A study that raises new concerns about sea-level rise found that two seafloor gateways or "troughs" could allow warm ocean water to reach the very base of the Totten Glacier in East Antarctica. Research about the findings was published March 16 in Nature Geoscience. Here is the rundown:

    Totten Glacier: Totten Glacier's ice shelf is approximately 93 miles (150 kilometers) long and 18 miles (30 kilometers) wide. It is described by NASA as East Antarctica’s largest and most rapidly thinning glacier.

    The research: Data was collected during five Antarctic field campaigns using aircraft equipped to analyze the ice and seafloor in regions that even icebreakers are unable to reach, according to the University of Texas.  
    Scientists from around the world took part in the research, including the University of Texas Institute for Geophysics, the ICECAP (International Collaboration for Exploration of the Cryosphere through Aerogeophysical Profiling) project, NASA and scientists in Europe and Australia.

    What they found: Warm ocean water could reach the glacier's base through two "seafloor gateways," according to the University of Texas.
    Scientists don’t know how long it will take for the Totten Glacier to collapse, and research on that question is ongoing.  As it is, the Intergovernmental Panel on Climate Change has predicted that the global sea level will rise 7 to 23 inches by 2100 -- but the panel admitted that this prediction did not account for melting ice sheets, according to the National Oceanic and Atmospheric Administration. 

    Why it matters: Totten Glacier drains enough ice from the East Antarctic Ice Sheet to raise global sea levels by about 11 feet (3.5 meters), scientists say. This new research helps scientists understand why the glacier is thinning. It also raises questions about how this will affect sea level rise. A researcher from Imperial College London said that destabilization of Totten Glacier could make ice inland vulnerable as well.   

    Is it irreversible? It may soon be, according to the University of Texas, “unless atmospheric and oceanic conditions change so that snowfall outpaces coastal melting."

     This story was compiled using information from these sources:

• University of Texas at Austin: East Antarctica Melting could be explained by oceanic gateways.
• Imperial College London: Warm ocean water is making Antarctic glacier vulnerable to significant melting
• Nature Geoscience: Ocean access to a cavity beneath Totten Glacier in East Antarctica  
  
• Climate.gov--The National Oceanic and Atmospheric Administration: Climate change, global sea level  
• NASA: University of Texas-NASA study sees new threat to East Antarctic ice

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