Column water vapor retrievals from skyradiometer (POM- 02) 940nm channel data.

[ABSTRACT]Skyradiometer (POM-02, Prede Co., ldt.) is used to retrieve aerosol optical properties and to estimate the radiative effect of aerosol properties on the surface solar irradiance. The skyradiometer (POM-02) has a 940nm channel in the water vapour absorption band. This channel data is not fully utilized until now. The column water vapour is one of the important factors to determine the surface radiation budget and in addition when we use the near infrared channels, 1225, 1627, 2200nm, the transmittances by water vapour in these channels are necessary. In this study, the 940nm channel was calibrated by the Langley method, which is taken into account of gas absorption. The relation between column water vapour is determined using the simulation data; McClatchey’s (1972) five atmospheric models, U.S. standard atmosphere 1962, and four modified McClatchey’s atmospheric models were used to calculate the transmittance at 10 different times in order to simulate a large range of path length. Once the transmittance is obtained, we can retrieve column water vapour using this relation. This method was applied to the data at Tsukuba, Japan in 2010 and the comparison between column water vapours from POM-02 and GPS was made. The results show that bias error is 0.09 (g/cm2), root means square error is 0.179(g/cm2), and correlation coefficient is 0.966. The coefficients of linear regression line (POM-02=C1*GPS+C2) between them are C1=0.957 and C2=0.169.

https://opac.ll.chiba-u.jp/da/curator/107443/

https://opac.ll.chiba-u.jp/da/curator/107443/ceresIntlSympo-19-P012.pdf

Chiba University. Center for Environmental Remote Sensing

千葉大学環境リモートセンシング研究センター

会議発表用資料

Proceedings of the CEReS international symposium = CEReS国際シンポジウム資料集

19

12

12

2013-07-04

publisher

環境リモートセンシング研究センター「CEReSシンポジウム資料集」