9621 Agnes Crossing, Lake Suzanneview, New Mexico Island 84604-9295.
Antarctic ice often holds secrets waiting to be discovered, and sometimes an unexpected event can reveal these secrets. That’s exactly how the autonomous Seaglider, charmingly named Marlin and
Antarctic ice often holds secrets waiting to be discovered, and sometimes an unexpected event can reveal these secrets. That’s exactly how the autonomous Seaglider, charmingly named Marlin and launched by the University of East Anglia’s School of Environmental Sciences, got accidentally trapped beneath the vast expanse of the Ross Ice Shelf.
In December 2022, Marlin was launched over the Ross Sea and is scheduled to head north into open waters, collecting important data for climate research.
Opposing the plan, Marlin went on an impromptu expedition beneath the Ross Ice Shelf after being swept there by a current coming from the south. The little explorer remained under the ice for four days; During this time, he made 79 deep dives into the space beneath the ice shelf and collected water measurements up to 200 meters below the surface.
During the unwelcome stay, sensors on the Marlin detected a layer of relatively warmer water about 50 meters thick entering the shelf space from the open sea. The temperature of this water inlet ranged from -1.9°C below the ice to a slightly higher -1.7°C. Its heat was likely capable of melting the base of the ice shelf, unlike the freezing-point waters it replaced.
Unexpected findings from the legend of marlin trapped under the ice prompted researchers to review all available measurements over the past four decades. Conclusion? Heat transferred into space has undoubtedly increased over the last 45 years, largely due to the effects of climate change warming the Ross Sea.
“While a temperature increase of one four-thousandth of a degree per year may not seem like much, it could result in additional ice loss of around 20 to 80 cm per year over the 45 years we studied,” said Dr Peter Sheehan. . , lead author of the study.
“We found that the intruding waters were warm enough to melt the lower part of the ice shelf, unlike the freezing-temperature waters they likely displaced.” “What’s new here is that we can virtually track warm water from the open water of the Ross Sea at the ice front into the void. We’ve never seen any of these invasions directly before.”
The study also suggested that certain wind patterns could mobilize warm surface water beneath the Ross Ice Shelf, causing a southward flow across the ocean surface and flowing directly into the ice shelf gap. These wind currents at the ocean surface, known as Ekman currents, carry heat away, effectively increasing the rate at which the ice covering the surface melts.
“As climate change causes the oceans to continue to warm, it seems reasonable to expect that the magnitude of the Ekman heat flux and the melting it causes will increase further. This trend itself is worrying,” says study co-author Professor Karen Heywood.
“The impact of surface water seeps, together with the trends and variability of Ekman dynamics that may cause them, should be included in climate models, especially given the ongoing uncertainty in the response of Antarctic land ice to climate change.”
This is particularly important because oceans absorb and redistribute a significant portion of Earth’s heat. This means that changes in this system can have a significant impact on global weather, sea level and temperature trends.
This is the first time in decades that such a comprehensive data set has been used to study this process. Preliminary information on surface water intrusions has been obtained using open water hydrography studies, observations of marked seals, and data from ships and ice moorings located within the gap.
As we prepare for the future, Marlin’s chance encounter with the Ross Ice Shelf underscores the importance of integrating the effects of surface water interventions and Ekman dynamics into climate models. It also serves as a reminder of our ongoing quest to understand the changing dynamics of our precious blue planet. The study was published in the journal Science Developments.
Source: Port Altele
As an experienced journalist and author, Mary has been reporting on the latest news and trends for over 5 years. With a passion for uncovering the stories behind the headlines, Mary has earned a reputation as a trusted voice in the world of journalism. Her writing style is insightful, engaging and thought-provoking, as she takes a deep dive into the most pressing issues of our time.
