Ice-Free Antarctica: Climate Change Could Devastate Continent's Wildlife as Dry Areas Grow

Adélie penguin at Lovill Bluff Colony, Mount Siple, West Antarctica. Plants and animals are under threat on the frozen continent. Jasmine Lee/Australian Antarctic Division

Think of Antarctica and, basically, you think of ice, right?

Fair enough: More than 99 percent of the continent is covered in it. But some of it isn't, and a study published in Nature on Thursday says those bits could be about to increase, with worrying effects for the frozen continent's ecosystem.

The study, led by University of Queensland School of Biological Sciences Ph.D. student Jasmine Lee, looks at the likely impact of climate change on the small scraps of Antarctica not covered by ice.

Lee found that, as ice melted, these areas could expand by more than 17,000 square kilometers by the end of the century—a 25 percent increase—under the most dramatic scenario.

These ice-free areas are home to virtually all of the continent's wildlife, including some species found nowhere else in the world. The Mopsechiniscus franciscae, for example, is a type of tardigrade (tiny micro animals that are known adorably in some parts of the world as moss piglets) recorded only in the Victoria Land area of Antarctica.

And, the study warns, a dramatic growth in ice-free land will mean formerly separate ice-free areas merging, while warmer temperatures signify conditions will be more favorable for invasive species that might drive out rare specimens.

While conceding that it is difficult to predict the precise impact of the changes, the study warns that long-term effects could include a less diverse ecosystem and the extinction of some species that find themselves unable to compete in their new environment.

"Ice-free areas make for small patches of suitable habitat for plants and animals—like islands in a sea of ice," Lee said. "These areas are home to the majority of Antarctic species—from seals and seabirds to mosses, lichens and small invertebrates, such as tardigrades and springtails. This expansion of ice-free habitat could lead to new opportunities for Antarctic biodiversity, although the warmer conditions will also encourage invasive species to establish," Lee continued.

"Many native species have evolved isolated from each other for extended time periods; they are mainly constrained by the availability of resources, such as water and nutrients.

"How they will cope with increasing connectivity and competition from invasive species is largely unknown."

The study concludes that if emissions can be reduced, the impact on the ice-free parts of Antarctica could be lessened. "This [study] highlights the need for continued monitoring and modeling of Antarctic ecosystems as climate change progresses and longer-term projections become available," the study says.

"Although global emissions are currently tracking the highest greenhouse gas emissions scenario, if emissions can be reduced, and anthropogenic temperature increases kept to below 2 degrees Celsius, (as per the Paris Agreement), then the impacts on ice-free habitat and its dependent biodiversity are likely to be reduced."