基于气象数据和遥感影像的太白山气温直减率

Temperature Lapse Rates in the Taibai Mountain Based on Meteorological Data and Remote Sensing Image

基于太白山内2013—2014年气象站点实测数据和DEM分析太白山南北坡不同时间尺度的气温直减率,并利用辐射传输方程法针对Landsat 8影像数据反演地表温度场,通过窗口差分法推导太白山气温直减率场及其特征。研究表明:1实测法计算太白山年均气温直减率北坡为0.515℃/(100 m),南坡为0.505℃/(100 m);10月直减率北坡为0.505℃/(100 m),南坡为0.480℃/(100 m);春、夏季气温直减率较大,北坡大于南坡,而冬季较小,北坡小于南坡。2采用辐射传输方程法针对Landsat 8 TIRS 10反演地表温度具有较高置信度,获取10月北坡气温直减率为0.611℃/(100 m),南坡为0.502℃/(100 m)。3气温直减率在山脊和山谷附近表现出高直减率条带;海拔对太白山气温直减率的影响高于坡向,高、中、低海拔区气温直减率分别为0.913℃/(100 m)、0.471℃/(100m)、0.755℃/(100 m);坡向对气温直减率分布的影响表现为随阳坡至阴坡而逐渐变大,依次为0.515℃/(100m)、0.541℃/(100 m)、0.617℃/(100 m)。

Based on DEM and records of daily average temperature in the period of 2013 to 2014 from 11 meteorological stations in the Mt. Taibai,Western China,we calculated the temperature lapse rate at different time scales on the southern and northern slopes of the Mt. Taibai,including monthly,seasonally and annually. Also,we obtained the temperature lapse rate at a grid-cell level and analyzed its distribution characteristics by a custom neighborhoods difference operation,since land surface temperature was retrieved from Landsat 8 images in Mt. Taibai by the method of radioactive transfer equation. Results showed that 1） Average annual temperature lapse rate calculated by measured data on the northern slope is 0. 515 ℃ /（ 100 m）,while on the southern slope is 0. 505 ℃ /（ 100 m）.The temperature lapse rate in spring and summer,both of which on the northern slope are larger than that on the southern slope on the contrary to winter,is sharper than in autumn and winter. 2） The radioactive transfer equation method for Landsat 8 TIRS band 10 to retrieve land surface temperature have a high confidence and get the temperature lapse rate for 0. 611 ℃ /（ 100 m） on the northern slope in October,0. 502 ℃ /（ 100 m） on the southern slope. 3） The temperature lapse rate shows a high value strip in the vicinity of the ridge and valley. Effects of altitude on the vertical variation of air temperature is more significant than that of aspect. Temperature lapse rate is 0.91 ℃ /（ 100 m） in the high altitude areas,0. 47 ℃ /（ 100 m） in the middle altitude zones,and 0. 75 ℃ /（ 100 m）in the low altitude areas. Temperature lapse rate effected by aspect gradually becomes stronger from shady to sunny slope.