During the winter, sea ice that is essential to the marine food web usually grows around Antarctica. Warming temperatures are slowing that growth. By Kristin Toussaint4 minute Read It’s currently winter in Antarctica, but that doesn’t mean the polar region is exempt from the extreme temperatures that are scorching the world. While normally the ocean around Antarctica freezes in the winter, growing sea ice that is essential to the marine food web, this year that ice isn’t growing as usual. “What we’re seeing this year we’ve never seen before,” says Oscar Schofield, chair of the Marine Science Program at Rutgers University and one of the principal investigators for Palmer LTER, a Long Term Ecological Research site on Antarctica. “Unless something dramatic happens in late winter, which I’m not expecting, this will be the lowest year ever recorded for sea ice.” Sea ice grows throughout the winter, historically reaching its peak in September at about 19 million square kilometers, or 7 million square miles. (North America, for comparison, is about 9.5 million square miles.) But the ice isn’t growing to that level this year. The decline is so extreme that researchers have been calling it a “five-sigma event,” basically referring to how many standard deviations it is beyond the mean: “It’s like, okay, we’re five times outside of deviations,” Schofield says, “so it’s an extreme event.” As of June 27, Antarctic sea ice measured 1.6 million square kilometers (618,000 square miles) below the previous record low for that date set in 2022, according to the National Snow & Ice Data Center—and more than 2.6 million square kilometers (1 million square miles) below the 1981 to 2010 average. Before 2015, some areas around Antarctica would see large declines in sea ice, but other areas were still growing more, so it essentially balanced out. Since 2016 there’s been a “hemispheric decline” in the amount of sea ice year to year. “But this year is particularly stunning in how little sea ice has formed around the continent,” Schofield says. The trend has big implications for the planet. Antarctica is already warming faster than the rest of the world, with the Antarctic Peninsula in particular warming five times faster than the global average. The ocean also takes in a lot of the atmospheric carbon that we produce, and the Southern Ocean, also known as the Antarctic Ocean, is responsible for 30% to 40% of that. ​“If you change the state of the Southern Ocean, there’s great potential for it to have big ramifications on planetary carbon, biogeochemistry, and all those kinds of things,” Schofield says. “There are a lot of discussions going on now about, what does a super-low-sea-ice year like this mean?” There are also questions about what the decline means for the Antarctic life that has evolved around sea ice. In the winter, Antarctic winds increase, which can mix up the ocean water. Sea ice provides a substrate, or “tabletop,” Schofield says, that protects the surface of the ocean. The upper ocean is important for plants that need to catch sunlight, and in years after there’s been a lot of sea ice, researchers tend to see big blooms of plankton in the spring—which then feed krill, ensuring there’s krill to feed whales, penguins, fish, and so on. “One prediction might be that with no sea ice, plankton blooms are smaller, and then we see that ripple up through the food web,” Schofield says. His research team is just starting to gear up for its field work, which begins in October and includes research cruises in January, so he’s not quite sure what the impact of this low-sea-ice winter will be down the line. “Is this going to be one of those years where the system fundamentally flips to be in a new state? We don’t know the answer,” he says. “But we do know that this [extreme] level is going to be sort of a prime experiment in terms of what future Antarctic ecosystems might look like.” Ecosystems could also be affected by warming water, and less sea ice means the ocean absorbs more warmth from the sun. (White ice reflects the sun, but the blue of the ocean absorbs heat from sunlight.) “Once it starts to run away it becomes worse,” says David Holland, a professor of mathematics and climate science at New York University who studies both the Arctic and Antarctic. “When summer comes to polar regions, it’s 24 /7 sunlight . . . and so you just get this really big impact. . . . Not having ice means sunlight is absorbed really efficiently by the blue ocean.” Less sea ice doesn’t change the sea level, though, since sea ice often melts and re-forms—but it can cause the planet to warm faster than current models show, Holland adds. And if that warm ocean starts to melt the continent of Antarctica and its thick, miles-deep ice, that means sea levels could rise. These trends certainly stem from human-induced climate change and higher levels of carbon dioxide in the atmosphere, but natural climate cycles like El Niño can magnify the effects of climate change. Essentially, a lot of things are happening to the planet at once—but the lack of sea ice and the condition of the Antarctic is extreme. “It’s absolutely mind-boggling,” Holland says. “It’s such a massive change.” Original article at Fast Company Photo credit; Sebnem Coskun/Anadolu Agency/Getty Images

Sentinel Home The Sentinel Mission Flight Viewer Our Goals Our Challenges UN Ocean Decade What is a Glider? What Gliders Can Do Slocum Gliders The Sentinel Glider History Doug Webb and Henry Stommel’s Challenge to Humanity Scarlet Knight’s Atlantic Crossing Our Team Topics in Marine Science Teledyne Technologies Get Involved Social Media Mission Donors Outreach Events Sentinel Blog Sentinel Home The Sentinel Mission Flight Viewer Our Goals Our Challenges UN Ocean Decade What is a Glider? What Gliders Can Do Slocum Gliders The Sentinel Glider History Doug Webb and Henry Stommel’s Challenge to Humanity Scarlet Knight’s Atlantic Crossing Our Team Topics in Marine Science Teledyne Technologies Get Involved Social Media Mission Donors Outreach Events Sentinel Blog https://rucool.marine.rutgers.edu/wp-content/uploads/2023/03/glider.mp4 Gliders are an unique tool that has revolutionized how society collects ocean data. By using buoyancy as a means to move through the ocean, batteries can allow gliders to move through the ocean. This allows scientists to maintain the a presence at sea under violent conditions, remote locations and their modular nature allows a wide range of science sensors to meet many science needs.  https://rucool.marine.rutgers.edu/sentinel-glider-2/slocum-gliders/ https://www.teledynemarine.com/brands/webb-research/slocum-glider

Sentinel Home The Sentinel Mission Flight Viewer Our Goals Our Challenges UN Ocean Decade What is a Glider? What Gliders Can Do Slocum Gliders The Sentinel Glider History Doug Webb and Henry Stommel’s Challenge to Humanity The Scarlet Knight’s Atlantic Crossing Our Team Topics in Marine Science Teledyne Technologies Get Involved Social Media Mission Donors Outreach Events Sentinel Home The Sentinel Mission Flight Viewer Our Goals Our Challenges UN Ocean Decade What is a Glider? What Gliders Can Do Slocum Gliders The Sentinel Glider History Doug Webb and Henry Stommel’s Challenge to Humanity The Scarlet Knight’s Atlantic Crossing Our Team Topics in Marine Science Teledyne Technologies Get Involved Social Media Mission Donors Outreach Events What can a glider do? Slocum Gliders The Sentinel Glider

It’s been a spring of alarming headlines for the coldest climates on Earth, from record heat waves at both poles, to a never-before-seen ice shelf collapse in East Antarctica. But what can we say for sure about how the Arctic and Antarctic are changing under global warming? In this Zoom taping, guest host Umair Irfan talks to two scientists, Arctic climate researcher Uma Bhatt and Antarctic biological oceanographer Oscar Schofield, about the changes they’re seeing on the ice and in the water, and the complex but different ecologies of both these regions. Plus, answering listener questions about the warming polar regions. Original article and video at Science Friday

Thanks to carbon emissions, the ocean is changing, and that is putting a whole host of marine organisms at risk. These scientists are on the front lines. Eric Niiler | National Geographic Grace Saba steadies herself on the back of a gently rocking boat as she and her crew slide a six-foot long yellow torpedo into the sea. A cheer erupts as the device surfaces, turns on its electronic signal, and begins a three-week journey along the New Jersey coast. “It’s taken seven years to get this done,” said Saba, who has been working on this experiment since 2011. “I’m so happy, I think I might cry!” Saba is an assistant professor of marine ecology at Rutgers University, where she is studying how fish, clams, and other creatures are reacting to rising levels of ocean acidity. Acidification is a byproduct of climate change; a slow but exorable real-life experiment in which industrial emissions of carbon dioxide into the atmosphere are absorbed and then undergo chemical reactions in the sea. Rising ocean acidity has already bleached Florida’s coral reefs and killed valuable oystersin the Pacific Northwest. Now scientists like Saba want to know what might happen to animals that live in the Northeast, a region home to commercially important fishes, wild stocks of quahogs (clams), scallops, and surf clams that can’t swim away from growing acidic waters. “They are just stuck there,” Saba said. Saba’s torpedo-like instrument is actually an underwater drone, known as a Slocum glider, that is carrying an ocean acidity sensor. This is the first time that oceanographers have married the two technologies—glider and pH sensor—to get a big-picture view of changes underway in the commercially important fishing grounds of the Northeastern United States. The glider will travel 130 miles from Atlantic City to the edge of the underwater continental shelf and back. It will complete a series of dives to the ocean bottom, sampling water temperature, salinity, and pH as it swims. The glider will feed Saba and colleagues data on changing water chemistry more quickly than the testing conducted every four years by seagoing oceanographic vessels. Rising Acid Saba and Rutgers graduate student Liza Wright-Fairbanks are hoping to compare ocean pH measurements to coastal fish spawning grounds. Developing fish and shellfish larvae are most vulnerable to rising ocean acidity. “We don’t know much about pH throughout the entire water column, especially here along the East Coast and the commercial fisheries here,” said Wright-Fairbanks. “They bring in so much money to the country, but if the shellfish can’t survive than neither can the fishermen.” Scientists say the pH level of the world’s seas have already dropped—on average from 8.2 to 8.1 on the pH scale (lower numbers are more acidic). That’s a 26 percent drop in the past century (because the pH scale is logarithmic). But as the ocean absorbs more industrial emissions of carbon dioxide, its pH is expected to double to 7.7 pH units by the end of the century, according to Aleck Wang, professor of marine chemistry at the Woods Hole Oceanographic Institution. The result is that, by 2100, “you are going to start seeing calcium carbonate shells dissolve,” Wang said. “It’s not going to be that far away.” By killing such critical shelled organisms as corals, oysters, and many plankton, acidic waters may upend the ocean food chain. Fishermen in the Gulf of Maine are already seeing seasonal changes in ocean acidity that could one day threaten a seafood harvest worth more than $600 million to Maine’s economy. Further south in the Mid-Atlantic region, seafood harvesters worry about their future as well. “We are all trying to figure out the right path forward,” said A.J. Erskine, owner of a commercial oyster hatchery on the Potomac River in Virginia. “I don’t know if there is a solution, but the more data we have the more knowledge we have. If we don’t know the pH, how can we address it?” Erskine is part of a group of fishermen, scientists, and state fisheries managers called the Mid-Atlantic Coastal Acidification Network that is pushing for more research and attention on the issue. Scientists at the University of Delaware and NOAA just deployed the first permanent buoy to measure carbon dioxide levels in Chesapeake Bay, the largest estuary in the eastern United States. The moored buoy will help researchers figure out whether the bay can handle more CO2 from the atmosphere while also dealing with man-made pollution from surrounding farms and factories. In another attempt to study acidification, researchers at the National Oceanic and Atmospheric Administration launched 23-foot long surface drones powered by sail across the Pacific and Arctic Oceans to gather wind, temperature, and acidity data. They hope to eventually use the mobile saildrones to replace aging surface buoys that are tethered to the seafloor. Grace Saba of Rutgers takes water samples to better understand the changing ocean. And just as some scientists are trying to develop corals that are more resistant to acidic waters, Erskine says that one solution may be to find oysters, clams, and other fish that are resilient as well. “The way we can do that is by manipulating the tanks in the hatchery,” Erskine said. Of course, that only works for farm- or hatchery-raised species. “It’s more difficult when you are talking about Chesapeake Bay or the Gulf of Maine.” Gambling on the Future Back on the boat, Saba, Wright-Fairbanks, and Rutgers research professor Travis Miles spend the morning at sea testing the Slocum glider. They want to make sure its instruments are working perfectly before putting it on auto-pilot and sending it on its environmental mission. Each in turn throws overboard a gray plastic water sampling bottle attached to a rope known as a CTD. Those old-school measurements of water quality are then compared to sensor readings on the glider. After the Rutgers team deploys the glider, the 46-foot crewboat returns to a marina near the Golden Nugget casino in Atlantic City. Wright-Fairbanks is just starting her PhD at Rutgers,

Last week, RUCOOL’s high frequency radar team proudly sent Tim to the University of Southern Mississippi for the 13th Radiowave Operators Working Group (ROWG) meeting. This event was a fantastic opportunity for Tim to meet and collaborate with many operators he had previously only interacted with virtually. The meeting was a significant milestone for the ROWG community, providing a platform to exchange knowledge and experiences with CODAR’s high-frequency radars while also discussing the future of HF radar during a transitionary period of the HF radar Data Access Center. Tim had aninvaluable opportunity to deepen his expertise, and discuss the latest advancements and applications in ocean observing technology amongst other HF radar operators. The Rutgers HF Radar team is eager to use what was learned at the meeting, and looks forward to implementing new ideas to enhance their research and operational capabilities!

Michael just completed an awesome Master’s thesis with a focus on the “Spatial and Seasonal Controls on Eddy Subduction in the Southern Ocean”.  With profiling ocean robots, mixing, phytoplankton and Southern Ocean, what is there not to love?  Great job Michael!!!