Tag: Antarctic Peninsula

How will Antarctica respond to global warming?

Long-term studies show potential impacts of climate change

Antarctic biodiversity is at risk from climate change. Photo by Bob Berwyn.
Antarctic ecosystems are at risk from climate change. @bberwyn photo.

Staff Report

A new set of scientific reports highlights the value of long-term observations in relatively undisturbed ecosystems and also offers a preview of how global warming may change Antarctica in coming decades.

The research shows that a period of unusual warmth in 2001 and 2002, caused by a confluence two natural climate cycles,  accelerated the microbial food chain and shook up the distribution of penguin populations and thinned glaciers according to October issue of the journal BioScience .

The research came out of two long-term ecological research stations, including Palmer Station, on the West Antarctic Peninsula, where scientists study how “changing sea ice extent influences marine ecology and the multilayered food webs of the coastal, nearshore, and continental slope ecosystems.” Other studies were done at the  McMurdo Dry Valleys LTER, in an ice-free polar desert where glacial meltwater plays a huge role in ecosystems. Continue reading “How will Antarctica respond to global warming?”

Warming oceans seen as main cause of glacier meltdown on the Antarctic Peninsula

Disintegration of ice shelves in East Antarctica could result in a spiraling increase in sea levels. PHOTO BY BOB BERWYN.
Warming ocean water is creeping up the continental shelf around the Antarctic Peninsula and melting glaciers in some parts of the region. @bberwyn photo.

Staff Report

British researchers say regional patterns of melting of glaciers on the Antarctic Peninsula are linked with warming oceans in the region. The Antarctic Peninsula is one of the biggest contributors to sea level rise, so the new finding will help pinpoint how fast and how high seas will rise in the decades ahead.

The southernmost glaciers flowing to the coast on the western side of the Peninsula are retreating rapidly, but those in the north show little change, the scientists said in a new study published last week in the journal Science. Since accurate measurements started in the 1940s, 94 percent of the 674 glaciers in the region have retreated. Continue reading “Warming oceans seen as main cause of glacier meltdown on the Antarctic Peninsula”

Climate: Study tracks loss of biodiversity near melting Antarctic glaciers

How will global warming affect marine ecosystems around the Antarctic Peninsula? @bberwyn photo.

Increasing sediment load affects bottom-dwelling sea creatures

Staff Report

A series of research dives around the Antarctic Peninsula suggest that melting glaciers are diminishing the region’s biodiversity. Scientists think the main cause may be increased levels of sediment in the water.

Over the past five decades, temperatures have risen nearly five times as rapidly on the western Antarctic Peninsula than the global average. Yet the impacts of the resulting retreat of glaciers on bottom-dwelling organisms remain unclear. Continue reading “Climate: Study tracks loss of biodiversity near melting Antarctic glaciers”

Climate: Icebergs scouring biodiversity from sea-bottom boulders around the Antarctic Peninsula

‘The Antarctic Peninsula can be considered an early warning system … ‘

Icebergs near the shore of the Antarctic Peninsula are scouring the sea-bottom of its biodiversity, according to researchers with the British Antarctic Survey. bberwyn photo.

Staff Report

FRISCO — Antarctic icebergs set free to roam near the shore by global warming are fundamentally changing the seafloor ecology, according to researchers with the British Antarctic Survey.

Boulders on the shallow seabed — once encrusted with a rich assemblage of species in intense competition for limited space — now mostly support a single species. The climate-linked increase in iceberg activity has left all other species so rare as to be almost irrelevant, according to the new study published in the Cell Press journal Current Biology on June 16.

“The Antarctic Peninsula can be considered an early warning system—like a canary in a coal mine,” says David Barnes of the British Antarctic Survey. “Physical changes there are amongst the most extreme and the biology considered quite sensitive, so it was always likely to be a good place to observe impacts of climate change—but impacts elsewhere are likely to be not too far behind. A lot of the planet depends on the near-shore environment, not least for food; what happens there to make it less stable is important.” Continue reading “Climate: Icebergs scouring biodiversity from sea-bottom boulders around the Antarctic Peninsula”

‘Heatwave’ at South Pole sets records

More record-warm Antarctica temperatures recorded in September

Global weirding? Antarctic sea ice hits record highs and South Pole sees record high temps. bberwyn photo.
Global weirding? Antarctic sea ice hits record highs and South Pole sees record high temps. bberwyn photo.

By Summit Voice

FRISCO — While scientists recently pinpointed areas with all-time record low temperatures in Antarctica, the South Pole is not immune to global warming — scientists based at the bottom of the world say the past winter was the warmest since record-keeping started in 1957.

In August, for example, the average temperature for the month was more than 11 degrees Fahrenheit above average, at minus 63.9 degrees Fahrenheit.

The trend continued into the Austral spring, with September 2013 also ending up as an all-time record warm month, including four daily maximum temperature records, according to the Antarctic Sun.

That’s not to say the weather was balmy — the average annual temperature at the South Pole is about minus 56.9 degrees Fahrenheit. The coldest reading on record was minus 117 degrees Fahrenheit, set June 23, 1982, while the warmest temperature recorded since 1957 was just a few years ago, Christmas Day, 2011, when the official high was 9.9 degrees Fahrenheit. Continue reading “‘Heatwave’ at South Pole sets records”

Oceans: Drake Passage seen as mixing ground

Strong storms help push water through the Drake Passage, and beneath the surface, the surging currents help mix the ocean from top to bottom. bberwyn photo.

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”

Global warming: Moss bank core samples from Antarctic Peninsula offer new climate clues

‘Unprecendented rate of ecological change’

A careful study of moss banks on the Antarctic Peninsula has given researchers a new way to measure global warming impacts. bberwyn photo.

By Summit Voice

FRISCO — Finding ways to assess the impacts of global warming in Antarctica isn’t always easy. Measurements of ice help show some of the changes but don’t tell the whole story, so British researchers took a close look at a 150-year-old moss bank on the Antarctic Peninsula, one of the fastest-warming regions on Earth.

The analysis shows an unprecedented rate of ecological change since the 1960s driven by warming temperatures, according to the findings published Aug. 29 in Current Biology. Temperatures on the Antarctic Peninsula have increased by up to 0.56 degrees Celsuis per decade since the 1950s. Continue reading “Global warming: Moss bank core samples from Antarctic Peninsula offer new climate clues”