scitechdaily

  Brain Shrinkage: Even Mild Cases of COVID-19 Can Leave a Mark on the Brain, Such As Reductions in Gray Matter Researchers have been steadily gathering important insights into the effects of COVID-19 on the body and brain. Two years into the pandemic, these findings are raising concerns about the long-term impacts the coronavirus might have on biological processes such as aging. As a cognitive neuroscientist, I have focused in my past research on understanding how normal brain changes related to aging affect people’s ability to think and move – particularly in middle age and beyond. But as evidence came in showing that COVID-19 could affect the body and brain for months following infection, my research team shifted some of its focus to better understanding how the illness might influence the natural process of aging. This was motivated in large part by compelling new work from the United Kingdom investigating the impact of COVID-19 on the human brain. Peering in at the brain’s respons

  NASA’s ICESat-2 Mission Maps 16 Years of Melting Greenland and Antarctic Ice Sheets This shows the amount of ice gained or lost by Antarctica between 2003 and 2019. Dark reds and purples show large average rates of ice loss near the coasts, while blues show smaller rates of ice gain in the interior. The ice lost near the coasts, especially West Antarctica and the Antarctic Peninsula, vastly outweigh gains in the interior. Thwaites and Crosson ice shelves (seen just below the peninsula) have thinned the most. The two ice shelves have lost five meters (16 feet) and three meters (10 feet) of ice per year, respectively, between 2003 and 2019. The circle in the middle is over the South Pole where the instrument does not collect data. Credit: Smith et al./Science Using the most advanced Earth-observing laser instrument NASA has ever flown in space, a team of scientists led by the University of Washington has made precise measurements of how the Greenland and Antarctic ice sheets have chang

  A Recent Reversal Discovered in the Response of Greenland’s Ice Caps to Climate Change Greenland may be best known for its enormous continental scale ice sheet that soars up to 3,000 meters above sea level, whose rapid melting is a leading contributor to global sea level rise. But surrounding this massive ice sheet, which covers 79% of the world’s largest island, is Greenland’s rugged coastline dotted with ice capped mountainous peaks. These peripheral glaciers and ice caps are now also undergoing severe melting due to anthropogenic (human-caused) warming.  However, climate warming and the loss of these ice caps may not have always gone hand-in-hand. New collaborative research from the Woods Hole Oceanographic Institution and five partner institutions (University of Arizona, University of Washington, Pennsylvania State University, Desert Research Institute and University of Bergen), published on September 9, 2021, in Nature Geoscience, reveals that during past periods glaciers and ic

  Explosive Past of Arizona’s Sunset Crater Eruption May Inform Threats of Similar Volcanoes Today Around A.D. 1085, along the southern rim of Northern Arizona’s elevated Colorado Plateau, a volcano erupted, forever changing ancient Puebloan fortunes and all nearby life. Among the 600 or so volcanoes that dot the landscape of the San Francisco volcanic fields, this one blew. It was the very first (and last) eruption for what came to be known as Sunset Crater, aptly named for its multihued, 1,000-foot-tall cinder cone. Today, Arizona State University School of Earth and Space Exploration scientist Amanda Clarke and her team have been working to solve the mysterious root cause of the Sunset Crater eruption and any lessons learned to better understand the threats similar volcanoes may pose around the world today. “This is a common thing in volcanology, to reconstruct past eruptions to try to understand what the volcano or region might do in the future,” Clarke said. “We did the field work

  New Feedback Loops: Climate Change Will Transform Cooling Effects of Volcanic Eruptions Researchers have shown that human-caused climate change will have important consequences for how volcanic gases interact with the atmosphere. The researchers, from the University of Cambridge and the UK Met Office, say that large-magnitude eruptions will have greater effects as the climate continues to warm. However, the cooling effects of small- and medium-sized eruptions could shrink by as much as 75%. Since these smaller eruptions are far more frequent, further research is needed to determine whether the net effect will be additional warming or cooling. Where and when a volcano erupts is not something that we can control, but as the atmosphere warms due to climate change, the plumes of ash and gas emitted by large, but infrequent, volcanic eruptions will rise ever higher. Climate change will also accelerate the transport of volcanic material – in the form of small, shiny droplets called volcani

  The Anatomy of Glacial Ice Loss: Glaciers Are Far More Complex Than Ice Cubes A warming climate is taking its toll on Greenland and Antarctica glaciers, melting them from above and below the surface. The more they melt, the higher sea levels rise. When an ice cube is exposed to a heat source, like warm water or air, it melts. So, it’s no surprise that a warming climate is causing our glaciers and ice sheets to melt. However, predicting just how much the glaciers and ice sheets will melt and how quickly – key components of sea level rise – is not nearly as straightforward. Glaciers and ice sheets are far more complex structures than ice cubes. They form when snow accumulates and is compressed into ice by new snow over many years. As they grow, they begin to move slowly under the pressure of their own weight, dragging smaller rocks and debris across the land with them. Glacial ice that extends to cover large landmasses, as it does in Antarctica and Greenland, is considered an ice sheet

  Intact Plant Fossils Discovered Beneath Greenland’s Ice Sheet After Lucky Find of Ice Cores Drilled by U.S. Military in 1966 For the first time ever, researchers have found fossils under Greenland’s ice sheet that are so large and well preserved that they can be seen with the naked eye. The fossils reveal several million years of details about climate and plant life in Greenland according to the UCPH researcher behind the discovery. Following a relocation of ice cores to the Copenhagen suburb of Rødovre in 2017, University of Copenhagen researchers found unopened boxes of ice cores dating back to 1966—the first ice cores drilled on Earth. Analyses of the long-forgotten ice have now been completed and are presented in a new study with groundbreaking results. Within the cores, which come from deep within the ice sheet at Camp Century, Greenland, the UCPH researchers and their Belgian and American colleagues became the first ever to find these millions of years old macrofossils. The fos

  Yet Another Wake-Up Call” – Greenland on Track to Lose Ice Faster Than in Any Century Over the Last 12,000 Years The research places the ice sheet’s modern decline in historical context, providing a robust look at how this century’s losses could starkly outpace prior changes. If human societies don’t sharply curb emissions of greenhouse gases, Greenland’s rate of ice loss this century is likely to greatly outpace that of any century over the past 12,000 years, a new study concludes. The research will be published on Sept. 30 in the journal Nature. The study employs ice sheet modeling to understand the past, present and future of the Greenland Ice Sheet. Scientists used new, detailed reconstructions of ancient climate to drive the model, and validated the model against real-world measurements of the ice sheet’s contemporary and ancient size. The findings place the ice sheet’s modern decline in historical context, highlighting just how extreme and unusual projected losses for the 21st

  Scientists Stunned to Discover Plants Beneath Mile-Deep Greenland Ice – Why This Spells Trouble Most of Greenland is covered with ice today. But a new study shows that within the last million years it melted off and became covered with green tundra, perhaps like this view of eastern Greenland, on the coast near the ocean. The research provides strong evidence that Greenland is more sensitive to climate change than previously understood–and at risk of irreversibly melting. Credit: Joshua Brown/UVM Long-lost ice core provides direct evidence that giant ice sheet melted off within the last million years and is highly vulnerable to a warming climate. In 1966, US Army scientists drilled down through nearly a mile of ice in northwestern Greenland — and pulled up a fifteen-foot-long tube of dirt from the bottom. Then this frozen sediment was lost in a freezer for decades. It was accidentally rediscovered in 2017. The discovery helps confirm a new and troubling understanding that the Greenla

  Ancient Ice Reveals Scores of Gigantic Volcanic Eruptions – Causing Tsunamis, Drought, Famine, and Death Ice cores drilled in Antarctica and Greenland have revealed gigantic volcanic eruptions during the last ice age. Sixty-nine of these were larger than any eruption in modern history. According to the University of Copenhagen physicists behind the research, these eruptions can teach us about our planet’s sensitivity to climate change. For many people, the mention of a volcanic eruption conjures up doomsday scenarios that include deafening explosions, dark ash billowing into the stratosphere, and gloopy lava burying everything in its path as panicked humans run for their lives. While such an eruption could theoretically happen tomorrow, we have had to make do with disaster films and books when it comes to truly massive volcanic eruptions in the modern era. “We haven’t experienced any of history’s largest volcanic eruptions. We can see that now. Eyjafjellajökull, which paralyzed Europ