Black carbon pollution from tourism and research activities in Antarctica Ice melt on the continent is likely to increase by about 83 tons per visitor, according to new research.

Scientists have estimated that the black carbon produced by ships, planes and diesel generators leads to an additional 23 mm of snow melt each summer in the most visited areas of land covered in ice.

More than 74,000 tourists visited Antarctica in 2019-2020 seasonnearly double the numbers of ten years ago.

A team of researchers sampled snow annually between 2016 and 2020 at 28 sites stretching 2,000 kilometers from the northern tip of Antarctica to the Ellsworth Mountains.

They focused primarily on the Antarctic Peninsula, where about half of the research facilities on the continent are located and where an estimated 95% of Antarctic tours are conducted.

The team estimated that 53,000 tourists visited Antarctica annually between 2016 and 2020.

Study co-author Dr. Raul Cordero, from the University of Santiago in Chile, said Antarctic snows were the cleanest on Earth, with base levels of black carbon typically around one part per billion.

“That’s 1,000 times less than what you can find in the Himalayas, and 100 times less than what you can find in the Andes or the Rockies,” he said.

Black carbon levels were two to four times higher at sites on the Antarctic Peninsula than in other parts of the continent.

What the black carbon does is make the snow darker [so it] “It absorbs more solar radiation,” Cordero said. “This extra energy speeds up the melting of the ice.”

It is believed that a limit on the number of tourists to Antarctica may need to be introduced.

The team quantified the potential melting of snow by calculating how black carbon pollution has reduced snow whiteness – a measure of how well the surface reflects solar energy.

They calculated that the black carbon footprint of an Antarctic researcher was about 10 times larger than that of a tourist.

“We estimated that … the snow that melts faster due to the researcher’s activities would be closer to 1,000 tons,” Cordero said. “Every researcher uses ships, planes, helicopters, generators – and everyone uses diesel to power these.”

Cordero said that while the amount of snowmelt from pollution is much less than the ice and snow lost due to global warming, the study highlights the need to move to renewable energy sources.

“There are technical alternatives to diesel that can be used in Antarctica,” he said, citing the Belgian research station, Princess Elizabeth of Antarcticawhich is mainly driven by wind.

Professor Andrew McIntosh, chair of the School of Atmosphere and Environment at Monash University, who was not involved in the research, said the link between Carbon black pollution and increased surface solubility It was well established in other parts of the world.

“On the Antarctic Peninsula, the two main processes [affecting melting] Warming oceans would still be melting ice layers from below, or warming surface air temperatures that are melting ice from above,” McIntosh said.

“If we have a greater surface temperature rise [the] Decades to centuries to come, as predicted for the Antarctic Peninsula, the extra black carbon at the surface will cause more melt than otherwise would have occurred.”

“Human activity is causing the polar regions to warm, but burning… [fossil] The fuel has a direct consequence in terms of surface melting as well.”

“If you can get rid of greenhouse gases in the first place, you will reduce the temperature rise,” he said. “There is also the added benefit of reducing the opacity of ice surfaces.”

“Antarctica is the last fairly unpolluted continent,” Cordero said. “I think we should try to keep it that way.”

The study was published in the peer-reviewed journal Nature Communications.