Studies on net long-wave radiation on clear days in Hefei region (31.90N, I1 7.16E)

[ABSTRACT]Net long-wave radiation is an important component of radiation budget. The knowledge of induced factors (such as water vapor, aerosol) of radiation budget provides an opportunity for understanding the impact of environmental changes on climate. Utilizing the radiation data observed by pyrgeometer at definite times every day from 2003 to 2007 at SKYNET Hefei site in East China, the characteristic of net long-wave radiation over grassy land is discussed on 293 clear days. Meanwhile, based on these five years observations of integrated water vapor by microwave radiometer WVR-1100, variability of the atmospheric water vapor on sunny days has been statistically analyzed. And the aerosol optical property in the corresponding period is also obtained by an automated two wavelength (1064nm, 532nm) polarization (532nm) lidar. For the value of integrated water vapor, validation is given by a local radiosonde and good agreement is shown. As to the lidar dataset, we apply the Femald's method to derive the extinction coefficient. The profile of aerosol extinction coefficient is compared with anther lidar system PML and indicates great agreement. Then the AOD under the height of 3 km is calculated by layer-integrated extinction coefficient. This study mainly addresses the daily and seasonal variations of net long-wave radiation, integrated water vapor and AOD as well. We attempt to characterize the optical property of aerosol and the value of integrated water vapor and their effects on the net long-wave radiation over Hefei. The results show that some certain negative correlations are considered to occur between the latter two kinds of factors and the net long-wave radiation. And especially in summer the effects of water vapor and the aerosol on net long-wave radiation are very obvious. Large water vapor and aerosol loading lead to a very low net long-wave radiative effect.

https://opac.ll.chiba-u.jp/da/curator/106623/

https://opac.ll.chiba-u.jp/da/curator/106623/ceresIntlSympo-14-P065.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

14

65

68

2008-11-13

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」