Warm Ocean Water Accelerating Melt Rate of Langhovde Ice Shelf in East Antarctica

Nature Communications, July 9

The Langhovde ice shelf, 3 km wide is a relatively (for Antarctica) small ice shelf on East Antarctica. Measurements found that the ocean water underneath Langhovde ice shelf is warmer than the in situ freezing point of water by around half a degree or a degree, depending on the season. This is resulting in an average melt rate of about 1.5 meters annually, despite the relatively colder temperatures in East Antarctica as compared to West Antarctica. When deep ocean water flows through troughs in the seafloor, it can mix with warmer water and rise into the cavity beneath the ice shelf. Melting along the entire base of the ice shelf occurs when this cavity is filled with this warmer water, which increasingly appears to be happening year-round underneath the Langhove ice shelf. Currently, such basal melt from ice shelves is the principal driver of ice loss in Antarctica, both through discharge of ice and especially in future, loss of the buttressing effect of ice shelves on the main ice sheet. The circulation of water plays a pivotal role in the vulnerability of ice shelves as oceanic warming accelerates their melting and ice loss.