石家庄市区域自动气象站气温数据适用性分析

Applicability analysis of air temperature data from regional automatic weather stations in Shijiazhuang

利用2009—2015年石家庄地区17个国家级自动气象站和61个两要素区域自动气象站的逐时气温、逐日最高气温及逐日最低气温观测资料,对比分析了石家庄市国家站和区域站逐时与逐日气温空间分布特征的相似性及差异性。结果表明:探测环境差异对日最低气温观测值的影响较大,对日最高气温观测值的影响较小。石家庄市不同区域气温冬季差异最大,夏季差异最小,春秋季居中;太阳辐射可以减小区域之间气温的差异,日出后不同区域的气温差异快速缩小,辐射最强时气温差异最小,日落后不同区域气温差异达最大,直至日出前不同区域的气温差异变化微弱,始终保持较高差值。石家庄市西北部山区气温较低,东部平原地区气温较高,石家庄城区气温最高。选取不同探测环境的气象站统计某区域平均气温时,对日平均最高气温统计值的影响较小,对日平均最低气温统计值的影响较大;23时至翌日上午10时,国家级自动气象站气温差异的季节变化特征可以代表全区气温差异的季节变化,其他时刻代表性较差,18—20时气温差异的代表性最差;冬季夜间石家庄市主城区相对周边地区城市热岛最明显,夏季山区相对城区最高气温更低,冬春季白天城区相对乡镇存在明显的冷岛现象。

The similarities and differences of spatial distributions of hourly and daily air temperature observed at na- tional and regional weather stations were crossly compared, which include observational data of hourly air temperature and daily maximum and minimum air temperature from 17 national weather stations and 61 regional weather stations in Shijiazhuang region from 2009 to 2015. The results show that observational environment has larger in- fluence on daily maximum air temperature and smaller effect on daily minimum air temperature. The differences of air temperature among different regions in Shijiazhuang are the largest in winter, the smallest in summer, and moderate in spring and autumn. Effect of solar radiation can reduce the temperature difference between different re- gions. Temperature difference quickly reduces after sunrise and reaches the smallest as radiation is the strongest. The largest temperature differences occur after sunset and remain a high level until sunrise. The values of air tem-perature are low in the northwestern mountainous region of Shijiazhuang and are higher in the eastern plain region, and highest in the urban region. The usage of different weather stations under different observational environment has more effects on the statistical value of daily minimum air temperature than that on daily maximum air tempera- ture. The seasonal variation of temperature differences observed at national stations from 23 ： 00 to the next day 10.00 can represent the temperature variation in the entire region, however, such representativeness is worse at oth- er hours and worst from 18：00 to 20：00. The urban heat island effect appears more obvious in the main urban re- gion than in the surrounding area of Shijiazhuang during nighttime in winter, and the maximum air temperature in the mountainous region is smaller than that in the urban region in summer. The urban cold island effect is most obvious in county city than in villages and towns at daytime in winter and spring.