热带地理 ›› 2015, Vol. 35 ›› Issue (6): 852-859.doi: 10.13284/j.cnki.rddl.002763

• 论文 • 上一篇    下一篇

考虑多大气参数不确定性的地面太阳短波辐射估算误差数学期望

饶俊峰,张显峰   

  1. (北京大学 遥感与地理信息系统研究所,北京 100871)
  • 出版日期:2015-11-05 发布日期:2015-11-05
  • 通讯作者: 张显峰(1967-),男,四川人,副教授,博士,主要从事生态环境遥感研究,(E-mail)xfzhang@pku.edu.cn。
  • 作者简介:饶俊峰(1990-),男,福建人,硕士研究生,主要从事生态环境遥感研究,(E-mail)raopku@qq.com
  • 基金资助:

    国家科技支撑计划项目(2012BAH27B03);国家自然科学基金(41071257)

Mathematical Expectation of the Surface Solar Irradiance Estimation Error under the Combined Uncertainty Impact of Multi Remotely Sensed Atmospheric Parameters in Hong Kong

RAO Junfeng,ZHANG Xianfeng   

  1. (Institute of Remote Sensing and Geographical Information System,Peking University,Beijing 100871,China)
  • Online:2015-11-05 Published:2015-11-05

摘要:

以香港地面站观测的AOD与WVC数据为参照,首先分析了MISR/AOD和MODIS/WVC产品的不确定性描述方法,然后在考虑二者联合不确定性的影响下,推导了辐射传输方程法估算地面太阳短波辐射的相对误差分布函数。通过统计2005―2013年香港MISR/AOD和MODIS/WVC反演值的分布情况,得出两者的联合概率密度函数,然后将AOD和WVC的联合概率密度函数作为权重函数与相对误差分布函数积分,得到对辐射传输方程法估算地面太阳短波辐射的相对误差数学期望。结果表明,夏季在太阳天顶角为0°时,使用MISR/AOD和MODIS/WVC产品估算地面太阳短波辐射的相对误差期望为3.17%,并且有90%的把握使估算结果相对误差<3.53%;不同季节不同太阳天顶角下、不同置信水平下,地面太阳短波辐射估算的相对误差大小,可为不同应用研究提供基础数据,为评估亚热带地面太阳短波辐射估算结果是否符合应用需求提供依据。

关键词: 太阳短波辐射, 气溶胶光学厚度, 大气可降水量, 不确定性, 数学期望

Abstract:

The radiative transfer equation simulation method is an accurate and effective way to estimate the surface solar irradiance, however, as the input data, the satellite remotely sensed atmospheric parameters have some uncertainty because of the retrieval algorithm and the sensors. The atmospheric parameters uncertainty effect brings error to the estimation of the surface solar shortwave irradiance using the radiative transfer equation method which takes the satellite remotely-sensed atmospheric parameters as input data. It is obviously more creditable to consider the combined uncertainty effect of multi atmospheric parameters than to take single atmospheric parameter uncertainty effect into consideration alone. The Multi-angle Imaging SpectroRadiometer (MISR) Aerosol optical depth (AOD) product and Moderate Resolution Imaging Spectroradiometer (MODIS) water vapor column product (WVC) uncertainty calculation formulas are derived from comparing satellite remote sensing products with the surface measured data in Hong Kong. By analyzing MISR/AOD and MODIS/WVC product values distribution in Hong Kong in the period from 2005 to 2013, the combined probability density distribution function of MISR/AOD and MODIS/WVC is obtained. Using the combined probability density distribution function as a weight function, which is multiplied with the relative error distribution function of the estimation of surface solar shortwave irradiance, the mathematical expectation of the surface solar irradiance calculation relative error under the multi remotely sensed atmospheric parameters’ combined uncertainty impact is worked out. The conclusion shows that when the solar zenith angle is 0° in the summer, the relative error mathematical expectation of the surface solar irradiance estimation is 3.17%, and with a 90% confidence that the relative error mathematical expectation will be lower than 3.53%. Besides the situation that the solar zenith angle is 0° in the summer, the relative error mathematical expectations under various solar zenith angle in different seasons are also obtained which provide the scientists and engineers a look up table for checking that if the accuracy of the surface solar shortwave irradiance estimation results satisfy their application requirements, especially for the application in the subtropical climate area.

Key words: solar shortwave irradiance, AOD, WVC, uncertainty, mathematical expectation