摘要
高原湖泊面积在冰川和降水作用下不断扩大,湖冰作为指示全球气候变化的敏感因素之一极具研究价值。基于天宫二号遥感数据,通过对比平行六面体、最小距离法、最大似然法及支持向量机,发现支持向量机对于湖冰提取具有更显著的优势。使用支持向量机对色林错湖区2017~2018年7景遥感影像进行湖冰提取,结合当地气象数据,发现总体精度高于88.58%,7景中6景影像分类精度高于95%;色林错湖于12月份开始封冻,直至1月底完全封冻,并于次年3月开始消融,4月实现全面消融;温度、水系、盐度均不同程度地影响色林错湖的封冻-消融过程。温度为色林错湖冰生消过程的主因,水系的注入延缓了色林错西部、西南部以及北部区域封冻,而盐度则导致湖冰生消与温度变化不完全一致,封冻时间推迟、消融时间提早。
Due to the global climate change and the melting glacier,plateau lakes are rapidly increasing and lake ice is indeed worthy of study as a sensitively inductive factor of global climate change.Based on the remote sensing data of Tiangong-2,the methods of parallelepiped,minimum distance,maximum likelihood and support vector machine were compared.It was found that the support vector machine was obviously better than the other methods with an overall classification accuracy surpassed 88.58%.Then the SVM method was used to extract the lake ice from Selin Co’s remote-sensing images in the time span from 2017 to 2018.Combining with the local meteorological data,the results indicated that Selin Co lake started to freeze in December and frozen completely at the end of January.It began to melt in March and melted completely in April.In addition,the process of freezing and melting in Selin Co was influenced by temperature,salinity and river system in different degrees.Temperature was the main cause of freezing and melting.River injection caused the slower freezing area distributed in the west,southwest and north of Selin Co.While salinity made the freezing and melting in Selin Co not in complete accordance with temperature,the freezing was delayed and melting was earlier.
作者
王琼
王君波
郭俊钰
梁继
WANG Qiong;WANG Junbo;GUO Junyu;LIANG Ji(National-Local Joint Engineering Laboratory of Geo-Spatial information Technology,HunanUniversity of Science and Technology,Xiangtan 411201,China;Key Laboratory of Tibetan Environment Changes and Land Surface Processes,Institute of Tibetan Plateau Research,CAS,Beijing 100101,China;School of Resource&Environment and Safety Engineering,Hunan University of Science and Technology,Xiangtan 411201,China)
出处
《载人航天》
CSCD
北大核心
2019年第6期789-798,共10页
Manned Spaceflight
基金
国家自然科学基金(41671351)
湖南省自然科学基金(2018JJ2117)
湖南科技大学科技创新“卓越学子”培育计划项目(EY180104)
湖南科技大学科研创新团队建设项目(CXTD004)
关键词
色林错
湖冰
支持向量机
天宫二号
监督分类
Selin Co
lake ice
support vector machine
Tiangong-2
supervised classification
