The algorithms of extracting chlorophyll-a （Chl-a） concentration have been established for Chinese moderate resolution imaging spectrometer （CMODIS） mounted on Shenzhou-3 spaceship launched on 25 March 2002. The C...The algorithms of extracting chlorophyll-a （Chl-a） concentration have been established for Chinese moderate resolution imaging spectrometer （CMODIS） mounted on Shenzhou-3 spaceship launched on 25 March 2002. The CMODIS is an ocean color sensor with 30 visible channels and 4 infrared channels, much different from other ocean color satellites and needs new algorithms to process data. Three models of Chl-a concentration were established based on Chl-a data retrieved from sea-viewing wide field-ofview sensor （SeaWiFS）, with the average relative errors of 26. 6%, 24%. 0% and 33.5%, respectively. This practical and economic approach can be used for developing the algorithms of Chinese ocean color and temperature sensor （COCTS） on the satellite Haiyang-1 to derive the Chl-a concentration concentration distribution. The applicability of the algorithms was analyzed using some in situ measurements. Suspended sediment is the main factor influencing the accuracy of the spectral ratio algorithms of Chl-a concentration. The algorithms are suitable to using in the regions where suspended sediment concentrations （ SSC ） are less than 5 g/m^3 under the condition of relative error of Chl-a concentration retrieval within 35%. High concentration of suspended sediment leads to the overestimate remote sensing retrieval of concentration of Chl-a, while low-middle SSCs lead to the low Chl-a concentration values using the spectral ratio algorithms. Since the accuracy of Chl-a concentration by the spectral ratio algorithms is limited to waters of Case 2, it is necessary to develop semi-analytical models to improve the performance of satellite ocean color remote sensing in turbid coastal waters.展开更多
The third spaceship SZ 3 of China was launched in March 2002, in which the payload is Chinese moderate imaging spectra ra diometer (CMODIS). In this paper, first, the properties and characteristics of CMODIS are brief...The third spaceship SZ 3 of China was launched in March 2002, in which the payload is Chinese moderate imaging spectra ra diometer (CMODIS). In this paper, first, the properties and characteristics of CMODIS are briefly introduced; second, the quality and availability are evaluated by means of the Complex signal noise ratio (CSNR) which is simulated theoretically; third, the received CMODIS data are compared with the Sea wide field of view sensor (SeaWiFS) / SeaSTAR data to understand the accuracy of radiance measurement by CMODIS; finally, the remote sensing products of ocean color and temperature are mapped by CMODIS to study its marine application potentiality. The results show that CMODIS has its latent capability for the application of marine environment detection, the management and protection of marine resources, and the national rights and interests. Meanwhile some suggestions are proposed to modify the next ge neration sensor on the Chinese spaceship.展开更多
During the 3rd mission of Chinese Unmanned Spacecraft the application sys tem of "SZ-3" (Shenzhou, a divine ship) gets a great success, all its goals are achieved. Many areas of science and breakthrough tech...During the 3rd mission of Chinese Unmanned Spacecraft the application sys tem of "SZ-3" (Shenzhou, a divine ship) gets a great success, all its goals are achieved. Many areas of science and breakthrough technology, including earth observation, earth environment monitoring, space material, space life science etc., are carried out in the mission. There are 44 payload instruments totally.All the instruments are working well during the orbit flight and a lot of good results are obtained. Many areas, for example the moderate resolution imag ing spectroradiometer, the solar ultraviolet spectral irradiance monitor and the space protein crystallization facility perform better than required and expected.A brief introduction of the experiments and the achievements of the mission is given in this paper.展开更多
基金This study was supported by the National Natural Science Foundation of China under contract Nos 40576080 and 40006011the National"863"Program of China under contract Nos 2002AA639220 and 2007AA12Z182.
文摘The algorithms of extracting chlorophyll-a （Chl-a） concentration have been established for Chinese moderate resolution imaging spectrometer （CMODIS） mounted on Shenzhou-3 spaceship launched on 25 March 2002. The CMODIS is an ocean color sensor with 30 visible channels and 4 infrared channels, much different from other ocean color satellites and needs new algorithms to process data. Three models of Chl-a concentration were established based on Chl-a data retrieved from sea-viewing wide field-ofview sensor （SeaWiFS）, with the average relative errors of 26. 6%, 24%. 0% and 33.5%, respectively. This practical and economic approach can be used for developing the algorithms of Chinese ocean color and temperature sensor （COCTS） on the satellite Haiyang-1 to derive the Chl-a concentration concentration distribution. The applicability of the algorithms was analyzed using some in situ measurements. Suspended sediment is the main factor influencing the accuracy of the spectral ratio algorithms of Chl-a concentration. The algorithms are suitable to using in the regions where suspended sediment concentrations （ SSC ） are less than 5 g/m^3 under the condition of relative error of Chl-a concentration retrieval within 35%. High concentration of suspended sediment leads to the overestimate remote sensing retrieval of concentration of Chl-a, while low-middle SSCs lead to the low Chl-a concentration values using the spectral ratio algorithms. Since the accuracy of Chl-a concentration by the spectral ratio algorithms is limited to waters of Case 2, it is necessary to develop semi-analytical models to improve the performance of satellite ocean color remote sensing in turbid coastal waters.
文摘The third spaceship SZ 3 of China was launched in March 2002, in which the payload is Chinese moderate imaging spectra ra diometer (CMODIS). In this paper, first, the properties and characteristics of CMODIS are briefly introduced; second, the quality and availability are evaluated by means of the Complex signal noise ratio (CSNR) which is simulated theoretically; third, the received CMODIS data are compared with the Sea wide field of view sensor (SeaWiFS) / SeaSTAR data to understand the accuracy of radiance measurement by CMODIS; finally, the remote sensing products of ocean color and temperature are mapped by CMODIS to study its marine application potentiality. The results show that CMODIS has its latent capability for the application of marine environment detection, the management and protection of marine resources, and the national rights and interests. Meanwhile some suggestions are proposed to modify the next ge neration sensor on the Chinese spaceship.
文摘During the 3rd mission of Chinese Unmanned Spacecraft the application sys tem of "SZ-3" (Shenzhou, a divine ship) gets a great success, all its goals are achieved. Many areas of science and breakthrough technology, including earth observation, earth environment monitoring, space material, space life science etc., are carried out in the mission. There are 44 payload instruments totally.All the instruments are working well during the orbit flight and a lot of good results are obtained. Many areas, for example the moderate resolution imag ing spectroradiometer, the solar ultraviolet spectral irradiance monitor and the space protein crystallization facility perform better than required and expected.A brief introduction of the experiments and the achievements of the mission is given in this paper.
