中国低纬度地区水汽转换系数分析研究

Research on the Water Vapor Conversion Coefficient in the Low-Latitude Region of China

大气水汽转换系数K是利用对流层天顶湿延迟反演大气可降水量的关键参数,而大气水汽转换系数K的精度又要取决于加权平均温度Tm的精度。据此,利用中国低纬度地区8个探空站的相关数据,在Bevis公式的基础上加入了测站纬度和测站高程的影响因素,建立了一种与测站地面温度、测站纬度和测站高程有关的新的加权平均温度Tm模型,相比于Bevis模型,其在中国低纬度地区的精度提高了约29.7%,更适用于中国低纬度地区加权平均温度Tm的计算。

The atmospheric water vapor conversion coefficient(K)is the key parameter for estimating atmospheric perceptible water by using the Zenith Hydrostatic Delay.The accuracy of the atmospheric water vapor conversion coefficient K depends on the accuracy of the weighted mean temperature Tm.Based on the Bevis formula,we add the influence factors of latitude and elevation by using the data of eight sounding stations in low-latitude area.A new model is established to describe the relationship between ground temperature,latitude,elevation and the weighted mean temperature.Compared with the Bevis model,the accuracy of the new model in China improves 29.7%,which is more suitable for the calculation of the weighted mean temperature in the low-latitude region of China.