Monitoring glacier changes in Disko Island, Greenland Using Object-based image Analysis in Google Earth Engine

Description

Climate change is having an impact on glaciers, which are melting at an alarming rate around the world. Temporal observations in glacier extent are vital for understanding the impact of climate change, but they are not widely available in many parts of the world. Temperatures are rising twice as quickly in the Arctic as anywhere else on the earth, and meltwater is contributing significantly to global sea-level rise. Therefore, it is important to quantify glacier recession within this sensitive region. In this study, an object-based image analysis (OBIA) method is applied to multispectral Landsat satellite images in Google Earth Engine (GEE) to map 732 glaciers on Disko Island (Qeqertarsuaq), Greenland, to quantify glacier area at three different points in time: 1985, 2001, and 2019. The results confirm that in 1985, the total glacierized area was 1928.03 km2, in 2001 the area was 1774.39 km2, and by 2019 there was an 23.25% reduction in glacier area to 1479.69 km2. Comparison between manually corrected glacier outlines taken from the Randolph Glacier Inventory (RGI) and the mapped glacier outlines derived using the OBIA method shows there is a 90.26% similarity between both datasets. This confirms that combining OBIA with the GEE platform is a potential approach for accurately mapping glaciers, reduces the time required for manual correction, and can be applied in other glacierized regions for rapid assessment of glacier change.

Period	26 Mar 2022 → 1 Apr 2022
Event title	Arctic Summer Science Week - International Arctic Science Committee
Event type	Conference
Location	Tromsø, NorwayShow on map
Degree of Recognition	International