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The influence of runoff and wind on the dispersion patterns of suspended sediment in the Zhujiang(Pearl) River Estuary based on MODIS data

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Acta Oceanologica Sinica 2019年第3期38卷 26-35页

作者： Suying Ou Qingshu Yang Xiangxin Luo Fan Zhu Kaiwen Luo Hao Yang Institute of Estuarine and Coastal Research School of Marine Sciences Sun Yat-sen University State-province Joint Engineering Laboratory of Estuarine Hydraulic Technology

Cloud-free moderate-resolution imaging spectroradiometer(MODIS) images of the Zhujiang(Pearl) River Estuary(ZRE) taken between 2002 and 2012 are retrieved and used to study the spatial and temporal patterns of suspended sediment concentrations(SSCs) across the estuary under runoff, wind, and tropical storm *** typical dispersal patterns of suspended sediments in the estuary are defined: Case I shows generally low SSCs under low dynamics; Case Ⅱ shows a river-dominant dispersal pattern of suspended sediments from the outlets,particularly from Modaomen, Jiaomen, Hengmen, and others; Case Ⅲ shows wind-dominant dispersal of high SSCs derived from the west shoal and southwesterly transport under a strong NE wind; Case IV is the combination of relatively large runoff and wind; and Case V is caused by a strong tropical storm with high river discharge and wind, which is characterized by the high SSCs across the entire estuary that are transported eastward by winddriven and buoyancy currents outside the estuary. Runoff is a dominant factor that controls seasonal and annual SSC variations in the ZRE, with the area of high SSCs being largest in the summer and smallest in the spring. The correlation coefficients between the monthly averaged river-suspended sediment discharge and the area of the high SSCs are approximately 0.6. The wind power over the west shoal increases with a wind speed, which induces more sediment resuspension and shows a close relationship between the wind speed and high SSC area.

关键词： Zhujiang(Pearl) River Estuary suspended sediment concentration(SSC) moderate-resolution imaging spectroradiometer wind runoff tides

Remote Detection of Varying Water Storage in Relation to Surfacial Temperature of Aral Sea

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Chinese Geographical Science 2019年第5期29卷 741-755页

作者： MU Guangyi CHEN Li HU Liangjun SONG Kaishan Key Laboratory for Vegetation Ecology Science Ministry of EducationNortheast Normal UniversityChangchun130024China Jilin Provincial Museum of Nature Northeast Normal UniversityChangchun130117China Northeast Institute of Geography andAgroecology Chinese Academy of SciencesChangchun130102China

Lake monitoring by remote sensing is of significant importance to understanding the lake and ambient ecological and environmental processes. In particular, whether lake water storage variation could predict lake surfacial temperature or vice versa has long fascinated the research community, in that it would greatly benefit the monitoring missions and scientific interpretation of the lake change processes. This study attempted to remotely detect the dynamics of the Aral Sea and pursue the relationships between varying lake water storage attributes and surface water temperature by using MODIS LST(moderate-resolution Imaging Spectroradiometer Land Surface Temperature) 8-day composite products, satellite altimeter data, and actual meteorological measurements. Their associations with lake Surface Water Temperatures(SWT) were then analyzed. Results showed the lake water surface areas and elevations of the North Aral Sea tended to increasing trend from 2001(2793.0 km^2, 13.6 m) to 2015(6997.8 km^2, 15.9 m), while those of the South Aral Sea showed a decreasing trend during 2001(20 434.6 km^2, 3.9 m) and 2015(3256.1 km^2, 0.9 m). In addition, the annual daytime and nighttime lake SWT both decreased in the North Aral Sea, while only the daytime SWT in the South Aral Sea exhibited an increase, indicating a rising deviation of diurnal temperatures in the South Aral Sea during the past 15 yr. Moreover, a lower correlation was found between variations in the daytime SWT and storage capacity in the South Aral Sea(R^2 = 0.33;P < 0.05), no fair correlations were tested between lake water storage and daytime SWT in the North Aral Sea nor between lake water storage and nighttime SWT in either part of the sea. These results implied that climate change, if any at least during the research period, has no significant effects on lake dynamics over the two sectors of the Aral Sea with anthropogenic disturbances. However, climate change and human activities may overlap to explain complex co

关键词： Surface Water Temperature(SWT) lake water surface dynamics lake water storage moderate-resolution Imaging Spectroradiometer(MODIS) the Aral Sea

基于可见光红外成像辐射仪数据的地表温度反演

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农业工程学报 2014年第8期30卷 109-116,F0003页

作者：夏浪毛克彪马莹孙知文赵芬中国农业科学院农业资源与农业区划研究所呼伦贝尔草原生态系统国家野外科学观测研究站北京100081 广州地理研究所广州510070 航天恒星科技有限公司北京100086

地表温度是农业旱灾和作物估产模型的重要参数。该文针对可见光红外成像辐射仪(visible infrared imager radiometer suite,VIIRS)传感器缺乏水汽通道的特点,联合Aqua卫星搭载的中分辨率成像光谱仪(moderate-resolution imaging spectro... 详细信息

地表温度是农业旱灾和作物估产模型的重要参数。该文针对可见光红外成像辐射仪(visible infrared imager radiometer suite,VIIRS)传感器缺乏水汽通道的特点,联合Aqua卫星搭载的中分辨率成像光谱仪(moderate-resolution imaging spectroradiometer,MODIS)数据提出了基于分裂窗算法的VIIRS地表温度反演方法。对地表发射率和大气透过率这2个关键参数的获取进行了详细分析,选取了处于作物生长期的2013年6月4日VIIRS数据进行实例验证分析。结果表明,与全国气象数据比较该文算法在大尺度上能够较好地获取中国地表温度;与MODIS数据温度产品在高温产粮区比较,该文算法与MODIS温度产品精度较一致,两者差值小于1 K。使用MODTRAN(moderate resolution transmission)软件对算法的精度进行了模拟评价验证,分析表明:在一定的水汽和地表发射率条件下,算法反演精度一般保持在1 K内,平均误差为0.431 K,误差标准偏差为0.247 K。能够为农业干旱、作物长势等农情信息监测提供所需的地表温度数据。

关键词：遥感温度水汽传感器可见光红外成像辐射仪反演中分辨率成像光谱仪 visible infrared imager radiometer suite (VIIRS) moderate-resolution imaging spectroradiometer (MODIS)