Landsat- and Sentinel-derived glacial lake dataset in the China–Pakistan Economic Corridor from 1990 to 2020
<p>The China–Pakistan Economic Corridor (CPEC) is one of the flagship projects of the One Belt One Road Initiative, which faces threats from water shortage and mountain disasters in the high-elevation region, such as glacial lake outburst floods (GLOFs). An up-to-date high-quality glacial lake...
| Main Authors: | , , , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2022-12-01
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| Series: | Earth System Science Data |
| Online Access: | https://essd.copernicus.org/articles/14/5489/2022/essd-14-5489-2022.pdf |
| Summary: | <p>The China–Pakistan Economic Corridor (CPEC) is one of the flagship
projects of the One Belt One Road Initiative, which faces threats from water
shortage and mountain disasters in the high-elevation region, such as
glacial lake outburst floods (GLOFs). An up-to-date high-quality glacial
lake dataset with parameters such as lake area, volume, and type, which is
fundamental to water resource and flood risk assessments and prediction of
glacier–lake evolutions, is still largely absent for the entire CPEC. This
study describes a glacial lake dataset for the CPEC using a threshold-based
mapping method associated with rigorous visual inspection workflows. This
dataset includes (1) multi-temporal inventories for 1990, 2000, and 2020
produced from 30 m resolution Landsat images and (2) a glacial lake
inventory for the year 2020 at 10 m resolution produced from Sentinel-2
images. The results show that, in 2020, 2234 lakes were derived from the
Landsat images, covering a total area of <span class="inline-formula">86.31±14.98</span> km<span class="inline-formula"><sup>2</sup></span> with a
minimum mapping unit (MMU) of 5 pixels (4500 m<span class="inline-formula"><sup>2</sup></span>), whereas 7560 glacial lakes
were derived from the Sentinel-2 images with a total area of <span class="inline-formula">103.70±8.45</span> km<span class="inline-formula"><sup>2</sup></span> with an MMU of 5 pixels (500 m<span class="inline-formula"><sup>2</sup></span>). The
discrepancy shows that Sentinel-2 can detect a large quantity of
smaller lakes compared to Landsat due to its finer spatial resolution.</p>
<p>Glacial lake data in 2020 were validated by Google Earth-derived lake
boundaries with a median (<span class="inline-formula">±</span> standard deviation) difference of
<span class="inline-formula">7.66±4.96</span> % for the Landsat-derived product and <span class="inline-formula">4.46±4.62</span> %
for the Sentinel-derived product. The total number and area of glacial lakes
from consistent 30 m resolution Landsat images remain relatively stable
despite a slight increase from 1990 to 2020. A range of critical attributes
has been generated in the dataset, including lake types and mapping
uncertainty estimated by an improved equation of Hanshaw and Bookhagen (2014). This comprehensive
glacial lake dataset has the potential to be widely applied in studies on
water resource assessment, glacial lake-related hazards, and glacier–lake
interactions and is freely available at
<a href="https://doi.org/10.12380/Glaci.msdc.000001">https://doi.org/10.12380/Glaci.msdc.000001</a> (Lesi et al., 2022).</p> |
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| ISSN: | 1866-3508 1866-3516 |