An Iceberg the Size of Delaware Is About to Break Away From Antarctica

John Sonntag, NASA // Public Domain
John Sonntag, NASA // Public Domain

The crack in the Antarctic ice has been growing for years. Now scientists say a major break is coming—an event that could set in motion the disintegration of the entire 19,000-square-mile Larsen C ice shelf.

The entire Larsen ice shelf, comprising Larsen A, B, C, D, E, F, and G, wraps like a crumbling white blanket around the Antarctic Peninsula. The rift in Larsen C started small, as these things do, but with each passing day its expansion accelerates. By June 24, the crack was widening by about 32 feet per day.

Aerial shot of a rift in the Larsen C ice shelf.
John Sonntag, NASA // Public Domain

Scientists at the UK-based Project MIDAS say a big break is imminent. "We still can't tell when calving will occur," they wrote on their website, "it could be hours, days or weeks—but this is a notable departure from previous observations."

The loss of the Delaware-sized iceberg—one of the largest ever recorded—will be both dramatic and destabilizing for its parent ice shelf.

"When it calves," the researchers write, "the Larsen C Ice Shelf will lose more than 10 percent of its area to leave the ice front at its most retreated position ever recorded. This event will fundamentally change the landscape of the Antarctic Peninsula."

It could also trigger Larsen C's total collapse into the sea, which could, in turn, raise worldwide sea levels by four inches.

The break will be the third major calving from the Larsen ice shelf in recent memory. The area called Larsen A collapsed in 1995, followed by Larsen B in 2002. The latter was double the size of greater London.

The researchers have no evidence directly linking this particular break to climate change, but as a press statement noted, "It is widely accepted that warming ocean and atmospheric temperatures have been a factor in earlier disintegrations of ice shelves elsewhere on the Antarctic Peninsula."

Being Surrounded By Greenery Can Be Good for Your Heart

iStock.com/Givaga
iStock.com/Givaga

Living in a place with a little greenery is good for your health in more ways than one. Recent research has found that people perceive their health status as significantly better if they live around trees, and for good reason—in addition to helping you chill out, exposure to lots of green vegetation may be good for your cardiovascular health, as Cardiovascular Business reports.

A new study in the Journal of the American Heart Association suggests that living in green areas is correlated with certain biomarkers for cardiovascular health. Scientists analyzed blood and urine samples from 408 people at a cardiology clinic, then compared the results to satellite-derived data on the levels of greenery around those patients’ homes (using 820-foot and half-mile radiuses).

Adjusting for age, sex, race, smoking status, “neighborhood deprivation” and other factors known to be linked heart disease rates, the researchers found that living in a green area was correlated with several markers of a healthy heart. Blood and urine samples from those participants who lived in green neighborhoods showed lower levels of sympathetic activation—the body’s automatic fight-or-flight response, which raises the heart rate and is involved in heart failure. Those participants also had reduced oxidative stress—an imbalance between free radicals and antioxidants in the body, which can cause tissue damage and is linked to chronic disease. And they had higher angiogenic capacity, which refers to the body’s ability to form new blood vessels.

All this suggests that being around trees is somehow linked to having a healthier heart, though these are just biomarkers, not rates of heart disease or major cardiac events. But while scientists have yet to prove directly that being around trees causes your heart to be healthier, it’s not the first study to suggest a link. In 2015, a study of American women found that rates of heart disease went up in certain areas after a beetle invasion killed off a significant number of trees. Other studies have suggested that being around trees can reduce stress, which in itself may affect your risk of heart disease. Luckily, whether it qualifies as heart medicine or not, spending more time hanging out under trees couldn’t hurt.

[h/t Cardiovascular Business]

Survey Finds Microplastics in the Guts of All Seven Sea Turtle Species

iStock.com/RainervonBrandis
iStock.com/RainervonBrandis

Plastic is all around us—in our landfills, in our oceans, and even in the bellies of some of Earth's most vulnerable creatures. For a new paper in the journal Global Change Biology, researchers checked the guts of 102 deceased sea turtles, some of which belong to critically endangered species, and found that all of them tested positive for microplastics.

For the study, UK-based researchers from the University of Exeter, Plymouth Marine Laboratory, and Greenpeace Research Laboratories studied turtles that had died after being stranded or accidentally caught by commercial fishing operations. All seven marine turtle species were tested, including the endangered green turtle and the critically endangered hawksbill and Kemp's ridley turtles.

The specimens were found off the coasts of North Carolina in the Atlantic Ocean, northern Cyprus in the Mediterranean Sea, and Queensland, Australia in the Pacific Ocean. Necropsies revealed plastic particles under 5mm in length, while microplastic fibers were one of the most common contaminants detected in their guts. These can come from a variety of sources, including clothing, tires, cigarette filters, ropes, and fishing nets. More than 800 synthetic particles were found in the turtles. Only one section of the gut was tested in each animal, so the actual number is likely 20 times higher, according to a University of Exeter statement.

A 2015 study, also in Global Change Biology, estimated that 52 percent of all sea turtles may have ingested microplastics.

"From our work over the years, we have found microplastic in nearly all the species of marine animals we have looked at, from tiny zooplankton at the base of the marine food web to fish larvae, dolphins, and now turtles," Dr. Penelope Lindeque, of the Plymouth Marine Laboratory, said in the statement. "This study provides more evidence that we all need to help reduce the amount of plastic waste released to our seas and maintain clean, healthy, and productive oceans for future generations."

The consequences of ingesting microplastics—via contaminated water or by eating other fish or plants—isn't currently known. The particles are small enough to pass through the gut without causing any blockages, unlike larger plastics which can—and do—wreak havoc on marine life. While the authors concluded that microplastics, at their current levels, post less of a threat than fisheries bycatch and entanglements in fishing gear, they said further studies should be conducted to determine the actual risks.

"They may possibly carry contaminants, bacteria, or viruses, or they may affect the turtle at a cellular or subcellular level," lead author Dr. Emily Duncan of the University of Exeter said. "This requires further investigation."

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