项目名称: 高分辨地表反照率遥感模型构建与反演方法研究
项目编号: No.41305019
项目类型: 青年科学基金项目
立项/批准年度: 2014
项目学科: 天文学、地球科学
项目作者: 崔生成
作者单位: 中国科学院合肥物质科学研究院
项目金额: 25万元
中文摘要: 全球气候模型要求地表反照率的绝对精度必须达到0.02-0.05。而区域模型则强烈需求空间分辨率高于30m的地表反照率。目前的地表反照率产品,并未考虑天空光方向性分布特征,精度和分辨率均无法满足气候研究需求。高分辨卫星数据提供的有效信息量非常有限,地表反照率反演面临不稳定的共性难题,高分辨率的地表反照率产品匮乏。本项目开展高分辨地表反照率卫星遥感方法研究,探索多分辨率地物光谱数据的空间表达,研究先验知识在遥感像元尺度上的表征与应用,运用正则化理论解决地物BRDF模型反演难题,通过对遥感过程的高精度辐射传输模拟,形成天空光方向性分布的描述,构建新的地表反照率遥感模型,采用多尺度遥感数据相互比对的实验方式,检验所构建模型的真实性,解决模型多区域多气候条件应用问题,为区域气候变化研究与天气预报提供更为准确的大气边界层下垫面地表参数,为建立和应用新一代高分辨卫星地表反照率产品提供模型支持和算法参考。
中文关键词: 地表反照率;L-曲线;正则化;天空光分布;遥感反演
英文摘要: Global climate models require the absolute accuracy of surface albedo should be 0.02-0.05 units, while surface albedos with spatial resolution finer than 30m are in urgent need by regional climate models. Due to failure to take the directional distribution of skylight into account, current surface albedo products are still unable to meet the accuracy and resolution requirements for climate studies. Inasmuch as the amount of effective information provided by high-resolution satellite data is very limited, suface albedo retrievals always face common difficulties of instability, and high-resolution surface albedo is deficient. We propose a new method for satellite remote sensing of surface albedo with high-resolution data in this project.We will explore spatial expressions of mutiresolution surface spectral reflectance data, study the characterizations and applications of a priori knowledge at the scale of remote sensing pixels, and empoly regularization theory to overcome the problem of surface BRDF models inversion. Based on high accuracy radiative transfer simulations of remote sensing processes, an approach will be established for describing the directional distribution of diffuse skylight. Then, a novel remote sensing model for surface albedos will be constructed. Validation of the constructed model will be pe
英文关键词: surface albedo;L-curve;regularization;skylight distribution;remote sensing inversion