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Estimating surface evapotranspiration using combined MODIS and CBERS-02.data

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science china(Technological {2.) 2005年第S2期48卷 145-160页

作者： XIN Xiaozhou1,2. liU Qinhuo1, TANG Yong1,3, tian guoliang1, gu xingfa1, li {2.,2. ZHENG Hongsheng4.& CHEN Jiayi4.1. state key laboratory of remote Sensing science, institute of remote Sensing applications, Chinese {12. of sciences, beijing 100101, china 2. Research Center for remote Sensing and GIS, Department of Geography, beijing normal {24., beijing 100875, china 3. Graduate {24. of Chinese {12. of sciences, beijing 100039, china 4. Department of Atmospheric Physics, Peking {24., beijing 100871, china 1. state key {2. of remote Sensing {4. Institute of Remote Sensing Applications Chinese Academy of Sciences 100101 Beijing China2. Research Center for Remote Sensing and GIS Department of Geography Beijing Normal University 100875 Beijing China3. Graduate University of Chinese Academy of Sciences 100039 Beijing China4. Department of Atmospheric Physics Peking University 100871 Beijing China

Spatial scale error is one of the most serious problems in the estimates of land surface heat fluxes of sensible and latent from satellite-borne data such as MODIS 1km resolution reflectance and emissive data. One of the feasible and economic ways to decrease the spatial scale error is to use high resolution land use class data together with the MODIS data. CBERS-02.data were used to produce land use class of Baiyangdian area, Hebei Province, china in the autumn of 2.04. The area ratio of each class in MODIS pixel was calculated, and used to derive the heat fluxes of the mixed pixel. The results showed that the estimated heat fluxes of soil, sensible and latent have been changed remarkably after using the high resolution land class data. It could be concluded from the comparison between simulated and ground-measured fluxes as well as the theoretical analysis that high resolution land class data are useful to diminishing the scale error of heat fluxes estimated from low resolution satellite data.

关键词： surface evapotranspiration spatial scale error MODIS CBERS land class.

Radiometric cross-calibration of the CBERS-02.CCD camera with the TERRA MODIS

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science china(Technological {2.) 2005年第S2期48卷 44-60页

作者： li Xiaoying1,2.3, gu xingfa1,3,4. MIN Xiangjun5, YU Tao1,3, FU Qiaoyan5, ZHANG Yong1,2.3 & li xiaowen1,3 1. state key laboratory of remote Sensing science, jointly sponsored by the institute of remote Sensing applications of Chinese academy of sciences and beijing normal university, beijing 100101, china 2. Graduate university of Chinese academy of sciences, beijing 100039, china 3. The Center for National Spaceborne Demonstration, beijing 100101, china 4. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84.14.Avignon, France 5. china Center for Resource Satellite Data and Application, beijing 100830, china 1. state key {2. of remote Sensing {4. Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University 100101 Beijing China 2. Graduate university of Chinese academy of {2. 100039 Beijing China 3. The Center for National Spaceborne Demonstration 100101 Beijing China 4. Institut National de la Recherche Agronomique Climat Sol Environnement 84914 Avignon France 5. china Center for Resource Satellite Data and Application 100830 Beijing China

For the application of the CCD camera, the most important payload on CBERS-02. the key is to provide long-term stable radiometric calibration coefficients. Although the vicarious calibration had been proved successful, it had its limitations such as test site requirement and unsuitable for historical data. Cross-calibration is one of the alternative methods, but it needs synchro surface spectrum to achieve spectral band matching factors. Our effort is to probe the influences on these factors. Simulations with a lot of surface spectrum showed that the factors changed with the viewing geometry, atmospheric condition and surface targets. However, simulating with the same viewing geometry and atmospheric condition, the spectral band matching factors of the same or similar surface targets’ spectrum acquired from different dates and different places would like to be consistent to each other within 1%―5%. Thus, the synchro measurement data can be substituted by the same or similar target from other source. Based on this method, using the MODIS as the reference, the cross-calibration was performed for CCD camera. The research demonstrated that the traditional method with single calibration site was inappropriate for CCD camera, since the offsets for its four spectral bands were not zeros. With four calibration sites, these offsets were obtained. And the camera was detected to degrade with dates based on four times of cross-calibrations.

关键词： CBERS-02 CCD camera cross-calibration the spectral band matching factors.

Absolute radiometric calibration of CBERS-02.IRMSS thermal band

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science china(Technological {2.) 2005年第S2期48卷 72-90页

作者： ZHANG Yong1,2.3, gu xingfa1,3,4. YU Tao1,3, ZHANG Yuxiang5, CHEN liangfu1,3, li Xiaoying1,2.3, li xiaowen1,3 & HE liming6 1. state key laboratory of remote Sensing science, jointly {14. by the institute of remote Sensing applications of Chinese academy of sciences and beijing normal university, beijing 100101,{24. 2. Graduate university of Chinese academy of sciences, beijing 100039,{24. 3. The Center for National Spaceborne Demonstration, beijing 100101,{24. 4. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84.14.Avignon, France 5. National Satellite Meteorological Center, beijing 100081,{24. 6. state Environmental Protection Administration, beijing 100029,{24. Chinese Acad Sci Inst Remote Sensing Applicat State Key Lab Remote Sensing Sci Beijing 100101 Peoples R China beijing normal Univ State Key Lab Remote Sensing Sci Beijing 100101 Peoples R China Chinese Acad Sci Grad Univ Beijing 100039 Peoples R China Ctr Natl Spaceborne Demonstrat Beijing 100101 Peoples R China INRA F-84914 Avignon France Natl Satellite Meteorol Ctr Beijing 100081 Peoples R China state Environm Protect Adm Beijing 100029 Peoples R China

Based on the laboratory calibration before launch of CBERS-02.IRMSS thermal infrared channel, the onboard blackbody calibration, the radiometric cross- calibration against TERRA MODIS corresponding channel and the in-flight field calibration at Lake Qinghai: water surface radiometric calibration test site of china on Aug. 17, 2.04.are carried out in this research. When making onboard blackbody calibration of CBERS-02.IRMSS, it is necessary to understand inside structures and light path in IRMSS camera and receive and process calibration blackbody signals at {2. and high temperatures. Onboard blackbody calibration results of each detector are very important to relative radiometric calibration of images processing and absolute radiometric calibration of each detector. In-flight field calibration mainly contains field experiments, obtaining synchronous images, spectrum marching and MODTRAN radiative transmi- ssion computation. Radiometric cross-calibration of CBERS-02.IRMSS thermal band against TERRA MODIS selected 6 times synchronous images of two sensors passing through Lake Qinghai and Lake Taihu from August to December, 2.04.to compute the cross calibration data. Combining the in-flight field calibration and radiometric cross calibration data, the absolute radiometric calibration coefficients are calculated by the linear regression method. This new calibration model can obviously control the radiometric calibration uncertainties aroused by the single point method used in the in-flight calibration of CBERS-02.IRMSS, this kind of sensors cannot receive the cosmic background radiation. In this research, the radiometric calibration coefficients obtained through the linear regression model are 8.53 (gain, unit: DN/W m?2.r?1μm?1) and 4..92.(offset, unit: DN).

关键词： CBERS-02 IRMSS thermal band in-flight field calibration onboard blackbody calibration cross calibration.

In flight MTF monitoring and compensation for CCD camera on CBERS-02

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science china(Technological {2.) 2005年第S2期48卷 29-43页

作者： gu xingfa1,2.3, li Xiaoying1,2,4. MIN Xiangjun5, YU Tao1,2, SUN Jijuan5, ZENG Yong1,2,4. XU Hua1,2.& {4. Ding2,6 1. state key laboratory of remote Sensing science, jointly sponsored by the institute of remote Sensing {14. of Chinese academy of sciences and beijing normal university, beijing 100101, china 2. The Center for National Spaceborne Demonstration, beijing 100101, china 3. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84.14.Avignon, France 4. Graduate university of Chinese academy of sciences, beijing 100039, china 5. china Center for Resource Satellite Data and Application, beijing 100830, china 6. university of Electronic science and Technology of china, Chengdu 610054. china state key {2. of remote Sensing {4. Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University 100101 Beijing China The Center for National Spaceborne Demonstration 100101 Beijing China Institut National de la Recherche Agronomique Climat Sol Environnement 84914 Avignon France Graduate university of Chinese academy of {2. 100039 Beijing China china Center for Resource Satellite Data and Application 100830 Beijing China university of Electronic science and Technology of{2. 610054 Chengdu China

In this article, the approach of simulating ideal tarp scene was proposed to determine the MTF for CCD camera on CBERS-02. The MTF acquired from this technique was compared to those from some common methods. MTFs achieved from different approaches were employed to compensate the CCD images based on three restoration algorithms: the iterative method, the Wiener filter and the modified inverse filter (MIF). The two-dimensional MTF was established with the value at frequency 0.5 for 4.° directional MTF as the value at its four corners. This article addressed the variations of the restored CCD images with different techniques of constructing two-dimensional MTF, restoring algorithms and determining the in-flight MTFs. Results showed images restored with the MTF determined from the technique of simulating ideal tarp scene represent the real scene best. And the restoration technique based on the MIF would produce better restored images than the other two techniques. This research also demonstrated that the two-dimensional MTF used for restoration should be interpolated under the control of the MTF for 4.° axis, rather than by multiplying the cross-orbit MTF with along-orbit MTF.

关键词： CBERS-02 CCD MTF the technique of simulating ideal tarp scene.

Delay Effect on Coherent Transfer of Optical Frequency Based on a Triple-Pass Scheme

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Chinese Physics Letters 2018年第8期35卷 9-13页

作者： Chao-qun Ma li-Fei Wu Jiao gu Yan-He Chen guo-Qing Chen School of science Jiangnan UniversityWuxi 214122 Jiangsu Provincial Research Center of light Industrial Optoelectronic Engineering and Technology Jiangnan UniversityWuxi 214122 state key {2. of Precision Spectroscopy East China Normal UniversityShanghai 200062

We demonstrate a triple-pass scheme for coherent transfer of optical frequency and the delay effect on the fiber phase noise compensation. It is theoretically proved that the delay effect consists of both fiber delay and servo delay. The delay effect confines the servo bandwidth within 1/8 and induces a residual fiber phase noise after noise compensation. For a 2.-km-long fiber, the servo bandwidth is found to be around 1 k Hz, and the fiber phase noise is suppressed approaching to the theoretical limitation. The triple-pass scheme enables the simultaneous transfer of optical frequency to multiple remote users. The performance of noise compensator in the triple-pass scheme can achieve a similar level result compared with that in the double-pass scheme.

关键词： Delay Effect on Coherent Transfer of Optical Frequency Based on a Triple-Pass Scheme AOM

高分辨率定量遥感的偏振光效应与偏振遥感新领域

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遥感学报 2018年第6期22卷 901-916页

作者：晏磊顾行发褚君浩尤政刘世元 Hugh Motimor V.Chandrasekar 北京大学地球与空间科学学院遥感与地理信息系统研究所、空间信息集成与3S工程应用北京市重点实验室北京100871 中国科学院遥感与数字地球研究所北京100101 中国科学院上海技术物理研究所上海200083 清华大学精密仪器系北京100084 华中科技大学数字制造装备与技术国家重点实验室武汉430074 Rutherford Appleton laboratory Space Science and Technologies Facilities Counci Colorado state university Fort CollinsColorado 80523

随着航空航天高分辨率观测手段的逐步成熟,定量遥感在有效解决了光学地表多尺度效应后,更高分辨率的光学偏振效应在地表、大气、仪器3大要素方面逐步全面凸显出来,并直接决定或影响高分辨率观测系统的定量遥感效能实现和质量保障。例如... 详细信息

随着航空航天高分辨率观测手段的逐步成熟,定量遥感在有效解决了光学地表多尺度效应后,更高分辨率的光学偏振效应在地表、大气、仪器3大要素方面逐步全面凸显出来,并直接决定或影响高分辨率观测系统的定量遥感效能实现和质量保障。例如,植被冠层极其微弱的多次散射反射偏振效应,如果不加扣除其模型误差达到136%;大气衰减本质是大气偏振效应,是遥感反演的最大误差源,误差达到5%—30%,偏振手段扣除大气误差目前已可以降低一半以上的误差;观测仪器扣除多次散射透射偏振光后,可以实现5 nm分辨率下0.1—0.3 nm高光谱定标能力,并借助偏振强化光噪声分离出中心波长偏移和带宽退化的误差根源。借助偏振"强光弱化,弱光强化",能够实现稳定度达10^(-8)月球辐亮度基准观测,为遥感辐亮度定标不确定度由7%到1%—2.跨越提供可能。

关键词：高分辨率定量遥感偏振光效应地表偏振效应大气偏振效应仪器偏振效应偏振遥感

基于土地利用的三峡库区生态系统服务价值时空格局分析

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长江流域资源与环境 2020年第1期29卷 90-100页

作者：王大菊卫海燕贺敏辜清马明国李晶陕西师范大学地理科学与旅游学院陕西西安710119 中国科学院大学中国科学院遥感科学国家重点实验室北京100101 西南大学地理科学学院重庆400715

生态服务价值评估是对生态功能的一种经济性量化评价。以三峡库区为研究区,结合净初级生产力(NPP)、土地利用/土地覆盖变化(LUCC)、遥感(RS)、气候、国家统计数据和GIS技术,采用替代花费法、影子工程法、碳税法、市场价值法和水量平衡... 详细信息

生态服务价值评估是对生态功能的一种经济性量化评价。以三峡库区为研究区,结合净初级生产力(NPP)、土地利用/土地覆盖变化(LUCC)、遥感(RS)、气候、国家统计数据和GIS技术,采用替代花费法、影子工程法、碳税法、市场价值法和水量平衡法对三峡库区蓄水前后4.时期(2.00、2.05、2.10和2.15年)的生态系统服务价值进行量化评估,分析库区生态系统服务价值时空变异格局。结果显示:(1)从2.00年到2.15年,三峡库区生态服务总价值增加了2.9.37亿元,增长率为15.32.。(2.其中林地生态系统贡献较高,占4..14.,耕地次之,占4..04.。(3)林地生态系统服务价值随其面积的增长而增加。耕地生态系统面积减少了4.64.,但生态系统服务总价值却增加了14.54.,耕地存在不合理利用的现象。草地生态系统面积减少了16.57%,生态系统服务总价值减少了5.01%,应加强对草地生态系统的保护。总之,三峡工程的实施在整个研究区尺度上对库区生态系统服务功能的影响是利大于弊。在未来的发展中,应合理规划土地利用,制定区域发展和环境保护计划,确保三峡库区生态环境的改善和可持续发展。

关键词：生态系统服务价值三峡库区土地利用时空格局