution rate of human activities to the annual minimum temperature was 52.3%. There were good linear relationships between maximum temperature at NQ Station and natural factors such as sunshine hours(with a correlation coefficient of 0.67),precipitation(with a correlation coefficient of-0.62)and vapor pressure(with a correlation coefficient of-0.58). There were good positive cor-relations between minimum temperature at NQ Station and human factors such as per capita GDP(with a correla-tion coefficient of 0.53),GDP(with a correlation coefficient of 0.50)and total population(with a correlation co-efficient of 0.47). At the same time,there were higher correlation coefficients between the maximum tempera-ture at BJ Station and sunshine hours(with a correlation coefficient of 0.67),NDVI(with a correlation coeffi-cient of-0.63)and vapor pressure(with a correlation coefficient of-0.57). The minimum temperature at BJ Sta-tion did not show a specific correlation with nature and human factors,which was only a natural change under the background of climate change in Nagqu Prefecture.