水汽是地球大气的重要成分,对大气中传输的红外辐射造成严重的衰减,影响光电设备的探测性能。利用 改进的Langley法对太阳光度计940 nm探测通道进行定标,根据水汽吸收透过率与水汽总量的关系,应用 太阳辐射计的观测资料反演出合肥和新疆两地的大气水汽总量,并与同时期地基微波辐射计在以上两 地区的探测值相比较。结果表明:地基微波辐射计观测的水汽总量日变化趋势和太阳光度计具有 较好的一致性,二者观测的日均水汽总量变化趋势非常吻合,相对偏差小于5.1%。

Water vapor is an important component of terrestrial atmosphere, which attenuates infrared radiance in the atmosphere and affects optical-electron engineering capability. The 940 nm channel of sun-photometer was calibrated by modified Langley method. According to the relationship between atmospheric transmittance and water vapor amount, the precipitable water vapor(PWV) was measured with ground-based microwave radiometer in Hefei, Anhui and Kashi, Xinjiang regions. The results showed that the PWV retrieved by these methods agrees with each other, the relative percent difference in the retrievals is less than 5.1%. The daily PWV retrievaled by microwave radiometer agreed well with the sun-photometer.