极地研究

极地研究 ›› 2022, Vol. 34 ›› Issue (4): 432-440.DOI: 10.13679/j. jdyj.20210078

• 研究论文 • 上一篇    下一篇

基于遥感的2015—2020年环南极冰山空间分布研究

张卓宇1  刘蕾2  刘旭颖1  戚梦真1   

  1. 1北京师范大学全球变化与地球系统科学研究院, 遥感科学国家重点实验室, 北京 100875; 
    2墨尔本大学工程学院, 墨尔本 3000
  • 出版日期:2022-12-31 发布日期:2023-01-11
  • 作者简介:张卓宇, 女, 1997年生。硕士, 主要从事极地遥感研究工作。E-mail: 201921490047@mail.bnu.edu.cn
  • 基金资助:
    国家自然科学基金(41830536)资助

The spatial distribution of icebergs around Antarctica from 2015 to 2020 based on remote sensing

Zhang Zhuoyu1, Liu Lei2, Liu Xuying1, Qi Mengzhen1   

  1. 1State Key Laboratory of Remote Sensing Science, College of Global Change and Earth System Science, Beijing Normal University,Beijing 100875, China;
    2Melbourne School of Engineering, Melbourne 3000, Australia
  • Online:2022-12-31 Published:2023-01-11

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摘要： 冰山是因冰架各部分运动速度不均, 裂隙生长后贯穿冰架发生崩解而产生的大块淡水冰。作为南大洋中重要的移动淡水源, 冰山的运动和融化可以释放淡水并将其扩散至远离南极大陆的其他海域, 因此, 研究冰山的时空分布和面积分布提取可为研究南大洋的水文、生态乃至全球气候变化产生的影响提供数据基础, 具有重要意义。本文采用卫星合成孔径雷达观测数据开展南极冰山追踪研究。基于Google Earth Engine遥感大数据平台, 合成了2015年8月—2020年8月欧空局Sentinel-1 SAR传感器影像数据集, 经过分块重采样、下载拼接等步骤, 获得冬季3天内环南极400 km影像镶嵌图; 应用栅格分析功能得到研究期的二值化影像, 使用数据转换和几何计算等功能提取了单个冰山的面积、周长。结果表明, 南极冰山大量聚集于海岸线50 km以内区域, 其中超小型冰山数量占比接近于50%, 小型冰山可能在南极淡水输入中扮演了举足轻重的角色。

关键词: 南极, 冰山, 遥感, 空间分布

Abstract: Icebergs are large pieces of ice produced by the disintegration of ice shelves following crack growth due to the uneven movement speed of each part of ice shelves. The movement and melting of icebergs can transport and subsequently release freshwater to parts of the Southern Ocean that are distant from the Antarctic continent. Accordingly, studying the temporal and spatial distribution of icebergs can provide insights related to the hydrology, ecology, and even the impacts of global climate change across the Southern Ocean. Extracting the iceberg area distribution from remotely sense imagery provides a data basis for such investigations. Using Google Earth Engine, the image dataset of ESA Sentinel-1 SAR images from August 2015 to August 2020 were synthesized. After block resampling, downloading, and splicing, a mosaic map of 400 km around the South Pole within 3 days in winter was obtained; a binary image was then obtained using the grid analysis function, and the area and perimeter of each iceberg was extracted by using data conversion and geometric calculation functions. The results show that many Antarctic icebergs are concentrated within 50 km of the coastline, of which ultra-small icebergs account for nearly 50%. As such, small icebergs may play an important role in the input of fresh water in Antarctica.

Key words: Antarctica, icebergs, remote sensing, spatial distribution