Annual to seasonal glacier mass balance in High Mountain Asia derived from Pléiades stereo images: examples from the Pamir and the Tibetan Plateau
<p>Glaciers are crucial sources of freshwater in particular for the arid lowlands surrounding High Mountain Asia. To better constrain glacio-hydrological models, annual, or even better, seasonal information about glacier mass changes is highly beneficial. In this study, we evaluate the suitabi...
| Main Authors: | , , , , , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2023-12-01
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| Series: | The Cryosphere |
| Online Access: | https://tc.copernicus.org/articles/17/5435/2023/tc-17-5435-2023.pdf |
| Summary: | <p>Glaciers are crucial sources of freshwater in particular for the arid lowlands surrounding High Mountain Asia. To better constrain glacio-hydrological models, annual, or even better, seasonal information about glacier mass changes is highly beneficial. In this study, we evaluate the suitability of very-high-resolution Pléiades digital elevation models (DEMs) to measure glacier mass balance at annual and seasonal scales in two regions of High Mountain Asia (Muztagh Ata in Eastern Pamirs and parts of western Nyainqêntanglha, south-central Tibetan Plateau), where recent estimates have shown contrasting glacier behaviour. The average annual mass balance in Muztagh Ata between 2019 and 2022 was <span class="inline-formula">−0.07</span> <span class="inline-formula">±</span> 0.20 m w.e. a<span class="inline-formula"><sup>−1</sup></span>, suggesting the continuation of a recent phase of slight mass loss following a prolonged period of balanced mass budgets previously observed. The mean annual mass balance in western Nyainqêntanglha was highly negative for the same period (<span class="inline-formula">−0.60</span> <span class="inline-formula">±</span> 0.15 m w.e. a<span class="inline-formula"><sup>−1</sup></span>), suggesting increased mass loss rates compared to the approximately previous 5 decades. The 2022 winter (<span class="inline-formula">+0.13</span> <span class="inline-formula">±</span> 0.24 m w.e.) and summer (<span class="inline-formula">−0.35</span> <span class="inline-formula">±</span> 0.15 m w.e.) mass budgets in Muztagh Ata and western Nyainqêntanglha (<span class="inline-formula">−0.03</span> <span class="inline-formula">±</span> 0.27 m w.e. in winter; <span class="inline-formula">−0.63</span> <span class="inline-formula">±</span> 0.07 m w.e. in summer) suggest winter- and summer-accumulation-type regimes, respectively. We support our findings by implementing the Sentinel-1-based Glacier Index to identify the firn and wet-snow areas on glaciers and characterize the accumulation type. The good match between the geodetic and Glacier Index results supports the potential of very-high-resolution Pléiades data to monitor mass balance at short timescales and improves our understanding of glacier accumulation regimes across High Mountain Asia.</p> |
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| ISSN: | 1994-0416 1994-0424 |