| 应用于O2-A波段云检测的阈值选取方法 |
| |
| 引用本文： | 江新华,王先华,叶函函,卜婷婷,桑浩.应用于O2-A波段云检测的阈值选取方法[J].武汉大学学报(信息科学版),2017,42(2):202-207. |
| |
| 作者姓名： | 江新华 王先华 叶函函 卜婷婷 桑浩 |
| |
| 作者单位： | 1.中国科学院安徽光学与精密机械研究所, 安徽 合肥, 230031 |
| |
| 基金项目： | 国家自然科学基金No. 41175037 |
| |
| 摘 要： | 云污染直接决定了卫星数据用于反演的可行性，云检测是温室气体反演流程中的必要环节，阈值的选取决定了在O2-A波段利用阈值法对卫星数据进行云检测的效果，如何获取最优阈值成为关键，目前的阈值选取大多数是经验法，缺乏系统考虑。提出了一种半经验阈值选取方法，根据晴空涵盖率和误判率构建优选函数，通过求取优选函数的极值实现了最优阈值的选取。利用GOSAT卫星数据进行算法验证的结果显示，相比于传统的经验统计法，该方法所选取的阈值应用于O2-A波段云检测时，云判定的准确率提高近10%。
|
| 关 键 词： | 温室气体 云检测 O2-A波段 阈值 |
| 收稿时间： | 2014-10-22 |
Threshold Selecting Method of Cloud Detection Applied to O2-A Band |
| |
| Affiliation: | 1.Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031, China2.Key Laboratory of Optical Calibration and Characterization of Chinese Academy of Science, Hefei 230031, China |
| |
| Abstract: | Cloud cover status determines whether satellite data can be used for retrieving or not. Cloud screening is essential in data processing flow of greenhouse gases retrieval. The threshold, whether appropriate or not, determines the accuracy of cloud detection in O2-A band via threshold method, methodology of how to obtain optimal threshold becomes a key-point requirement. Thresholds are selected based on empirical statistics that hence lack of systematism in most cases. A semi-empirical algorithm of threshold selection has been proposed, the algorithm construct a function by combining clear-sky contain ratio and false determinant ratio, then selecting the optimal threshold through seeking the maximum of this function. Finally, the algorithm was validated by GOSAT observation data and the result shows that, comparing with traditional statistical method, threshold determined by this algorithm increasing the cloud detection accuracy near upon 10 percent when applying it to O2-A band cloud detection. |
| |
| Keywords: | |
| 本文献已被 CNKI 等数据库收录！ |
| 点击此处可从《武汉大学学报(信息科学版)》浏览原始摘要信息 |
|
点击此处可从《武汉大学学报(信息科学版)》下载全文 |
|
