不同地表两种观测尺度红外辐射温度的对比分析

Comparison of Infrared Radiative Temperatures from Two Scales on Different Land Surfaces

针对地表红外辐射温度观测时，红外辐射仪在地面均匀分布的点上尺度观测温度的平均值代替面上尺度观测值存在的误差问题，在晴天太阳直接辐射下使用红外热像仪、红外辐射仪从10：00～16：30同步连续观测草地、裸土、沥青路面、水泥坪的辐射温度并比较。结果表明，辐射仪地表点上尺度观测温度的平均值代替热像仪面上尺度观测温度，较适用于沥青路面和水泥坪，适用于裸土，但不适用于草地等植被覆盖地表。两种尺度观测温度的偏离，以沥青路面和水泥坪最小，而草地最大，中午地表温度较高时这种偏离比其他时刻更大；12：30偏离值在沥青路面和水泥坪低于0．5℃，在裸土不高于1．0℃，而在草地达到3．6℃。

Infrared radiative temperatures （IRT） land surface of could be measured with infrared radiometer on point scale and infrared thermal camera on area scale. However, it results in errors when average IRT on point scale is used to replace IRT on area scale. Therefore,IRTs on the lawn,bare soil,asphalt road and concrete plaza are measured from 10：00 to 16：30 using both radiometer and thermal camera in clear and sunny days ,and are compared. Results show that it＇s more suitable for both asphalt road and concrete plaza,suitable for bare soil,but not for lawn as average IRT measured with radiometer replaces IRT with thermal camera. The errors between IRTs on the two scales are minimum on asphalt road and concrete plaza,maximum on lawn,and are much greater with high IRT at noon than that at other moments. The errors are less than 0.5 ℃ on asphalt road and concrete plaza,not greater than 1.0 ℃ on bare soil and reach 3.6 ℃ on lawn at 12：30.