Antarctica warming faster than predicted; alarming for sea levels

By Al Mayadeen English
Source: News websites
8 Sep 2023 09:41
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A warming Antarctic could lead to further losses of sea ice, impacting ocean warming, global ocean circulation, and marine ecosystems, a new study warns.

Adelie penguins in Antarctica (AFP)

A scientific study indicates that Antarctica is experiencing warming at a rate nearly double that of the rest of the world and faster than what climate change models have predicted. This accelerated warming has the potential for significant implications in terms of global sea level rise.

Researchers examined 78 Antarctic ice cores to reconstruct temperature trends over the past millennium and discovered that the warming observed across the continent exceeds what could be attributed to natural climate variations.

In West Antarctica, an area recognized as particularly susceptible to warming and whose ice sheet could significantly contribute to rising global sea levels if it were to collapse, the study revealed a warming rate twice as rapid as what climate models had anticipated.

Climate scientists had long anticipated that polar regions would experience more rapid warming compared to the rest of the planet, a phenomenon known as polar amplification, which has already been observed in the Arctic.

Deeply concerning: Significant warming in Antarctica revealed

Dr. Mathieu Casado, the lead author of the study and a researcher at the Laboratoire des Sciences du Climat et de l'Environnement in France, emphasized that their findings provide "direct evidence" of Antarctica undergoing polar amplification. This phenomenon, which entails more rapid warming in polar regions compared to the rest of the world, has now been confirmed in Antarctica.

The study's results are deeply concerning, as they reveal significant warming in Antarctica that exceeds what could be attributed to natural climate variations. Antarctica, a landmass equivalent in size to the continental US and Mexico combined, has only 23 permanent weather stations, with just three of them situated inland away from the coast.

Casado and his colleagues conducted their research by analyzing 78 Antarctic ice cores, which provide a historical record of temperature. They then compared these temperature records to climate models and real-world observations. Their study, published in the journal Nature Climate Change, disclosed that Antarctica is warming at a rate ranging from 0.22°C to 0.32°C per decade, surpassing the 0.18°C per decade predicted by climate models.

Part of the warming in Antarctica may be obscured by changes in wind patterns, which are believed to be linked to global warming and the depletion of ozone over the continent, leading to a reduction in temperatures.

Dr. Sarah Jackson, an ice core expert at the Australian National University who was not involved in the study, expressed deep concern about the findings. She pointed out that current projections for future sea-level rise are based on these lower rates of warming, suggesting that ice loss estimates might be underestimated.

Meanwhile, Dr. Danielle Udy, a climate scientist and ice core specialist at the University of Tasmania, also not involved in the study, highlighted the timeliness of the research, particularly in light of recent extreme events in Antarctica.

A puzzling record-low levels of Antarctic sea

Scientists have been puzzled by the record-low levels of Antarctic sea ice in recent years, and some believe that global warming may be influencing the region. In 2022, thousands of emperor penguin chicks likely perished due to the melting of typically stable sea ice that supports colonies in West Antarctica.

Dr. Kyle Clem, a researcher at Victoria University of Wellington in New Zealand, has been studying the recent record-high temperatures at a weather station at the South Pole. Clem noted that while Antarctica's climate naturally experiences significant fluctuations, Casado's study reveals a detectable shift in Antarctic climate and the emergence of human-induced polar amplification.

These findings are significant for understanding the future of Antarctica as greenhouse gas levels continue to rise. A warming Antarctic could lead to further losses of sea ice, impacting ocean warming, global ocean circulation, and marine ecosystems. Additionally, the study suggests that greater warming could result in the melting of coastal ice shelves that protect glaciers, potentially becoming a more widespread occurrence than previously anticipated in a rapidly warming Antarctic climate.