Channelized Melting Drives Thinning Under a Rapidly Melting Antarctic Ice Shelf

• Published in: Geophysical Research Letters
• Main Authors: Gourmelen, Noel, Goldberg, Dan N., Snow, Kate, Henley, Sian F., Bingham, Robert G., Kimura, Satoshi, Hogg, Anna E., Shepherd, Andrew, Mouginot, Jeremie, Lenaerts, Jan T. M., Ligtenberg, Stefan R. M., van de Berg, Willem Jan
• Other Authors: Institut de physique du globe de Strasbourg (IPGS), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2017
• Subjects: sea level; ice shelves; basal melt; altimetry; thinning; collapse; [SDU]Sciences of the Universe [physics]; Antarctic; West Antarctica; Dotson Ice Shelf; Long Channel; Antarc*; Antarctica; Ice Shelf; Ice Shelves
• Online Access: https://hal-insu.archives-ouvertes.fr/insu-03707642; https://hal-insu.archives-ouvertes.fr/insu-03707642/document; https://hal-insu.archives-ouvertes.fr/insu-03707642/file/Geophysical%20Research%20Letters%20-%202017%20-%20Gourmelen%20-%20Channelized%20Melting%20Drives%20Thinning%20Under%20a%20Rapidly%20Melting%20Antarctic%20Ice.pdf; https://doi.org/10.1002/2017GL074929

International audience Ice shelves play a vital role in regulating loss of grounded ice and in supplying freshwater to coastal seas. However, melt variability within ice shelves is poorly constrained and may be instrumental in driving ice shelf imbalance and collapse. High-resolution altimetry measurements from 2010 to 2016 show that Dotson Ice Shelf (DIS), West Antarctica, thins in response to basal melting focused along a single 5 km-wide and 60 km-long channel extending from the ice shelf's grounding zone to its calving front. If focused thinning continues at present rates, the channel will melt through, and the ice shelf collapse, within 40-50 years, almost two centuries before collapse is projected from the average thinning rate. Our findings provide evidence of basal melt-driven sub-ice shelf channel formation and its potential for accelerating the weakening of ice shelves.