格陵兰以北海域卫星激光测高的回波模型与地物分类

项目名称： 格陵兰以北海域卫星激光测高的回波模型与地物分类

项目编号： No.41506210

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 海洋科学

项目作者： 马跃

作者单位： 山东科技大学

项目金额： 20万元

中文摘要： 准确监测极地平均海面与海冰变化，是极地海洋科学研究的基础，而正确分类海水与海冰，又是监测工作的前提。近年来，具有光斑直径小等优点的卫星激光测高在极地研究中效果显著，具有良好的应用前景。项目拟通过建立极地海域海水、海冰、覆盖积雪的海冰三种地物的激光脉冲回波模型，计算不同地物的回波宽度、峰度等参数的理论范围作为首要分类依据；设计波形处理算法提取GLAS实测回波参数，以其统计特性作为辅助分类依据；使用机载Lidar和NCEP气象数据作为地表先验信息，以格陵兰以北海域为例，训练监督分类方法实现三种地物分类。通过分类后的GLAS数据计算该区域海冰干舷，与同时同地的机载Lidar计算结果进行对比，验证分类的正确性。项目将分类特征参数模型化和半定量化，其对极地海域地物分类精度，比目前基于统计特性的激光测高地物分类方法将有明显改善；所建立的回波模型对我国用于极地测量星载激光测高仪的系统参数设计有参考意义。

中文关键词： 北冰洋海冰；激光测高；回波模型；地物分类；海冰干舷

英文摘要： The accurate changing of mean sea level and sea ice is the foundation of developing marine science research in the polar regions, and precise classification of water and sea ice data is essential precondition of monitoring. In recent years, owing to many advantages such as smaller footprint, space-borne laser altimeter has acquired a great of achievements in the field of polar science, and has a promising application prospect. This project proposes that through establishing the laser pulse echo theoretical models including water, sea ice, and snow-covered ice, for different surface categories the theoretical ranges of waveform parameters, e.g. width, kurtosis, etc, are calculated as the primary basis of classification. The statistical characters of GLAS waveform parameters, which are extracted by the designed waveform processing algorithm, are calculated as the auxiliary basis of classification. Using airborne Lidar data and NCEP meteorological data as prior information of earth surface, a new supervised surface category method will be designed and trained to complete the three kinds of surface type classification in the north waters of Greenland. The sea ice freeboard will be retrieved on the north of Greenland using the classified GLAS elevation data, which will be contrasted with the results calculated by airborne Lidar data at the same time and region, in order to verify the precision of classification. This research will form a new method of surface category based on analytical model and semi quantitative, and compared to the current method based on statistical character, the precision of classification will be significantly improved. Besides, the established echo theory and waveform simulator are meaningful for system parameter design of space-borne laser altimeter used for polar region monitoring.

英文关键词： Arctic sea ice ;laser altimeter;waveform model;surface type classification;sea ice freeboard