Glacier Fragmentation on the Southern Patagonian Icefield: A Comprehensive Analysis of the Upsala Glacier Case

LO VECCHIO ANDRÉS; VILLALBA, RICARDO; FALASCHI, DANIEL; RUIZ, LUCAS; VACAFLOR PAULINA; VARGAS, SOFIA

JOURNAL OF GLACIOLOGY

INT GLACIOL SOC

Lugar: London; Año: 2024

0022-1430

Glacier fragmentation is a common result of the global recession of calving glaciers. This process involves a glacier trunk detaching and splitting into smaller units, which significantly impacts glacier dynamics. As a result, there is rapid terminus retreat and increased surface velocity. The Southern Patagonian Icefield (SPI), which is the largest glacial extent in the Southern Hemisphere after Antarctica, has experienced at least 11 glacier fragmentations since 1980. However, the impact of fragmentation on SPI glaciers is still uncertain. The fragmentation of Upsala glacier from 2011 to 2022 provided an opportunity for evaluation. The analysis of 101 Sentinel-1A SAR images revealed that the tributary glacier (Bertacchi) acted as a lateral pinning point for the main glacier flow (Western). After the fragmentation, the absence of this support caused a rapid increase in the glacier´s retreat rate from 6 to 279 ma -1. In contrast, the main glacier remained stable when connected, even at high velocities (greater than 3 md-1). Fragmentation of the SPI glacier in the future may increase mass loss from the icefield.