New study offers climate clues from most recent interglacial warm period
By Bob Berwyn
The last time the Earth was as warm as today was about 128,000 years ago — and Antarctic sea ice extent was 65 percent smaller than it is now, according to British scientists who tracked past climate change in the region by studying ice core samples from that era.
That means Antarctic sea ice is on course to shrink dramatically in the decades and centuries ahead, said British Antarctic Survey scientist Max Holloway, who with a team of researchers analyzed oxygen isotopes in ice and air bubbles trapped for 128,000 years in the East Antarctic Ice Sheet. Continue reading “Antarctic sea ice meltdown likely in a warming world”→
Larsen C Ice Shelf has dwindled by 4 meters in 15 years
FRISCO — One of Antarctica’s giant ice shelves has thinned by more than 12 feet in the past 15 years and could collapse within the next 100 years — or possibly sooner and without much warning, according to scientists with the British Antarctic Survey.
FRISCO — After studying fur seals around Antarctica for decades, researchers with the British Antarctic Survey say they’re seeing distinct genetic changes related to a changing climate and food availability. But despite a shift towards individuals more suited to changing environmental conditions, this fitness is not passing down through generations, leaving the fur seal population on South Georgia Island in decline. Continue reading “Climate change drives Antarctic fur seal decline”→
Recent satellite observations show birds adapting to changes in sea ice
By Bob Berwyn
FRISCO — Emperor penguins living at the edge of their range may be able to find new breeding grounds as their sea-ice breeding habitat dwindles in coming decades.
Recent satellite monitoring shows that the Antarctic birds moved from their traditional sea-ice breeding grounds during years when the thin layer of ice (sea ice) formed later than usual to the much thicker floating ice shelves that surround the continent.
Underwater mountains help churn up the ocean, fueling the carbon cycle
By Summit Voice
FRISCO — The Drake Passage, between the tip of South America and the Antarctic Peninsula, is well known for wild storms and big swell, but it turns out that turbulence isn’t just at the surface.
Far beneath the breaking whitecaps, the area is a crucial ocean mixing ground, where surface water is exchanged with deep water as currents rush over undersea mountains. Those mixing of water layers are crucial to regulating the Earth’s climate and ocean currents, according to researchers who recently traced how that mixing happens. Continue reading “Oceans: Drake Passage seen as mixing ground”→
Core samples from subglacial lake sediments show surprising biological diversity
By Summit Voice
FRISCO — Burrowing 10 feet down into the primal muck at the edge of a receding ice sheet in Antarctica, scientists with the British Antarctic Survey found what they had long been looking for — traces of microbial life dating back nearly a hundred thousand years, including strands of DNA associated with previously unknown bacteria.
For decades, researchers speculated that so-called extremophiles might exist in the cold and dark lakes hidden deep beneath the Antarctic ice sheet. Organisms living in subglacial lakes could hold clues for how life might survive on other planets.