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Semi-automated open water iceberg detection from Landsat applied to Disko Bay, West Greenland 应用于西格陵兰迪斯科湾的陆地卫星半自动化开放水域冰山探测

The journal of glaciology Pub Date : 2019-05-15 DOI: 10.1017/jog.2019.23

J. Scheick, E. Enderlin, G. Hamilton

{"title":"Semi-automated open water iceberg detection from Landsat applied to Disko Bay, West Greenland","authors":"J. Scheick, E. Enderlin, G. Hamilton","doi":"10.1017/jog.2019.23","DOIUrl":"https://doi.org/10.1017/jog.2019.23","url":null,"abstract":"ABSTRACT Changes in Greenland's marine-terminating outlet glaciers have led to changes in the flux of icebergs into Greenland's coastal waters, yet icebergs remain a relatively understudied component of the ice-ocean system. We developed a simple iceberg delineation algorithm for Landsat imagery. A machine learning-based cloud mask incorporated into the algorithm enables us to extract iceberg size distributions from open water even in partially cloudy scenes. We applied the algorithm to the Landsat archive covering Disko Bay, West Greenland, to derive a time series of iceberg size distributions from 2000–02 and 2013–15. The time series captures a change in iceberg size distributions, which we interpret as a result of changes in the calving regime of the parent glacier, Sermeq Kujalleq (Jakobshavn Isbræ). The change in calving style associated with the disintegration and disappearance of Sermeq Kujalleq's floating ice tongue resulted in the production of more small icebergs. The increased number of small icebergs resulted in increasingly negative power law slopes fit to iceberg size distributions in Disko Bay, suggesting that iceberg size distribution time series provide useful insights into changes in calving dynamics.","PeriodicalId":92731,"journal":{"name":"The journal of glaciology","volume":"80 1","pages":"468 - 480"},"PeriodicalIF":0.0,"publicationDate":"2019-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83858447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 7

A Complete Map of Greenland Ice Velocity Derived from Satellite Data Collected over 20 Years. 根据20年来收集的卫星数据绘制的格陵兰冰速度完整地图。

The journal of glaciology Pub Date : 2018-02-01 Epub Date: 2017-11-21 DOI: 10.1017/jog.2017.73

Ian Joughin, Ben E Smith, Ian M Howat

引用次数: 0

A SAR Record of Early 21^st Century Change in Greenland. 格陵兰岛21世纪初变化的SAR记录。

The journal of glaciology Pub Date : 2016-02-01 Epub Date: 2016-03-16 DOI: 10.1017/jog.2016.10

Ian Joughin, Ben E Smith, Ian M Howat, Twila Moon, Ted A Scambos

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引用次数: 0