基于Google Earth Engine平台的青藏高原冰川变化研究——以普若岗日冰原为例  

Glacier changes on the Qinghai-Tibet Plateau based on Google Earth Engine:A case study of the Purog Kangri glacier

作　　者：田梦祺 段克勤 石培宏 Tian Mengqi;Duan Keqin;Shi Peihong(School of Geography and Tourism,Shaanxi Normal University,Xi’an 710119,Shaanxi,China)

机构地区：[1]陕西师范大学地理科学与旅游学院,陕西西安710119

出　　处：《地理科学》2023年第6期943-951,共9页Scientia Geographica Sinica

基　　金：第二次青藏高原综合科学考察研究项目(2019QZKK0201);国家自然科学基金项目(41571062);中国博士后基金项目(2017M610622)资助

摘　　要：基于Google Earth Engine(GEE)云计算平台,以青藏高原中部的普若岗日冰原为例,探讨了快速批量处理遥感数据并获取冰川面积变化的方法。结果表明,利用GEE平台结合像元级影像合成和最小归一化积雪指数(Normalized Difference Snow Index,NDSI),可快速获取年度合成影像,提取冰川边界。通过对1988—2020年共512景遥感影像合成计算,获得了1988—2020年普若岗日冰川面积变化特征,分析发现:33 a间冰川面积减小了31.08 km^(2),年均退缩率为0.23%/a,冰川面积退缩主要发生在冰川末端,部分末端在20 a间退缩了1506 m。相对于冰川的实地观测或传统遥感监测法,本方法提高了影像利用率和数据处理效率,可快速实现冰川面积变化长时序分析,为现代冰川变化研究提供了新途径。Based on the Google Earth Engine(GEE)cloud computing platform,this article explores a method to rapidly batch process remote sensing data and obtain glacier area changes based on the Purog Kangri Icefield on the central Qinghai-Tibet Plateau as an example.A pixel-by-pixel synthesis algorithm is used to acquire cloud-free images of the study area,which improves the utilization of image data.By calculating the NDSI of the study area and performing the minimum value synthesis,the glacier extent of the Purog Kangri from 1988 to 2020 was extracted to study the changes of the glacier area of the Purog Kangri in the past 33 years.The results show that the GEE platform combined with image-level image synthesis and the minimum NDSI algorithm can be used to rapidly acquire annual synthetic images and extract glacier boundaries.The glacier area change characteristics were obtained from 1988 to 2020 by synthesizing 512 remote sensing images from 1988 to 2020,and the glacier area decreased by 31.08 km^(2) in past 33 years,with an average annual retreat rate of 0.23%/a.The glacier area retreat mainly occurred at the end of the glacier,and some of the ends retreated 1506 m in 20 years.In comparison with the results of other related studies,the absolute error between the results of this paper and the reference value is within 5.6 km2 and the relative deviation is within 1.4%,which proves that the minimum NDSI synthesis method based on the GEE platform is feasible and reliable to extract the glacier area.Compared with field observation of glaciers or traditional remote sensing monitoring methods,this method improves image utilization and data processing efficiency,and can quickly realize long time series analysis of glacier area change,which provides a new way for modern glacier change research.

关 键 词：GOOGLE EARTH ENGINE 普若岗日冰原 云计算 

分 类 号：P343.6[天文地球—水文科学]