BUBBLE TROUBLE: Siberia is thawing out, leaving the region's frozen tundra to slowly reveal what it's been hiding for the last few millennia. Sometimes it's just woolly mammoth bones, but scientists say a much less benign relic has also begun escaping its permafrost prison: methane, a potent greenhouse gas. Reporting Friday in the journal Science, the researchers say they've discovered undersea permafrost on the East Siberian Arctic Shelf that's releasing plumes of methane, which drifts in bubbles to the ocean surface and floats into the atmosphere. While it's too early to know whether these methane emissions are enough to be dangerous, says co-author Natalia Shakhova, they aren't trivial. "The amount of methane currently coming out of the East Siberian Arctic Shelf is comparable to the amount coming out of the entire world's oceans," she tells the AP, noting that methane can trap heat in the atmosphere 30 times more effectively than carbon dioxide. Once enough permafrost begins emitting its stored methane, scientists warn of a climatic "feedback loop," with rising temperatures releasing more and more methane, which then makes temperatures rise even faster. (Sources: New York Times, Associated Press)

 

COOKED LIZARDS: A 7.5-mile-wide asteroid killed off the dinosaurs 65.5 million years ago, an international team of experts announced Thursday, putting to rest once and for all the debate over how Earth's era of giant lizards came to an end. The news isn't exactly news, since this scenario was first proposed 30 years ago, but the all-star squad of scientists was assembled to answer any remaining doubts about the so-called Cretaceous-Tertiary (KT) extinction, namely whether erupting volcanoes in India are more likely culprits. But the asteroid — which smashed into the Gulf of Mexico with the force of 1 billion atomic bombs — offers a better explanation for the "hellish environment" that followed, the scientists say. The collision blew debris across the planet, flattened forests, sparked huge wildfires and triggered earthquakes greater than magnitude 10, often stirring up towering tsunamis. But before you feel too sorry for the dinosaurs, one of the study's co-authors reminds us that things played out pretty well for mammals: "The KT extinction was a pivotal moment in Earth's history, which ultimately paved the way for humans to become the dominant species on Earth." (Sources: Reuters, Los Angeles Times, BBC News)

 

EMISSIONS POSSIBLE: As it become clear that Congress wouldn't pass a climate bill last year, the Obama administration began to begrudgingly work on its Plan B — the EPA declared that greenhouse gas emissions are a threat to public health, allowing the agency to regulate them under the existing Clean Air Act. But now, as the Washington Post reports, many lawmakers in Congress have begun waging war on Plan B, too, threatening to derail President Obama's attempts to slow the approach of climate change. Members of both chambers and both parties have drafted bills aimed at stopping the EPA from regulating greenhouse gas emissions, but one — introduced by Sen. John D. Rockefeller IV, D-W.Va (pictured) — could potentially win over many moderate Democrats who are facing tough election fights in the fall. Rockefeller's bill would place a two-year freeze on the EPA's ability to regulate power plants' carbon emissions, and some experts say it could delay regulations by at least four years. "Today, we took important action to safeguard jobs, the coal industry and the entire economy," says Rockefeller, who argues the two-year delay will give Congress time to come up with its own climate bill. (Source: Washington Post)

 

WHERE THE BUFFALO ROAM: North America's bison may have been saved from extinction following a wave of overhunting during the 1800s, but that was about it. Now it's time for a "second recovery," according to a new report from the International Union for the Conservation of Nature, which argues that more land must be made available, government policies must be updated and public attitudes must be changed before the comeback of North America's largest land mammal can really be considered a success. "The decimation of the American bison in the late 1800s inspired the first recovery of bison and an entire conservation movement that protected wildlife and wild places across North America," says an author of the report. "The IUCN Status Survey and Conservation Guidelines provide a new framework for inspiring a second recovery of bison and restoring functional grassland ecosystems." Tens of millions of bison milled around from Alaska to northern Mexico 500 years ago, but they were nearly wiped out by hunters and habitat loss. There are now some 400,000 in commercial herds across the continent, but efforts to boost conservation herds have largely stalled — threatening the animals' genetic diversity as well as our appreciation of their ecological roles. "While substantial progress in saving bison from extinction was made in the 20th century, much work remains to restore conservation herds throughout their vast geographical range," a co-editor of the report says. "The key is recognition that the bison is a wildlife species and to be conserved as wildlife, it needs land and supportive government policies." (Source: ScienceDaily)

 

SNOW GLOBE: The winter of 2009-'10 may have been pretty bad in the United States and parts of Europe, but it was nothing compared with winters 716.5 million years ago. Geologists report this week in the journal Science that they've found evidence of sea ice extending all the way to the equator back then, adding strong new evidence to the "snowball Earth" theory, which suggests the entire planet was once covered in ice. The researchers studied ancient tropical rocks that are now in Canada (thanks to tectonic drift), finding evidence of glacial deposits dating from the time when the rocks were located near the equator. "This is the first time that the Sturtian glaciation has been shown to have occurred at tropical latitudes, providing direct evidence that this particular glaciation was a 'snowball Earth' event," says lead author Francis Macdonald of Harvard University, adding that the planet remained snowverwhelmed for at least 5 million years. Not only did multicellular life manage to survive this event, but the researchers even speculate that the big freeze may have helped spark the evolution of animals, pointing out that changing climatic conditions often force life to come up with elaborate ways to adapt. "From an evolutionary perspective," Macdonald says, "it's not always a bad thing for life on Earth to face severe stress." (Source: e! Science News)

 

FLIP CUP: As President Obama continues undoing some of his predecessor's less eco-friendly efforts, Politico reports that the White House has thrown out one of the last wasteful remnants of the Bush administration: its hot beverage cups. The Obama administration has been reviewing the cup issue for about a year, according to the White House Council on Environmental Quality, but decided to use up the last of the Bush-era cups before replacing them. The new shipment arrived this week, and the cups are not only more biodegradable, but 12 percent of each one is made from recycled post-consumer content, as are 99 percent of the cups' interior liners. They'll join the administration's existing cold-beverage cups, which are made from a green, plant-based polylactic acid. (Source: Politico)

 

— Russell McLendon

 

 

Image (artist's rendering of asteroid impact that killed dinosaurs): National Science Foundation