Antarctica Is Dumping Hundreds of Gigatons of Ice into the Ocean Right Now
The southern, frozen continent lost an average of 252 gigatons of ice a year to the sea between 2009 and 2017. Between 1979 and 1990, it lost an average of just 40 gigatons per year. That means that ice loss on Antarctica has accelerated by 6.3 times in just four decades, according to new research published Jan. 14 in the journal Proceedings of the National Academy of Sciences.
As the sea ice at the North Pole melts away, the melting causes negative consequences and ripple effects for the global climate. However, that melting doesn’t directly raise sea levels. North polar ice is already floating on the ocean, so turning it from solid to liquid doesn’t add to the total volume of water in the seas, according to NASA.
But Antarctica is a landmass buried beneath ice. And it holds the largest reserve of frozen, landlocked water anywhere on the planet. Any ice loss on Antarctica directly contributes to the total volume of water in the oceans, and raises sea levels.
Hidden Beneath a Half Mile of Ice, Antarctic Lake Teems with Life
The dark waters of a lake deep beneath the West Antarctic ice sheet and a few hundred miles from the South Pole are teeming with bacterial life, say scientists — despite it being one of the most extreme environments on Earth.
The discovery has implications for the search for life on other planets — in particular on the planet Mars, where signs of a buried lake of liquid saltwater were seen in data reported last year by the European Space Agency’s orbiting Mars Express spacecraft.
The drill team bored through about 3,504 feet (1,068 meters) of ice, and the water below was a chilly 30.8 degrees Fahrenheit (minus 0.65 degrees Celsius), so that scientific researchers could take water samples and sediment cores from the lake, which was about 49 feet (15 m) deep at that spot and covers an area of about 54 square miles (139 square kilometers) under the ice sheet.
Early studies of water samples taken from Lake Mercer — which is buried beneath a glacier — showed that they contained approximately 10,000 bacterial cells per milliliter. That’s only about 1 percent of the 1 million microbial cells per milliliter typically found in the open ocean, but a very high level for a sunless body of water buried deep beneath an Antarctic glacier.
The scientists said that the high levels of bacterial life in the dark and deeply buried lake were signs that it might support higher life-forms, such as microscopic animals like tardigrades.
Upper-ocean warming is making waves stronger
Sea level rise puts coastal areas at the forefront of the impacts of climate change, but new research shows they face other climate-related threats as well. Scientists found that the energy of ocean waves has been growing globally, and they found a direct association between ocean warming and the increase in wave energy.
The new study focused on the energy contained in ocean waves, which is transmitted from the wind and transformed into wave motion. This metric, called wave power, has been increasing in direct association with historical warming of the ocean surface. The upper ocean warming, measured as a rising trend in sea-surface temperatures, has influenced wind patterns globally, and this, in turn, is making ocean waves stronger.