现有的辐射传输模型仅考虑气溶胶影响下的大气透过率,在能见度低于5km时,会给大气透过率计算带来较大的误差。本文综合考虑影响大气透过率的气溶胶和水汽因素,并利用中光谱分辨率MOD IS(moderateresolution im aging spectrorad iom eter)数据,在特征参数的空间及时间尺度变化均比较大时,对大气透过率进行了定量反演,并进一步建立了整层大气透过率与行星反照率的关系模型,为近地层大气能见度的遥感监测提供了方法。
Based on the atmospheric horizontal visibility data from forty-seven observational stations along the eastern coast of China near the Taiwan Strait and simultaneous NOAA/AVHRR multichannel satellite data during January 2001 to December 2002, the spectral characters associated with visibility were investigated. Successful retrieval of visibility from multichannel NOAA/AVHRR data was performed using the principal component regression (PCR) method. A sample of retrieved visibility distribution was discussed with a sea fog process. The correlation coefficient between the observed and retrieved visibility was about 0.82, which is far higher than the 99.9% confidence level by statistical test. The rate of successful retrieval is 94.98% of the 458 cases during 2001 2002. The error distribution showed that high visibilities were usually under-estimated and low visibilities were over-estimated and the relative error between the observed and retrieved visibilities was about 21.4%.