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Scientists Risk Losing Crucial Tools for Studying Melting Antarctic Ice Sheets Amid Rising Climate Threats

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The decommissioning of Palmer has played a significant role in contributing to sea level rise, particularly as certain regions of Antarctica face limited access, raising concerns among scientists regarding potential ice sheet collapses.

In a statement to NBC News, the National Science Foundation (NSF) announced plans to streamline resources by consolidating McMurdo, Amunsense Cott South Paul, and Palmer Station, with the goal of maintaining three research stations operating throughout the year in Antarctica.

A spokesperson for the U.S. Antarctic Program (USAP) mentioned that they aim to “maintain an active and influential presence in Antarctica while facilitating cutting-edge research in biology and glaciology.”

The NSF was the first to propose the termination of the lease this spring, following the Trump administration’s proposed budget cuts of 55%. Scientists expressed their disappointment that Congress initiated the process of abolishing the ship before finalizing its budget.

“Oceanologist Karos Moffat, an associate professor at the University of Delaware, discussed the budgets that have made advancements in both Senate and House appropriations committees.

The NSF is exploring alternative vessels to take on some of Palmer’s responsibilities and plans to return the vessel to its owner, Edison Chowest, a marine transport company based in Louisiana.

In 2024, the NSF finalized the charter of another Antarctic vessel, RV Laurence M. Gould, which has been upgraded to operate in sea ice, rather than utilizing icebreakers. This reduces the options available for enhancing research in polar oceanography and supporting Palmer Station, an annual base on the Antarctic Peninsula that previously depended on two ships.

The NSF mentioned on Friday that there are “alternatives” available to support and resupply Palmer Station, including commercial options.

Measuring 308 feet, the Palmer, named after a 19th-century seal captain, commenced its service in 1992, exploring various regions of Antarctica. The vessel accommodates approximately 22 crew members and can host around 45 scientists.

No other U.S. research vessels can fulfill all the missions that this polar icebreaker is designed for. The vessel is crucial for studying Antarctic ecology, the Southern Ocean carbon cycle, and monitoring the rate at which ice shelves recede and melt, ultimately influencing sea level rise.

Julia S. Werner of the University of Houston, second from the right, friend of Nathaniel B. Palmer.Courtesy Julia S. Werner

While satellites offer valuable data on the dynamics of ice sheet growth and reduction, the primary research on these changes relies on subsurface measurements.

Without such data, U.S. scientists will lack critical insights into the major ice sheets of the Southern Ocean, which are key to predicting future flooding risks in U.S. coastal cities. For instance, researchers highlight that other U.S. vessels are not suitable for safely accessing the notorious Swaitonga glacier, often referred to as the “end of the Apocalyptic Glacier.”

Researchers frequently describe the West Ku as a cork for a bottle that could rapidly drain the West Antarctic ice sheet, serving as a protective barrier against its collapse into the Amundsen Sea. This could result in a sea level rise exceeding 10 feet over a span of hundreds of thousands of years.

By the year 2100, the likelihood of such a collapse could elevate sea levels significantly beyond the 1-3 feet previously anticipated, as indicated in recent reports by the Intergovernmental Panel.

This disintegration could also alter ocean circulation patterns, affecting how quickly the ocean absorbs carbon, which remains an active area of research. Several studies suggest that current Earth temperatures may have surpassed the threshold for collapse, although further investigation is necessary.

Current shifts in mass and stability are influenced by factors occurring hundreds or thousands of feet beneath the water’s surface, necessitating optimal access through robotic instruments.

“To grasp the drastic changes occurring, it’s essential to be at the edge of the ice where it interacts with the ocean,” Werner explained. “And that’s precisely what this boat allows us to do.”

Scientists typically travel to Palmer every two years, using the data collected over the course of a month or more to advance their laboratory research.

The information gathered aboard the vessel is invaluable, enabling scientists to study ice comprehensively for over a decade, adding vital icebreakers to the U.S. science fleet and alleviating the longstanding backlog of researchers seeking fieldwork opportunities at Palmer.

Source: www.nbcnews.com

Researchers find that melting ice sheets are causing a reduction in the speed of the world’s strongest ocean currents

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Antarctic Circulating Current (ACC), which is more than four times as strong as the Gulf Stream, is the world’s strongest ocean current and plays an unbalanced role in the climate system due to its role as a major basin conduit. Scientists at the University of Melbourne and the Research Centre in Nordic Norway have shown that ACC will slow by about 20% by 2050 in high carbon emission scenarios. This influx of freshwater into the southern ocean is expected to alter the properties such as the density (salinity) of the ocean and its circulation patterns.

Sohail et al. High-resolution ocean and sea ice simulations of ocean currents, heat transport, and other factors were analyzed to diagnose the effects of temperature changes, saltiness, and wind conditions. Image credit: Sohail et al. , doi: 10.1088/1748-9326/adb31c.

“The oceans are extremely complex, finely balanced,” says Dr. Bishakhdatta Gayen, liquid mechanic at the University of Melbourne.

“If this current ‘engine’ collapses, serious consequences, including more climate change, including extreme extreme climate variability in certain regions, will accelerate global warming due to a decline in the ability of the ocean to function as a carbon sink. “

The ACC acts as a barrier to invasive species, like the southern burkelp and marine vectors such as shrimp and mollusks, which travel in the current from other continents reaching Antarctica.

If this current slows and weakens, it is more likely that such species will head towards the fragile Antarctica, potentially serious effects on food webs, which could change the available diet of Antarctic penguins, for example.

The ACC is an important part of the marine conveyor belt around the world, moving water around the world and linking the Atlantic, Pacific and Indian seas. These are the main mechanisms of exchange of heat, carbon dioxide, chemicals and biology throughout these basins.

In their study, the authors used Gadi, the fastest supercomputer in Australia located on the Access National Research Infrastructure.

They discovered that transport of seawater from the surface to the deepest could also be slower in the future.

“If ice melting accelerates as predicted by other studies, slowdowns are predicted to be similar in low emission scenarios,” Dr. Sohail said.

“The 2015 Paris Agreement aims to limit global warming to 1.5 degrees Celsius above pre-industrial levels.”

“Many scientists agree that we have already reached this 1.5 degree target, which could have an impact on the melting of Antarctic ice, making it even hotter.”

“Cooperative efforts to limit global warming (by reducing carbon emissions) will limit the melting of Antarctic ice and avoid the expected slowdown in ACC.”

This study reveals that the effects of ice melting and ocean warming on ACC are more complicated than previously thought.

“The melted ice sheets throw a large amount of fresh water from salt water into the salty sea.”

“This sudden change in ocean salinity has a series of results, including weakening of subsidence to the depths of surface seawater (called Antarctic bottom water), and based on this study, it includes weakening of the powerful marine jets surrounding Antarctica,” Dr. Gayen said.

study Published in the journal Environmental Survey Letter.

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Taimoor Sohail et al. 2025. Decreasing the polar current in the Antarctic due to polarization. environment. res. Rent 20, 034046; doi:10.1088/1748-9326/adb31c

Source: www.sci.news

Antarctic ice sheets may be more stable than previously thought

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Ronnes Ice Shelf in the Southwest Pole survived a long time ago

Modis/Zuma Wire/Shutterstock

The main ice shelves in Antarctica seem to have survived the hot period more than 120, 00 years ago. This indicates that the Westwest Pole ice sheet is not as vulnerable as it is thought to complete the complete collapse caused by climate change. You can raise the sea surface by one meter. However, great uncertainty remains.

“It's good news and bad news.” Eric Wolf At Cambridge University in the UK. “There was no worst scenario, but I can't say that it won't happen in the next century or the second century.”

The climate change caused by humans uncertains the future of the Ice bed in the Southwest Pole. If you continue to release high -level greenhouse gases, some models will completely disappear the ice sheet over the next few centuries. The most extreme scenarios projected by the inter -government panel on climate change in 2023 can lead to up to 2 meters up to the sea level by 2100.

Wolf and his colleagues looked at Ronne's ice shelves, a large part of the ice sheet that extends to the sea, to see how they behaved from 117, 00 to 126 to 00 years. Meanwhile, it was part of the last inter -glacier, and the change in the orbital of the earth increased the temperature of the Antarctica even higher than today.

In order to judge the range of Ronne's ice shelves during the warm period, researchers measured the concentration of the sea salt of the ice core about 650 km away from the end of the shelf. When the ice shelf melted between the last glacier, the edge was approaching the core. As a result, the researchers expected that the core was much closer to the ocean, so the core salt concentration would rise 8 times. “It would have been a seaside resort,” Wolf says.

Instead, they discover that the salt concentration between the last glacier is similar to today's concentration or even lower, indicating that the edge of the ice sheet remains far. Other measurements of the coat of water in the core, which maintain evidence of weather patterns affected by the change in the ice sheet, suggest that Ronne's ice shelves lasted during the last ice age.

Wolfff suggests that ice stability in the previous warm period is unlikely that climate change will be completely collapsed as the climate change increases the global temperature. However, he and other researchers say that the rise of the sea surface due to melting of ice is still a big risk.

“That means that there was no complete removal cation in the South Pole, but we do not provide enough information to relax.” Timothy Naish At Werrington Victoria University in New Zealand.

One is that the survival of Ronnes Ice Shelf does not mean that other ice areas such as Swaites and Pine Island have not melt. In fact, Wolf says the record of the core's water level suggests what they did. The ice score used by the researcher did not cover the warmth of the last ice age.

The dynamics of glacial warming between glaciers, which change in the region, are different from today's global warming, where the temperature is rising throughout the planet. For example, Wolf says that warm seawater that reaches Antarctica can accelerate melting by invading under ice.

“This is a really important observation, but I think it will take more time to understand what it means.” Andrea Duton At Wisconsin University Madison School. She emphasizes that researchers are spending 50 years and trying to think about what happened in the Westwest Pole in the last ice age.

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Source: www.newscientist.com