Warming trend threatens iconic Antarctic species

Monday 10th Sep 2012 by theWeather Club

Image: Ted Scambos, NSIDC

A recent study published in the journal Global Change Biology, predicts an uncertain future for the Antarctic Emperor penguin if global warming trends continue. If they do the thinning and shrinking of the Antarctic sea ice could push Emperor penguin toward extinction.

The study led by biologist Stephanie Jenouvrier of the Woods Hole Oceanographic Institution (WHOI) studied a population of Emperor penguins at the coast of Terre Adélie in Antarctica. To project how penguin populations might fare in the future, the researchers used historical sea ice observations, future sea ice predictions, and a demographic model based on half a century's worth of observations of the local penguin populations.

The study found that if temperatures continue to rise at their current rate—causing Antarctic sea ice to shrink—the penguin population of Terre Adélie could respond by declining toward extinction by the year 2100. "Our median projection shows a decline in the number of breeding pairs by 81% over this period, and a good chance (43%) of a more severe decline of 90 % or more," the study shows.

Sea ice, or frozen ocean water, plays an important role in global climate research as it reflects heat back into space and helps balance the heat circulating in the Earth's oceans and atmosphere. Much attention on sea ice has focused on the Arctic Ocean, because it has been declining rapidly in the last several decades. For this study, the researchers focused on the south polar sea ice. Julienne Stroeve of the National Snow and Ice Data Centre who contributed to the study (NSIDC) says, "The Antarctic sea ice has been seeing a slightly positive trend for the last few years. But if the planet continues to warm, we may also have reductions in the Antarctic sea ice and that will surely affect the penguin population."

Emperor penguins breed and raise their young almost exclusively on sea ice. If that ice breaks up and disappears early in the breeding season, massive breeding failure may occur, says Jenouvrier. "As it is, there's a huge mortality rate just at the breeding stages, because only 50% of chicks survive to the end of the breeding season, and then only half of those fledglings survive until the next year".

It means that a drastic reduction in sea either the quality or duration of the sea ice could have dire consequences for this much loves species. Whether this information has arrived in time for us to do something about it, is also unfortunately something that is also open to question.