About these ads

Online Arctic sea ice atlas unveiled

sgh

Tracking Arctic ice. Image courtesy NASA’s Blue Marble website.

New tool to help coastal and ocean planners in the region

By Summit Voice

FRISCO — With Arctic sea ice at an all-time record low for late January and the melt season about to begin, researchers have created a new online tool that helps put ice conditions in historical perspective. Continue reading

About these ads

Global warming: More coastal habitat for geese in Alaska due to rising temperatures, melting sea ice

sdfg

A family of black brant geese in Alaska, Photo courtesy USGS.

Some species may benefit from climate change

By Summit Voice

FRISCO — Dwindling sea ice spells trouble for polar bears and walrus colonies, but some other animals are benefiting from global warming — at least for now.

Warming temperatures have resulted in more high quality habitat for geese along the Arctic coast of Alaska, according to a U.S. Geological Survey study.

The research focused on  black brant geese that migrate by the thousands each summer to the Arctic Coastal Plain of Alaska to undergo their wing molt, during which time the birds are flightless for three weeks. This molting period requires high quality food to give the birds the energy necessary to replace worn feathers and also extensive open water areas where birds can escape from predators. Continue reading

Climate: Winds driving Antarctic sea ice growth

Global warming likely to reverse trend in coming decades

sfd

Antarctic sea ice extent has been growing the past few decades, bberwyn photo.

By Summit Voice

FRISCO — Climate scientists have long suspected that increasing winds around Antarctica have been the main cause of growing sea ice extent in the southern hemisphere, and new research from the University of Washington shows how and why that might be happening — even as overall global temperatures warm.

Global warming deniers have tried to use the growth of Antarctic sea as a weapon in their battle against science, but climate researchers point out that the loss of Arctic sea ice far outweighs the small increase in the southern hemisphere. And the new research suggests that, as global temperatures continue to increase, Antarctic sea ice is all but certain to start shrinking.

Overall, Antarctic sea ice has been increasing by about 1 percent annually, which has led to record sea ice extent in the region the past few years. As of September 16, Antarctic sea ice extent reached about 7.51 million square miles, a record for the date and about 3.9 percent above the 30 year average. By contrast, this year’s Arctic summer minimum ice extent is approximately 30 percent below the 30-year average. Continue reading

Climate: Parts of the Arctic getting greener

Researchers are trying to identify the consequences of dwindling sea ice. Photo courtesy University of Alaska Fairbanks.

Researchers are trying to identify the consequences of dwindling sea ice. Photo courtesy University of Alaska Fairbanks.

Study shows fundamental ecosystem changes under way

By Summit Voice

Sea ice decline is already changing some Arctic ecosystems in fundamental ways, according to University of Alaska Fairbanks scientists. As part of review team, the two researchers showed, for example, that disappearing sea ice leads to a loss of sea-ice algae, at the very base of the Arctic marine food web. Larger plankton is thriving, replacing smaller, but more nutrient dense plankton. What that means exactly is not yet understood.

“Our thought was to see if sea ice decline contributed to greening of the tundra along the coastal areas,” said Uma Bhatt, an associate professor with UAF’s Geophysical Institute. “It’s a relatively new idea.” Continue reading

Study: Declining sea ice not good for polar bears

zdsf

A detailed new study shows how declining sea ice affects polar bear migration. Photo courtesy USFWS.

Research may help explain declines in cub production and body condition

By Summit Voice

SUMMIT COUNTY — A 10-year study of polar bears around western Hudson Bay offers new clues to how the predators will cope with global warming.

The research, published in the British Ecological Society’s Journal of Animal Ecology, focused on how sea ice conditions drive polar bears’ annual migration on and off the ice.

Polar bears have adapted to the annual loss of sea ice by migrating onto land each summer. While there, they cannot hunt seals and must rely on fat reserves to see them through until the ice returns.

“The data suggest that in recent years, polar bears are arriving on shore earlier in the summer and leaving later in the autumn,” said Dr. Seth Cherry, of the University of Alberta. “These are precisely the kind of changes one would expect to see as a result of a warming climate and may help explain some other studies that are showing declines in body condition and cub production.” Continue reading

Climate: German researchers document dramatic Arctic ecosystem changes linked with melting sea ice

On a voyage

On a voyage to the central Arctic Ocean, German researchers documented significant changes to marine ecosystems linked with melting Arctic sea ice. Photo courtesy Alfred Wegener Institute.

Massive algae blooms change composition of sea floor food chain

By Summit Voice

SUMMIT COUNTY — Arctic Ocean ecosystems are sure to change in as-yet unexpected ways as sea ice continues to shrink. This summer, German Polar researchers and microbiologists documented one of those changes, observing an unprecedented bloom of ice-loving algae on patches of thin summer ice.

The researchers hypothesized three years ago that ice algae could grow faster under the thinning sea ice of the Central Arctic. This past summer’s observations support the hypothesis: The ice algae were responsible for almost half of the primary production in the Central Arctic Basin. The paper is published in the journal Science.

“We were able to demonstrate for the first time that the warming and the associated physical changes in the Central Arctic cause fast reactions in the entire ecosystem down to the deep sea,” said Lead researcher Dr. Antje Boetius, of the Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research. Continue reading

Global warming: What are the options for polar bears?

asdf

Are polar bears on the brink?

“It’s a fact that early sea ice break-up and late ice freeze-up and the overall reduction in ice pack are taking their toll.”

By Summit Voice

FRISCO — Despite reports of increases in isolated polar bear populations, the species as a whole is still imperiled by the rapid, steady rise in Arctic temperatures and shrinking areas of sea ice. Just one unexpected jump in Arctic warming trends could push the predators toward extinction, according to a new warning from a team of scientists led by University of Alberta polar bear researcher professor Andrew Derocher.

The new paper in the journal Conservation Letters is framed as a policy perspective, urging countries with polar bear populations to consider the long-term implications of climate change.

“It’s a fact that early sea ice break-up and late ice freeze-up and the overall reduction in ice pack are taking their toll,” Derocher said. “We want governments to be ready with conservation and management plans for polar bears when a worst case climate change scenario happens.” Continue reading

New study tracks emperor penguin sea ice habits

Sea ice critical for rests during long foraging treks

These are emperor penguins near the sea.
Credit: Photo credit: Katsufumi Sato (Atmosphere and Ocean Research Institute, The University of Tokyo)

By Summit Voice

SUMMIT COUNTY — Climate-related shifts in ice around Antarctica have already been implicated in the disappearance of at least emperor penguin colony, but researchers have not been sure exactly how sea ice figures in to their life cycle.

In a new study, researchers show how the birds use sea ice to rest during long foraging periods. The life cycle of the emperor penguins takes place in an exquisite balance with the rhythms of ice formation. Courtship, egg laying and incubation occur during winter, followed by hatching, brooding and crèche formation during spring and early summer. Both parents tend the chicks until they fledge, generally in late spring and early summer (November and December), when the ice breaks up into floes that drift with the wind and currents.

Unlike other species, like Adelie penguins, emperor penguins spent much more time diving for food, and only used about 30 percent of their time at sea to take short breaks to rest on sea ice. The birds did not travel for long distances on the ice, or use it for other activities. The study also suggests that these short rest periods on sea ice may help the penguins avoid predators such as leopard seals. Continue reading

Climate: Arctic sea ice expanding, but impacts from record-low levels could still be felt the next few months

Antarctic sea ice extent remains above average

Antarctic sea ice has dwindled from a record-high extent in October but remains above average for this time of year. Bob Berwyn photo.

By Summit Voice

SUMMIT COUNTY — Although Arctic sea ice cover has grown quickly the past few weeks, the extent remained below the previous record low for a full 40 days before recently climbing back to near that 2007 level on Oct. 6.

According to the National Snow and Ice Data Center, sea ice extent had grown to about 2 million square miles as of Oct. 15, which is about 1.35 million square miles below the 1979 to 2000 mean. Ice extent is growing by about 38,600 square miles per day, expanding southward at the ice edge, as well as northward from the Arctic continental coasts

Despite the rapid growth of the sea ice extent in the past few weeks, vast areas of open water remain, resulting in a massive heat transfer from the ocean to the atmosphere, with potential impacts on atmospheric circulation in high latitudes, as the heat buildup over the Arctic changes pressure gradients in the region. Continue reading

Climate: Antarctic research season starts with aerial surveys

NASA’s Operation IceBridge surveys Thwaites Glacier and Bellinghausen Sea

This NASA photo shows the calving front of Thwaites Ice Shelf looking at the ice below the water’s surface. Note how the water acts as a blue filter.

By Summit Voice

SUMMIT COUNTY — As Arctic sea ice melted away to a new record-low level this summer, global warming deniers tried to deflect attention from the meltdown by emphasizing the growth in Antarctic sea ice.

Of course, the increase in Antarctic sea ice is small compared to the loss of Arctic ice, and there are other hints that Antarctica is set to experience some major changes. In coming decades, entire ice shelves along the coast may crumble into the sea, potentially contributing significantly to sea level rise.

To measure those impending changes, NASA has been doing extensive aerial surveys in Antarctica with Operation IceBridge, and this year’s flying season began productively with a land ice survey of Thwaites Glacier and a sea ice flight over parts of the Bellingshausen Sea. Continue reading

Follow

Get every new post delivered to your Inbox.

Join 7,360 other followers