Antarctica's mineral riches exposed as climate warms

Prospectors are scouring the Pacific Ocean seafloor and Greenland's vast landscape for valuable minerals to run the world's economy. Should Antarctica be added to the treasure hunters' list?

A new study finds that, as the climate continues to warm over the next decades, tens of thousands of square miles of Antarctica will lose their protective covering of ice, exposing valuable deposits of copper, iron, gold, silver, platinum and cobalt.

Geologists have been exploring the frozen continent for more than a century, and climate scientists now have a better idea about which parts of Antarctica might be easier to access in the future. Nearly all of the continent is covered by either ice sheets or glaciers; however, some regions of Antarctica are warming twice as fast as the global average.

"We are projecting how much ice-free land is going to emerge, and the relation of that ice-free land to the known mineral occurrences," said Erica Lucas, a postdoctoral researcher at the University of California, Santa Cruz and an author of a study published last week in Nature Climate Change.

An international treaty bans mining in Antarctica; however, nations can propose changes beginning in 2048. Lucas said that the study could help guide decisions about possible mining locations after that date.

Less than 0.6% of Antarctica is estimated to be free of ice cover, including coastlines, mountain ranges, valleys and cliffs. Global warming, driven by the burning of fossil fuels, is changing that. Antarctic ice and glaciers have undergone rapid thinning and retreat over the past few decades, and that will continue, the study said.

"We made these projections because we want to better understand if there's going to be future calls for mineral resource development," Lucas said.

Two regions of Antarctica hold the most promising mineral deposits: the 810-mile-long Antarctic Peninsula, which sticks up from the continent like a thumb toward the southern tip of South America; and the 2,000-mile-long Transantarctic Mountains that separate East and West Antarctica.

The peninsula is claimed by Chile, Argentina and the United Kingdom, and the mountain range is claimed by Australia and New Zealand. All territorial claims on Antarctica were suspended by the 1959 Antarctic Treaty and are not recognized by other nations.

However, the study's authors predict that as more land is exposed, countries will begin to advocate mining.

The study examined several future scenarios to determine how much land would become free from ice, weighing global temperatures, rising sea levels along the coast and how much the land could rise once the ice melts and the weight of glaciers is removed.

Under a moderate ice-melting scenario, about 14,000 square miles of Antarctica would be exposed by the year 2300, a figure that increases to about 46,600 square miles under a high ice-melting scenario.

The amount of ice that retreats depends on future greenhouse gas emissions, Lucas said. But she cautioned that there was uncertainty in some projections of ice melting beyond 2100.

Average global temperatures are predicted to rise by 2.6 degrees Celsius (4.7 degrees Fahrenheit) above preindustrial levels by 2100, according to Climate Action Tracker, a research group.

The authors examined existing studies of mineral deposits and regions where, 180 million years ago, Antarctica was connected to Australia, Africa and South America as part of the supercontinent Gondwana.

"We know that all of the other continents that bordered Antarctica during this time period have large mineral deposits," Lucas said. "Because Antarctica is geologically similar to those continents, we can assume that there is likely also similar mineral deposits in Antarctica."

Rising global temperatures and retreating ice sheets would expose between 12 million and 25 million metric tons of copper deposits on the Antarctic Peninsula, according to the study.

Global copper demand is at 28 million metric tons and is expected to jump to 42 million metric tons by 2040 as demand for electricity grows, according to a January report by S&P Global, a financial analytics firm based in New York.

Tony Press, adjunct professor at the Institute for Marine and Antarctic Studies at the University of Tasmania, said the methodology of the new study was "really interesting, and there's going to be new areas of bare ground, which may or may not provide places for people to explore for minerals."

Press also cautioned that prospecting for minerals on a continent without seaports or roads would be difficult.

In the Arctic, for example, commercial mining requires cold weather to move mining vehicles across the land and over rivers, according to Press. "Climate change is going to change that, but you can't actually predict how that's going to be at the moment," he said.

Press also noted that global warming was causing more icebergs to break off from glaciers along the Antarctic coast, making the Southern Ocean more hazardous for ships.

For now, Antarctica is protected from commercial development and open only to scientists and tourists.

"There will be less ice, and therefore, some opportunities, but Antarctica is a very remote place," said Evan Bloom, former head of Antarctic diplomacy at the U.S. State Department and a senior fellow at the German Marshall Fund.