| 引用本文: | 陈军,付军,孙记红.几何校正对暗像元算法及离水辐亮度反演精度的影响:以太湖为例.湖泊科学,2011,23(1):89-94. DOI:10.18307/2011.0114 |
| CHEN Jun,FU Jun,SUN Jihong.Influences of geometric correction on the accuracy of dark pixel atmospheric correction algorithm and water leaving irradiance retrieval:a case study of Lake Taihu. J. Lake Sci.2011,23(1):89-94. DOI:10.18307/2011.0114 |
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| 摘要: |
| 几何校正将引起几何校正前后像元的像素值发生变化, 进而导致暗像元的辐亮度在几何校正前后存在偏差.本文以太湖为研究水区, 以2003年10月28日的Landsat/TM影像、2008年7月24日的CBERS影像和2009年4月25日的HJ-1B影像作为数据基础, 研究与探讨了几何校正对暗像元大气校正算法以及离水辐亮度反演精度的影响.通过本文的研究可知, 几何校正将引起Landsat数据、CBERS数据和HJ-lB数据的暗像元辐亮度存在0.2, 0.47和0.882W/(m2·sr·μm)的绝对偏差;对于上述三景数据, 几何校正将引起3.28%-9.81%的基于暗像元方法的气溶胶光学厚度估算偏差;几何校正对基于Landsat/TM影像数据和CBERS影像数据的离水辐亮度反演精度影响相对较小, 其误差主要为0-6%, 对基于HJ-1B卫星数据的离水辐亮度反演精度的影响相对较大, 其误差主要为0-15%, 局部区域可达40%以上.因此, 大气校正必须在几何校正之前进行处理。 |
| 关键词: 几何校正 大气校正 暗像元 离水辐亮度 太湖 |
| DOI：10.18307/2011.0114 |
| 分类号: |
| 基金项目:国家科技支撑计划十一五项目(2008BAC34B03)和中国海陆地质地球物理系列图项目(GZH200900504)联合资助 |
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| Influences of geometric correction on the accuracy of dark pixel atmospheric correction algorithm and water leaving irradiance retrieval:a case study of Lake Taihu |
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CHEN Jun1,2, FU Jun1,2, SUN Jihong1,2
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1.The Key Laboratory of Marine Hydrocarbon Resources and Environmental Geology, Qingdao 266071, P.R.China;2.Qingdao Institute of Marine Geology, Qingdao 266071, P.R.China
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| Abstract: |
| The pixel values would be different before and behind the geometric correction, which would lead to the different irradiance of dark pixel before and behind the geometric correction.Regarding the Lake Taihu as the study area and using the Landsat/TM, CBERS and HJ-1B satellite imageries, data collected at October 28, 2003, July 24, 2008 and April 25, 2009, respectively, as the data foundation, the paper researched and discussed the influences of geometric correction on the accuracy of dark pixel atmospheric correction algorithm and water leaving irradiance retrieval production.The results showed that the geometric correction would caused to 0.2, 0.47, 0.882 W/(m2·sr·μm) irradiance absolute deviations of dark pixel for Landsat/TM, CBERS and HJ-1B satellite imageries, respectively.There were 3.28%-9.81% relative biases for aerosol optical thickness estimated from the dark pixel algorithm.The influences of geometric correction would be relatively smaller on the Landsat/TM and CBERS imageries (relative bias mainly about 0 -6%), and relatively larger on the HJ-1B satellite imagery(relative bias mainly about 0-15%, and some regions up to 40%).As a result, it was well known that the atmospheric correction must be calculated before the geometric correction. |
| Key words: Geometric correction atmospheric correction dark pixel water leaving irradiance Lake Taihu |
