被动微波遥感反演冻土未冻水含量的机理研究

项目名称： 被动微波遥感反演冻土未冻水含量的机理研究

项目编号： No.41301356

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： 赵少杰

作者单位： 北京师范大学

项目金额： 25万元

中文摘要： 冻土是冰冻圈的重要组分之一，对全球气候变化及水循环具有重要意义。未冻水含量是冻土的一个重要的物理参数，对全球变化和陆面过程研究中的冻土过程参数化模型具有重要的意义。微波遥感对地表的水分具有较高的敏感性。本课题围绕冻土的微波辐射机理展开研究，面向发展一种利用被动微波遥感反演冻土中未冻水含量的方法。本项目的研究内容包括三部分：冻土介电常数研究、冻土微波辐射特征和机理研究以及冻土中未冻水含量的反演算法开发和验证。本课题的创新点在于定量描述未冻水含量对冻土微波辐射的影响，从机理角度弄清楚冻土微波辐射的亮温梯度随温度变化的原因。项目从实验出发，获取冻土微波辐射与未冻水含量的规律，结合模型和理论推导，建立冻土未冻水含量的反演算法，并在地面尺度和像元尺度进行验证。

中文关键词： 冻土；未冻水；微波遥感；介电常数；反演

英文摘要： Frozen soil is one of the important component of the cryosphere, and has important implications for global climate change and hydrologic cycle. Unfrozen water, which is important to the parameterization of frozen soil processes in land surface processes reasearch is one of the most important physical parameter of frozen soil. Microwave remote sensing is sensitive to the water of land surface. This project will study on the mechanism of the microwave emission of frozen soil in order to develop a method to retrieve the unfrozen water content of frozen soil using passive microwave remote sensing. The content of this project includes: the study of the dielectric constant of frozen soil, the microwave radiation of frozen soil and the development and validation of the algorithm of retrieving the unfrozen water content of frozen soil. The innovation of this project is that it study the relationship between the microwave radiation and the unfrozen water content of frozen soil and explain the reason of the spectral gradient of microwave radiation of frozen soil changing with the physical temperature of frozen soil. The research will start with field experiment, combine model simulation and theoretical derivation to establish and validate a retrieval method of the unfrozen water content of frozen soil.

英文关键词： frozen soil；unfrozen water；microwave remote sensing；dielectric constant；retrieval