TY - JOUR
T1 - Interdecadal glacier inventories in the Karakoram since the 1990s
AU - Xie, Fuming
AU - Liu, Shiyin
AU - Gao, Yongpeng
AU - Zhu, Yu
AU - Bolch, Tobias
AU - Kääb, Andreas
AU - Duan, Shimei
AU - Miao, Wenfei
AU - Kang, Jianfang
AU - Zhang, Yaonan
AU - Pan, Xiran
AU - Qin, Caixia
AU - Wu, Kunpeng
AU - Qi, Miaomiao
AU - Zhang, Xianhe
AU - Yi, Ying
AU - Han, Fengze
AU - Yao, Xiaojun
AU - Liu, Qiao
AU - Wang, Xin
AU - Jiang, Zongli
AU - Shangguan, Donghui
AU - ZHANG, Yong-ming
AU - Grünwald, Richard
AU - Adnan, Muhammad
AU - Karki, Jyoti
AU - Saifullah, Muhammad
N1 - Funding Information:
This research has been supported by the International Science and Technology Innovation Cooperation Program of the State Key Research and Development Program (grant no. 2021YFE0116800), the National Natural Science Foundation of China (grant no. 42171129), the Open Foundation from National Cryosphere Desert Data Center (grant no. 2021KF01), the Second Tibetan Plateau Scientific Expedition and Research programme (grant no. 2019QZKK0208), the Pakistan Science Foundation (grant no. PSF/CRP/Consrm-488), the Director Fund of the International Research Center of Big Data for Sustainable Development Goals (grant no. CBAS2022DF020), the Postgraduate Research and Innovation Foundation of Yunnan University (grant no. 2021Z018), and the Scientific Research Fund project of Yunnan Education Department (grant no. 2022Y059).
Publisher Copyright:
© 2023 Fuming Xie et al.
PY - 2023/2/16
Y1 - 2023/2/16
N2 - Multi-temporal glacier inventories provide key information about the glaciers, their characteristics, and changes and are inevitable for glacier modelling and investigating geodetic mass changes. However, to date, no consistent multi-temporal glacier inventory for the whole of the Karakoram exists, negatively affecting the monitoring of spatio-temporal variations in glaciers' geometric parameters and their related applications. We used a semi-automatic method combining automatic segmentation and manual correction and produced a multi-temporal Karakoram glacier inventory (KGI) compiled from Landsat TM/ETM+/OLI (Thematic Mapper, Enhanced Thematic Mapper Plus, and Operational Land Imager) images for the 1990s, 2000s, 2010s, and 2020s. Our assessments using independent multiple digitisation of 37 glaciers show that the KGI is sufficiently accurate, with an overall uncertainty of ±3.68 %. We also performed uncertainty evaluation for the contiguous glacier polygons using a buffer of half a pixel, which resulted in an average mapping uncertainty of ±5.21 %. We calculated more than 20 attributes for each glacier, including coordinates, area, supraglacial debris area, date information, and topographic parameters derived from the ASTER GDEM (Advanced Spaceborne Thermal Emission and Reflection Radiometer global digital elevation model). According to KGI-2020s, approximately 10 500 alpine glaciers (>0.01 km2 each) cover an area of 22510±828 km2 of which 10.18±0.38 % (2290±84 km2) is covered by supraglacial debris. Over the past 3 decades, the glaciers experienced a loss of clean ice and/or snow area but a gain in supraglacial debris. Supraglacial debris cover has increased by 17.63±1.44 % (343.30±27.95 km2), while non-debris-covered glaciers decreased by 1.56±0.24 % (319.85±49.92 km2). The total glacier area was relatively stable and showed only a slight insignificant increase of 23.45±28.85 km2 (0.10±0.13 %). The glacier area has declined by 3.27±0.24 % in the eastern Karakoram, while the glacier area slightly increased in central (0.65±0.10 %) and western Karakoram (1.26±0.11 %). Supraglacial debris has increased over the whole of Karakoram, especially in areas above 4200 m a.s.l. (above sea level), showing an upward shift. The glacier area changes were characterised by strong spatial heterogeneity, influenced by surging and advancing glaciers. However, due to global warming, the glaciers are on average retreating. This is in particular true for small and debris-free glaciers. The multi-temporal KGI data are available at the National Cryosphere Desert Data Center of China: 10.12072/ncdc.glacier.db2386.2022 (F. Xie et al., 2022).
AB - Multi-temporal glacier inventories provide key information about the glaciers, their characteristics, and changes and are inevitable for glacier modelling and investigating geodetic mass changes. However, to date, no consistent multi-temporal glacier inventory for the whole of the Karakoram exists, negatively affecting the monitoring of spatio-temporal variations in glaciers' geometric parameters and their related applications. We used a semi-automatic method combining automatic segmentation and manual correction and produced a multi-temporal Karakoram glacier inventory (KGI) compiled from Landsat TM/ETM+/OLI (Thematic Mapper, Enhanced Thematic Mapper Plus, and Operational Land Imager) images for the 1990s, 2000s, 2010s, and 2020s. Our assessments using independent multiple digitisation of 37 glaciers show that the KGI is sufficiently accurate, with an overall uncertainty of ±3.68 %. We also performed uncertainty evaluation for the contiguous glacier polygons using a buffer of half a pixel, which resulted in an average mapping uncertainty of ±5.21 %. We calculated more than 20 attributes for each glacier, including coordinates, area, supraglacial debris area, date information, and topographic parameters derived from the ASTER GDEM (Advanced Spaceborne Thermal Emission and Reflection Radiometer global digital elevation model). According to KGI-2020s, approximately 10 500 alpine glaciers (>0.01 km2 each) cover an area of 22510±828 km2 of which 10.18±0.38 % (2290±84 km2) is covered by supraglacial debris. Over the past 3 decades, the glaciers experienced a loss of clean ice and/or snow area but a gain in supraglacial debris. Supraglacial debris cover has increased by 17.63±1.44 % (343.30±27.95 km2), while non-debris-covered glaciers decreased by 1.56±0.24 % (319.85±49.92 km2). The total glacier area was relatively stable and showed only a slight insignificant increase of 23.45±28.85 km2 (0.10±0.13 %). The glacier area has declined by 3.27±0.24 % in the eastern Karakoram, while the glacier area slightly increased in central (0.65±0.10 %) and western Karakoram (1.26±0.11 %). Supraglacial debris has increased over the whole of Karakoram, especially in areas above 4200 m a.s.l. (above sea level), showing an upward shift. The glacier area changes were characterised by strong spatial heterogeneity, influenced by surging and advancing glaciers. However, due to global warming, the glaciers are on average retreating. This is in particular true for small and debris-free glaciers. The multi-temporal KGI data are available at the National Cryosphere Desert Data Center of China: 10.12072/ncdc.glacier.db2386.2022 (F. Xie et al., 2022).
UR - http://www.scopus.com/inward/record.url?scp=85148727025&partnerID=8YFLogxK
U2 - 10.5194/essd-15-847-2023
DO - 10.5194/essd-15-847-2023
M3 - Article
AN - SCOPUS:85148727025
SN - 1866-3508
VL - 15
SP - 847
EP - 867
JO - Earth System Science Data
JF - Earth System Science Data
IS - 2
ER -