Ocean access to a cavity beneath Totten Glacier in East Antarctica

Caroline Dougherty

Recently published research from scientists at the University of Texas at Austin reveals that Totten Glacier in East Antarctica might melt more quickly than previously predicted. If the glacier melts in its entirety, it contains enough ice to raise global sea levels by 3.4 meters, or 11 feet. Scientists have previously observed that warm waters on the seaward side of the glacier might be responsible for the majority of ice melt. The University of Texas scientists used laser surface altimetry and ice-sounding radar and magnometers, among other technologies, to assemble exhaustive data about the glacier’s interactions with warm sea waters.

Using the new data scientists were able to identify a previously unknown inland trough that connects the main ice-shelf of the glacier to the ocean. Scientists also identified entrances to the ice-shelf cavity below depths of 400-500 m that could allow intrusions of warm water. Water at deeper levels of the ocean is usually colder than water near the surface of the ocean—but if warmer waters are saltier than cold waters, the warm water can sink, allowing it to enter ice shelves at extreme depths. The recent research by Greenbaum et al. reveals that glaciers in East Antarctica are facing the dangerous melting processes that were thought to be limited to West Antarctica.

As global temperatures rise, warm sea waters will accelerate arctic and antarctic ice melt. It may take centuries for Totten Glacier to melt, but its melting will probably be irreversible. Melting sea ice will lead to rising sea levels, which will surely have vast and largely unknown impacts on complicated earth systems and coastal communities.

 

 

Greenbaum, J. S., Blankenship, D. D., Young, D. A., Richter, T. G., Roberts, J. L., Aitken, A. R. A., & Siegert, M. J. (2015). Ocean access to a cavity beneath Totten Glacier in East Antarctica. Nature Geoscience.