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21.
青藏高原积雪的分布特征及其对地面反照率的影响 总被引:7,自引:3,他引:7
通过对1983年7月至1990年6月青藏高原主体58个格点积雪资料进行EOF分析发现,青藏高原主体积雪分布以西部兴都库什山脉。天山山脉以及南部喜马拉雅山脉为主;高原中部唐古拉山脉、北部昆仑山脉和东部巴颜喀拉山脉的积雪相对较少,青藏高原西部、南部的积雪变化与中部、北部和东部的积雪变化趋势存在反位相关系。另外,本文还对积雪对高原地面反照率的影响作了简单分析。 相似文献
22.
To build land surface dataset for climate model,with application of remote sensing techniqueas well as the Geographic Information System(GIS),the data of surface type,roughness andalbedo over China in 1997 were retrieved,resolutions being 10 km×10 km.Based on these data,an analysis is conducted on the geographic distributions and seasonal variations of surfacevegetation cover and roughness as well as albedo over China.Results show that surface vegetationcover is mainly located to the south of Yangtze River,in Southwest and Northeast China andsparse vegetation cover is in the Northwest.The variation of land surface cover affects thevariations of land surface roughness and albedo.High albedo occurred in the north of XinjiangAutonomous Region,the north of Northeast China and the Qinghai-Xizang Plateau in winter,incorrespondence with the location of snow cover.For most part of China,surface roughness decreases and albedo increases in winter,while theroughness increases and the albedo decreases in summer,which could mainly result from landsurface cover(snow cover and vegetation cover)and soil moisture changes.This shows that thegeographic distribution and seasonal variation of the albedo are almost opposite to those of theroughness,in agreement with theoretical results.Temporally,the amplitude of surface roughnesschange is quite small in comparison with the roughness itself. 相似文献
23.
To build land surface dataset for climate model,with application of remote sensing technique as well as the Geographic Information System(GIS),the data of surface type,roughness and albedo over China in 1997 were retrieved,resolutions being 10 km×10 km.Based on these data,an analysis is conducted on the geographic distributions and seasonal variations of surface vegetation cover and roughness as well as albedo over China.Results show that surface vegetation cover is mainly located to the south of Yangtze River,in Southwest and Northeast China andsparse vegetation cover is in the Northwest.The variation of land surface cover affects the variations of land surface roughness and albedo.High albedo occurred in the north of Xinjiang Autonomous Region,the north of Northeast China and the Qinghai-Xizang Plateau in winter,in correspondence with the location of snow cover.For most part of China,surface roughness decreases and albedo increases in winter,while the roughness increases and the albedo decreases in summer,which could mainly result from land surface cover(snow cover and vegetation cover)and soil moisture changes.This shows that the geographic distribution and seasonal variation of the albedo are almost opposite to those of the roughness,in agreement with theoretical results.Temporally,the amplitude of surface roughness change is quite small in comparison with the roughness itself. 相似文献
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25.
兰州冬季气溶胶光学特性的参数化 总被引:9,自引:1,他引:9
兰州冬季气溶胶的谱分布用双谱模式拟合,即Junge谱加Deirmendjian谱;气溶胶的平均折射率为1.549-0.1i;气溶胶浓度随高度的分布根据天气条件取为高斯、均匀、指数分布三种类型。以此为基础,计算出兰州冬季气溶胶光学厚度的平均值。 经实测的气溶胶光学厚度与本文的计算值比较后发现,我们的参数化方案基本上是成功的。 相似文献
26.
本文利用1986-1990年我国14个具有地理、气候代表性的日射观测的实测资料,分析了我国地面反射率的若干最新特征,为认识和研究我国地理和气候变化提供了某些依据。 相似文献
27.
用NCEP/NCAR再分析辐射资料估算月平均地表反照率 总被引:16,自引:1,他引:15
本文利用1979年 ̄1995年17年平均的NCEP/NCAR(National Center for Environmen-tal Prediction/National Center for Atmospheric Research,美国国家环境预报中心/美国国家大气研究中心)再分析辐射资料估算了全球月平均地表反照率.从所得结果的时空分布来看,用NCEP/NCAR辐射资料得到的全球地表反照率基本 相似文献
28.
The advantages of using unmanned underwater vehicles in coastal ocean studies are emphasized. Two types of representative vehicles, remotely operated vehicle (ROV) and autonomous underwater vehicle (AUV) from University of South Florida, are discussed. Two individual modular sensor packages designed and tested for these platforms and field measurement results are also presented. The bottom classification and albedo package, BCAP, provides fast and accurate estimates of bottom albedos, along with other parameters such as in-water remote sensing reflectance. The real-time ocean bottom optical topographer, ROBOT, reveals high-resolution 3-dimentional bottom topography for target identification. Field data and results from recent Coastal Benthic Optical Properties field campaign, 1999 and 2000, are presented. Advantages and limitations of these vehicles and applications of modular sensor packages are compared and discussed. 相似文献
29.
30.
Application of ensemble kalman filter to geophysical parameters retrieval in remote sensing:A case study of kernel-driven BRDF model inversion 总被引:2,自引:0,他引:2
QIN Jun YAN Guangjian LIU Shaomin LIANG Shunlin ZHANG Hao WANG Jindi LI Xiaowen 《中国科学D辑(英文版)》2006,49(6):632-640
Remote sensing can provide multi-spatial resolution, multi-temporal resolution multi-spectral band and multi-angular data for the observation of land surface. At present, one of research focuses is how to make the best of these data to retrieve geophysical parameters in conjunction with their a priori knowledge and simul-taneously consider the influence of data uncertainties on inversion results[1-5]. The essence of remote sensing lies in inversion. It is difficult to precisely retrieve parame… 相似文献