文章基本信息

标题：Recent ice dynamics and mass balance of Jorge Montt Glacier, Southern Patagonia Icefield
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作者：Francisca Bown ; Andrés Rivera ; Michał Pętlicki 等
期刊名称：Journal of Glaciology
印刷版ISSN：0022-1430
电子版ISSN：1727-5652
出版年度：2019
卷号：65
期号：253
页码：732-744
DOI：10.1017/jog.2019.47
出版社：Cambridge University Press
摘要：The Southern Patagonia Icefield (SPI) withdrawal in recent decades shows contrasting behaviours between adjacent basins. One of the basins with highest volumetric losses is located at northernmost SPI. We refer to Jorge Montt tidewater glacier (48 ° 30′S/73 ° 30′W, 445 km 2 in 2018), which retreated 2.7 km between 2011 and 2018 and thinned at rates of up to 21 m a −1 over this period. Based on the retreat record, remote-sensing imagery, field data, a mass-balance model and a calving parameterisation, we attempted to differentiate climatic-induced changes (i.e. surface mass balance) and dynamic responses (i.e. calving fluxes). The surface mass balance reached −4.15 km 3 w.e. a −1 between 2012 and 2017. When frontal ablation is included, the net mass balance is −17.79 km 3 w.e. a −1 . This represents a change of trend compared with modelling estimations of positive surface mass balance prior to 2010. This shift is attributed to higher ablation rates given that accumulation is known to have increased between 1980 and 2015. The available evidence, therefore, indicates that frontal ablation is the main factor, supported by observed rates at Jorge Montt as high as 3.81 km 3 w.e. a −1 in 2015, with ice velocities peaking at 11 km a −1 .
关键词：Glacier calving; glacier mass balance; ice velocity