Sivalingam Sivaranjani, Murugesan Geetha Priya, Kulkarni Anil Vishnupant, Dhulipala Krishnaveni, Devaraj Suresh
Centre for Incubation, Innovation, Research and Consultancy-Jyothy Institute of Technology, Bengaluru, 560082, India.
Divecha Centre for Climate Change, Indian Institute of Science, Bengaluru, 560012, India.
Environ Sci Pollut Res Int. 2023 May;30(22):62782-62802. doi: 10.1007/s11356-023-26441-3. Epub 2023 Mar 22.
Glaciers in the Karakoram region are widely recognized for their historical surging phenomenon. Accurate field-based glacier monitoring is challenging in the Karakoram due to the presence of mixed-nature glaciers that are advancing, receding, and surging. Many geographers came to the opinion that surging is a thermally controlled activity in the Karakoram as opposed to a hydrologically controlled activity as a result of characteristics including high-altitude warmth, precipitation, and accumulation patterns of these glaciers. But the main surge mechanism is still a mystery. The current study used Landsat multispectral satellite datasets to examine and investigate the glaciers' vulnerability to surging activity in the Hunza basin based on the annual surface ice flow rate and frontal snout advancement of the glaciers from 1990 to 2021. Around 80 glaciers in the Hunza basin have been researched, and based on interannual surface flow rates, it has been determined that Batura, Hassanabad II, Barpu, Gharesa, Hispar, Khurdopin, Minapin, Virjerab, Yazgil, and Ghulkin glaciers are more vulnerable to surging. The findings show that during the research period, these glaciers had surged and advanced along their snouts. The frontal snout of these glaciers advances, and moraines are deposited closer to the glacier terminus as a consequence of active surge points over the ablation region. The Hunza basin's topography, precipitation, and thermal regimes regulate the glaciers' surging phenomena causing successive acceleration in the glaciers. Field-based measurements made with a differential global positioning system are used to corroborate the obtained results.
喀喇昆仑地区的冰川因其历史上的跃动现象而广为人知。由于存在前进、后退和跃动的混合性质冰川,在喀喇昆仑进行基于实地的精确冰川监测具有挑战性。许多地理学家认为,由于这些冰川具有高海拔温暖、降水和积累模式等特征,跃动在喀喇昆仑是一种受热力控制的活动,而非受水文控制的活动。但主要的跃动机理仍是个谜。本研究使用陆地卫星多光谱卫星数据集,基于1990年至2021年冰川的年表面冰流速率和冰舌前端推进情况,研究和调查了罕萨河流域冰川对跃动活动的脆弱性。对罕萨河流域约80条冰川进行了研究,根据年际表面流速,已确定巴图拉、哈桑阿巴德二号、巴尔普、加雷萨、希斯帕尔、胡尔多平、米纳平、维尔杰拉布、亚兹吉尔和古尔金冰川更容易发生跃动。研究结果表明,在研究期间,这些冰川发生了跃动并沿着冰舌向前推进。由于消融区活跃的跃动点,这些冰川的冰舌前端向前推进,冰碛物沉积在更靠近冰川末端的地方。罕萨河流域的地形、降水和热力状况调节着冰川的跃动现象,导致冰川相继加速。使用差分全球定位系统进行的实地测量用于证实所得结果。