Antarctica’s Future is Heating Up

Antarctica’s Ross Sea is projected to lose half its summer sea ice by 2050 according to a study lead by Walker Smith, professor at the Virginia Institute of Marine Science. These changes will impact the marine life in what is one of the world’s most productive and unspoiled marine ecosystems, where rich blooms of phytoplankton feed krill, fish, and higher predators such as whales, penguins, and seals, says Smith.

In the February 26 issue of Geophysical Research Letters, Smith and colleagues reported their observation of air and water temperatures, changes in wind speed, precipitation, salinity and ocean currents. They predicted that air temperatures would rise due to the ocean currents and wind direction. Their model demonstrated a drastic reduction in extent and duration of sea ice.

The modeled summer sea ice concentrations decreased by 56% by 2050 and 78% by 2100. The season without ice increased which would cause a drop in ice cover that will negatively affect  species that are ice-dependent including crystal krill and Antarctic silverfish. These krill are a major food source for top predators such as minke whales, Emperor penguins, and seals.

Changes in Ross Sea ice will impact the marine life such as these Emperor Penguins who rely on this sea ice for shelter and food.

 

The Ross Sea is important in regulating the Antarctic sea ice and supporting an abundance of planktonic life which in turn provides food for larger species. Scientists conclude that the annual phytoplankton production in the future will increase while other components of the food web will be disrupted creating significant impacts on the ecosystem. 

 

 

Sources:

  1. Walker O. Smith, Michael S. Dinniman, Eileen E. Hofmann, John M. Klinck. The effects of changing winds and temperatures on the oceanography of the Ross Sea in the 21stcenturyGeophysical Research Letters, 2014; DOI:10.1002/2014GL059311
  2. Virginia Institute of Marine Science. “Big thaw projected for Antarctic sea ice: Ross Sea will reverse current trend, be largely ice free in summer by 2100.” ScienceDaily. ScienceDaily, 27 February 2014. <www.sciencedaily.com/releases/2014/02/140227115512.htm>.

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