Climate fears are mounting as scientists question whether Antarctica has reached a ‘point of no return’

About 1,500 academics, researchers and scientists specializing in Antarctica gathered in southern Chile at the 11th meeting of the Scientific Committee for Antarctic Research this week to share the most impressive research from the great white continent.

Almost all aspects of science, from geology to biology and glaciology to art, were covered but the main conference was held under the umbrella of the conference. Antarctica is changing, faster than expected.

Extreme weather events in the ice-covered continent were no longer hypothetical presentations, but the first accounts from researchers about heavy rain, intense heat waves and rapid Foehn events (strong dry winds) at research stations led to massive melting, massive ice breaks. -climate and hazardous conditions with global impacts.

With weather station data and satellite data going back only about 40 years, scientists wondered if these events meant Antarctica had reached a limit, or a tipping point for rapid and irreversible sea ice loss from the West Antarctic ice sheet.

“There is uncertainty about whether these observations now indicate a temporary subsidence or subsidence (of sea ice),” said Liz Keller, a paleoclimate expert from Victoria University of Wellington in New Zealand who led a session on forecasting and key points. Antarctica.

NASA estimates show that the Antarctic ice sheet contains enough ice to raise global sea levels up to 58 meters. Studies have shown that almost one-third of the world’s population lives less than 100 vertical meters from the sea.

Although it is difficult to determine whether we have reached the “point of no return,” Keller says it is clear that the rate of change is unprecedented.

“You can see the same increase in CO2 over thousands of years, and now it’s happened over 100 years,” Keller said.

Mike Weber, a paleoceanographer at the University of Bonn in Germany, who specializes in Antarctic ice stability, says sediment records going back 21,000 years show similar periods of rapid ice melting.

The ice sheet has experienced similar rapid ice loss at least eight times, Weber said, with accelerations beginning in a few decades leading to ice loss that can last for centuries, leading to higher global sea levels.

Weber says that ice loss has increased over the past decade, and the question is whether or not a phase lasting centuries has begun.

“We’re probably entering a phase like that right now,” Weber said. “If we are there, at least for now, there will be no stopping.”

Keeping output low

While some say climate change has been shut down, scientists have agreed that worst-case scenarios can still be avoided by drastically reducing fossil fuel emissions.

Weber says that the earth’s crust is moving back due to the retreat of glaciers and their decreasing weight can balance the rise in sea levels, and new research published in recent weeks shows that balance can still be achieved if the rate of change is slow enough.

“If we keep emissions down, we can stop this eventually,” Weber said. “If we keep them up, we’re in a run situation and there’s nothing we can do.”

Mathieu Casado, a tropical and polar meteorologist at France’s Climate and Environment Sciences Laboratory, specializes in studying water isotopes to reconstruct historical temperatures.

Casado said data from dozens of ice cores collected from across the ice sheet allowed him to reconstruct temperature patterns in Antarctica dating back 800,000 years.

Casado’s research showed that the current increase in temperature over the past fifty years was clearly outside of natural variability, highlighting the role of industry in producing carbon emissions that drive climate change.

He added that the last time the Earth was this warm was 125,000 years ago and sea levels were 6 to 9 meters higher “with little effect on West Antarctica.”

Temperature and carbon dioxide have historically been balanced and balanced, Casado said, but currently we have very high levels of CO2 and are far from balanced.

Casado and other scientists noted that the speed and amount of carbon being pumped into the atmosphere is unprecedented.

Gino Casassa, glaciologist and head of the Chilean Antarctic Institute, said current estimates show sea levels rising by 4 meters by 2100 and more if emissions continue to increase.

“What happens in Antarctica doesn’t stay in Antarctica,” said Casassa, adding that the world’s atmosphere, oceans and climate are connected to the continent.

“Antarctica is not just a frozen glacier isolated from the rest of the world.”

– Alexander Villegas, Reuters