Glacier facies mapping using a machine-learning algorithm

Glacier facies mapping using a machine-learning algorithm: The Parlung Zangbo Basin case study

Zhang, Jingxiao (Chinese Academy of Sciences)
Jia, Li (Chinese Academy of Sciences)
Menenti, M. (TU Delft Optical and Laser Remote Sensing; Chinese Academy of Sciences)
Hu, Guangcheng (Chinese Academy of Sciences)

2019

Glaciers in the Tibetan Plateau are an important indicator of climate change. Automatic glacier facies mapping utilizing remote sensing data is challenging due to the spectral similarity of supraglacial debris and the adjacent bedrock. Most of the available glacier datasets do not provide the boundary of clean ice and debris-covered glacier facies, while debris-covered glacier facies play a key role in mass balance research. The aim of this study was to develop an automatic algorithm to distinguish ice cover types based on multi-temporal satellite data, and the algorithm was implemented in a subregion of the Parlung Zangbo basin in the southeastern Tibetan Plateau. The classification method was built upon an automated machine learning approach: Random Forest in combination with the analysis of topographic and textural features based on Landsat-8 imagery and multiple digital elevation model (DEM) data. Very high spatial resolution Gao Fen-1 (GF-1) Panchromatic and Multi-Spectral (PMS) imagery was used to select training samples and validate the classification results. In this study, all of the land cover types were classified with overall good performance using the proposed method. The results indicated that fully debris-covered glaciers accounted for approximately 20.7% of the total glacier area in this region and were mainly distributed at elevations between 4600 m and 4800 m above sea level (a.s.l.). Additionally, an analysis of the results clearly revealed that the proportion of small size glaciers (< 1 km ² ) were 88.3% distributed at lower elevations compared to larger size glaciers (≥1 km ² ). In addition, the majority of glaciers (both in terms of glacier number and area) were characterized by a mean slope ranging between 20° and 30°, and 42.1% of glaciers had a northeast and north orientation in the Parlung Zangbo basin.

Automatic glacier facies mapping
Landsat
Parlung Zangbo basin
Random Forest

http://resolver.tudelft.nl/uuid:bfbd8bab-1914-49e6-889d-10d680eb2d98

https://doi.org/10.3390/rs11040452

2072-4292

Remote Sensing, 11 (4)

In the Special Issue 'Remote Sensing of Glaciers at Global and Regional Scales'

Institutional Repository

journal article

© 2019 Jingxiao Zhang, Li Jia, M. Menenti, Guangcheng Hu