New Study Finds Alaskan Glacier Positioned to be a Big Contributor to Sea-Level Rise
As reported by Alaska Beacon on May 02, a new study published in the Journal of Geophysical Research Earth Surface found two-thirds of the Malaspina Glacier is grounded below sea level. Low frequency airborne radar equipment was used to measure the glacier’s volume between 2009 and 2021 as part of NASA’s Operation IceBridge program. The study found that the low elevation renders the Alaskan glacier more susceptible to melting, which could significantly contribute to a rise in global sea levels. (Alaska Beacon)
The study explained
Primarily located in the Wrangell-St. Elias National Park and Preserve, the Malaspina Glacier is the world’s largest piedmont glacier (a valley glacier which spills out of the mountains, into a broad coastal basin). The recent study, led by University of Arizona scientists analyzed data gathered by airborne radar sounding, finding two-thirds of the glacier is grounded below sea level and is undercut by several subglacial channels. Researchers concluded that the continued erosion of the narrow ice-cored coastal barrier, due to rising global temperatures, may provide a pathway for ocean waters to access large areas of the glacier's bed along its subglacial channels. Ice-ocean connection will result in large-scale calving and the glacier's retreat. Estimates project the Malaspina Glacier has the potential to contribute up to 1.4 mm to global sea-level rise. The study’s lead, geophysics doctoral student Brandon Tober, hopes further ongoing research forecasting the rate of the glacier’s retreat will be ready for release by the end of the year.
Rising sea-levels have a disproportionate impact on the livelihoods and critical infrastructure of Arctic coastal communities. Climate driven coastal flooding and erosion has recently caused significant damage in areas such as the Hay River in the Northwest Territories and Kivalina, an Alaskan barrier island. Consequently, accurate and consistent monitoring of glaciers is an important activity within wider climate and flood mitigation measures. (Alaska Beacon, CBC News, Greenpeace, JGR Earth Surface, The Conversation)