Global Warming

Arctic Sea Ice

The Arctic ice cap reached its eighth-lowest extent on record at the time of year the sea ice is typically at its minimum coverage.

Scientists at the U.S. National Snow and Ice Data Center (NSIDC) said that the sea ice had set a record for the smallest winter extent earlier this year and was on track to rival the record minimum set in 2012.

But a cloudy and cooler-than-normal August across the central Arctic slowed the seasonal melting.

“It’s not going to be a staircase heading down to zero every year,” said Ted Scambos of the NSIDC. “[But] the Arctic will continue to evolve towards less ice. There’s no dodging that.”

Lost Islands

Rising ocean levels in the South Pacific have swallowed at least eight low-lying islands in the Solomon Islands and Micronesia, where sea levels have risen by about half an inch each year since the early 1990s.

Australian researchers conducted coastal surveys, analyzed satellite data and spoke with island residents before making the conclusion. They found six of the islands went underwater between 2007 and 2014.

Global Warming

Fast-melting Arctic – Cause and Effects

International researchers embarked on a month-long, 10,000 kilometer (6,200-mile) journey to document the impact of climate change on the forbidding ice and frigid waters of the Far North

Glaciers, sea ice and a massive ice sheet in the Arctic are thawing from toasty air above and warm water below. The northern polar region is heating up twice as fast as the rest of the planet and that’s setting off alarm bells.

“The melting of the Arctic will come to haunt us all,” said German climate scientist Stefan Rahmstorf.

While global leaders set a goal of preventing 2 degrees Celsius (3.6 degrees Fahrenheit) of man-made warming since pre-industrial times, the Arctic has already hit that dangerous mark. Last year, the Arctic Circle was about 3.6 degrees (6.5 degrees Fahrenheit) warmer than normal.

CAUSES OF WARMING

The Arctic is mostly ocean covered with a layer of ice; changes from ice to water often kick in a cycle that contributes to global warming.

Sea ice is white and it reflects the sun’s heat back into space. But when it melts, it’s replaced with dark ocean that strongly absorbs it, said former NASA chief scientist Waleed Abdalati, who heads the environmental research program at the University of Colorado.

That heat gets transferred back up to the atmosphere in the fall and winter. As that happens, water vapor — a greenhouse gas — hangs around, trapping more heat. More clouds form around that time, also acting as a blanket, said Mark Serreze, director of the National Snow and Ice Data Center in Boulder, Colorado.

ROLE OF WINTER

Winter is crucial. Three times in the past two cold seasons, air temperatures near the North Pole were near or even a shade above freezing. That’s about 50 degrees warmer than it should be. From last November through February, Barrow, Alaska — the northernmost U.S. city — was 7 degrees Celsius (13 degrees Fahrenheit) warmer than the 20th century average, and much of the Atlantic Arctic off Norway and Greenland was as hot.

Warm winters weaken sea ice, which floats on the ocean surface. It’s supposed to recover, spread more across the Arctic and get thicker in the winter so it can withstand the warmth of the summer. But a warmer winter means less protection when the heat hits.

In September 2016, the time of year the spread of ice across the Arctic is at its lowest, Arctic sea ice was the second lowest day on record, about 40 percent below the lowest day measured in 1979 when satellite records started. Between those two days 37 years apart, the Arctic lost enough sea ice to cover Alaska, Texas and California combined.

Then it didn’t grow back that much this winter, setting record low amounts from November through March, when sea ice reaches its peak spread.

BEYOND THE ARCTIC

Of all the global warming warning signs in the Arctic, “it is the sea ice that is screaming the loudest,” Serreze said.

That’s a problem because a growing body of studies connects dwindling sea ice to wild weather. The reduced winter sea ice interacts with warmer oceans to change conditions in the air that then triggers a potent noticeable shift in the jet stream, the giant atmospheric river that controls much of our weather, said Rutgers University climate scientist Jennifer Francis. This theory is still debated by scientists, but increasingly more researchers are agreeing with Francis.

It’s not just sea ice on the decline. Glaciers in the Arctic are shrinking. And the massive Greenland ice sheet is slowly but steadily melting and that can add a big dose to sea level rise. Since 2002, it has lost 4,400 billion tons (4,000 billion metric tons) of ice.

Then there’s the Arctic carbon bomb. Carbon dioxide and methane — which traps even more heat — are stuck in the permafrost in places like Alaska and Siberia.

WILDLIFE

No Arctic creatures have become more associated with climate change than polar bears. The U.S. Fish and Wildlife Service estimated in January that about 26,000 specimens remain in the wild. Population counts of polar bears are notoriously difficult, and researchers are unsure how much their numbers have changed in recent years. But the Fish and Wildlife Service warned that melting sea ice is robbing the bear of its natural hunting ground for seals and other prey.

While some polar bears are expected to follow the retreating ice northward, others will head south, where they will come into greater contact with humans — encounters that are unlikely to end well for the bears.

The walrus, for example, may spend more time on the mainland. They’re very prone to disturbance so that’s not a good place for walrus to be.

Alarms bells are ringing about the future of the red king crab — a big earner for Alaska’s fishing industry — because rising levels of carbon dioxide, a driver of global warming, are making oceans more acidic. Scientists found that juvenile crabs exposed to levels of acidification predicted for the future grew more slowly and were more likely to die.

Algae that cling to the underside of sea ice are also losing their habitat. If they vanish, the impact will be felt all the way up the food chain. Copepods, a type of zooplankton that eats algae, will lose their source of food. The tiny crustaceans in turn are prey for fish, whales and birds.

Meanwhile, new rivals from the south are already arriving in the Arctic as waters warm. Orca have been observed traveling further north in search of food in recent years, and some wildlife experts predict they will become the main seal predator in the coming decades, replacing polar bears.

Humans are also increasingly venturing into the Arctic in search of untapped deposits of minerals and fossil fuels — posing a threat to animals. The potential for oil spills from platforms and tankers operating in remote locations has been a major cause for concern among environmentalists since the 1989 Exxon Valdez disaster off Alaska killed a quarter of a million seabirds, as well as hundreds of seals and sea otters.

Global Warming

Early Collapse of Arctic Sea Ice

Earth’s already-beleaguered northern icecap suffered another blow this month with the early collapse of a barrier that kept some of Arctic’s most durable ice in place.

The ice arch across the Nares Strait, which separates Greenland from Ellesmere Island in Canada’s far northeast, gave way two months earlier than usual, said Laurence Dyke, a paleoglaciologist at the Geological Survey of Denmark and Greenland.

“On May 10, this arch disintegrated, leaving the oldest and thickest sea ice in the Arctic vulnerable to being swept south where it will melt away,” Dyke told Seeker. “Over the last two weeks, the area of broken ice has expanded massively to the north, and lots of Arctic sea ice is flowing southwards through the Nares Strait.”

The channel and the Lincoln Sea, at the northern tip of Greenland, are normally covered by a sheet of ice several meters thick until around July, Dyke said. Usually, ice sheets that cover the strait are anchored to land and don’t move, blocking the passage of sea ice through the strait.

But as heat-trapping fossil-fuel emissions like carbon dioxide build up in the atmosphere, the Arctic is warming twice as fast as the rest of the globe. And this year, land-anchored ice in the strait failed to form amid the record warmth and record low sea ice coverage recorded across the Arctic. That left only an arch of ice at the northern end of the strait, where it joined the Lincoln Sea — the structure that gave way earlier this month.

“This is especially important as the Lincoln Sea contains the last bastion of old, thick multi-year sea ice,” Dyke said.

This image shows the boundary between permanent and seasonal sea ice in the Arctic Ocean, northwest of Greenland

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Global Warming

Arctic Alarm

Temperatures around the North Pole were up to 36 degrees Fahrenheit above normal during November, alarming researchers who say the warmth could lead to even more record lows of Arctic sea ice next year.

“These temperatures are literally off the charts for where they should be at this time of year,” said Rutgers University researcher Jennifer Francis. “It is pretty shocking.”

Temperatures rose sharply this month despite the lack of sunlight experienced at the beginning of the five months of the Arctic winter night.

This was accompanied by Arctic sea ice being at its lowest coverage ever recorded during November.

Wildlife

Alaska Polar Bears Now Live on ‘Treadmill’

An acceleration in the movement of the Arctic’s sea ice is presenting yet another climate change challenge to polar bears, making them work harder and travel farther just to stay in the same place, according to new research.

The animals have historically just rested beside holes in the ice as they waited for seals to emerge and become their next meal.

But the thinning Arctic sea ice is now drifting more quickly to the west, forcing the bears to become more active to compensate for the movement of the ice.

“In order for an Alaskan polar bear to remain an Alaskan polar bear, it must walk farther or faster to the east on the ‘treadmill,’ or it will end up in Russia,” explained U.S. Geological Survey wildlife biologist David Douglas.

Polar bear waiting for a seal to emerge from a hole in the Arctic sea ice pack.

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Global Warming

Arctic Sea Ice Melt Season Getting Longer

The summer melt season for Arctic sea ice has lengthened by a month or more since 1979, a new study finds.

The primary culprit is a delayed fall freeze-up — the autumn chill when sea water freezes into ice — but the fallout remains the same: the Arctic ice cap is stuck in a vicious feedback loop betwixt its warming environment and melting ice, researchers reported Feb. 4 in the journal Geophysical Research Letters.

The Arctic is one of the fastest warming places on Earth. Temperatures here are rising twice as fast as the global average. As the atmosphere warms, the Arctic ice cap has shrunk by 12 percent per decade since 1978, when scientists started tracking ice with satellites, according to NASA. The seven lowest September ice extents (a measure of the total ice cover) have been in past 10 years, including 2013.

As the ice cover gets smaller, the amount of heat absorbed by the Arctic Ocean rises. Bright, white ice reflects most of the sun’s energy, but the darker ocean water soaks it up.

“The ocean has gained so much heat it takes a while to release it,” said lead study author Julienne Stroeve, a senior scientist at the National Snow and Ice Data Centre in Boulder, Colo. “That’s delaying the autumn freeze-up.”

In the past decade, the additional heat stored in the upper ocean has increased Arctic sea surface temperatures by 0.9 degrees to 2.7 degrees Fahrenheit (0.5 to 1.5 degrees Celsius), Stroeve and her colleagues report. These warmer ocean temperatures prolong the summer melt season because the ocean must fall below about 29 F (minus 1.9 C) before new sea ice forms.

 

In the Kara, Laptev, East Siberian, Chukchi and Beaufort seas, the fall freeze now comes between six and 11 days later each decade since 1979. The researchers found a similar trend in the East Greenland and Barents seas, where the fall freeze may now be delayed by as much as 40 days per decade.

Oil and gas companies are already exploiting this delay by pushing for drilling leases that allow extraction and exploration well into autumn, Stroeve said. But year-to-year ice conditions can still vary dramatically.

Stroeve notes that while the overall trend is for less sea ice and a longer summer melt season, within the Arctic, ocean and weather conditions can influence how much ice is present. For instance, ice cover in the Bering Sea has increased by 20 percent in recent years, the study finds. Winds pushing sea ice south into the Bering Sea may be the cause, though scientists are still debating the reasons for the added ice cover here.

Stroeve plans further work to investigate whether the spring warming is caused by an increase in atmospheric moisture, which means more clouds and solar radiation absorption, or whether warm air coming from the south plays a role. She also hopes to track ice thickness. In the 1980s, 70 percent of the Arctic ice cap was thick, multiyear ice, which survives the summer melting. By the end of 2012, less than 20 percent of the ice cap was multiyear ice — most of the ice cover was seasonal ice, only a year old. The thinner seasonal ice melts faster.

Environment

Historic Cargo Shipped Across Northwest Passage

A Danish-owned cargo ship carried a 73,500-ton load of coal through northern Canada’s Northwest Passage in September, making it the first such bulk carrier in history to navigate the Arctic route.

The Nordic Orion left Vancouver on Sept. 17 en route to Finland on a shortcut that saved the owners nearly $200,000 in costs and trimmed about 1,000 nautical miles off the voyage.

The ship was also able to carry about 25 percent more coal since the depth of the Panama Canal, through which it normally would have passed, is too shallow for such a bulky load.

Despite this past summer’s more limited Arctic sea ice melt, a growing number of shippers are looking to use the Northwest Passage in the years ahead as the Arctic becomes more ice-free.

Edward Coll, CEO of Bulk Partners, which owns the vessel, said that beyond saving money with this single shipment, it was about making history.

“We would have done it just to do it, to pioneer it,” said Coll.

The ship was said to have encountered only one small choke point during its trip across Arctic Canada, around Baffin Island.

But the captain said the most dangerous portion of the voyage was off the western coast of Greenland, where icebergs littered the ocean.

The hardened hull of the Nordic Orion allowed it to navigate through areas of relatively thin ice.

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Global Warming

Walrus come ashore in Alaska as global warming decimates sea ice

For the Pacific walrus, global warming is undeniable.

An estimated 10,000 walrus have come ashore on Alaska’s northwest coast, the National Marine Fisheries Service reported, as the sea ice the animals normally rely on to rest continues to melt at alarming rates.

Since 2007, government scientists have tracked numerous large walrus “haulouts” in Alaska and this one began last week.

Walrus typically use ice in the Chukchi Sea upon which to rest, and feed on clams and other prey. Over the past decade, however, they have been forced to come ashore more frequently as global temperatures have continued to rise.

As of September 2012, sea ice reached its lowest square area since measurements began in 1979, Physics Today reported, and represented 55% less coverage than was measured in 1980.

According to the Fisheries Service, that’s very bad news for the walrus, whose shift in habitat “will expose all individuals, but especially calves, juveniles and females, to increased levels of stress from depletion of prey, increased energetic costs to obtain prey, trampling injuries and mortalities, and predation.”

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Global Warming

Arctic Sea Ice Closes In on Summer Low

The Arctic icepack appears to have reached its summer low this week. The annual summer melt season shrank the polar ice cap down to 5.10 million square kilometres (2.00 million square miles) on Sept. 16, according to the National Snow & Ice Data Centre (NSIDC) in Boulder, Colo. Now, NSIDC scientists are tracking the Arctic icepack’s shifting boundaries via satellite to confirm whether the Sept. 16 extent was the minimum, a spokeswoman for the research centre said. The ice can wax and wane before heading into the fall refreeze.

This year saw much more ice cover than 2012, which set an all-time record for the lowest summer ice extent. The Northwest Passage was closed for the first time since 2007. But if Sept. 16 was the summer low, then 2013 was still a sixth place finisher for the lowest amount of summer ice since record-keeping started in the Arctic 30 years ago. And the overall volume of ice — a measure of its thickness — continues to decrease as well.

Climate models predict that climate change will cause large variations in the summer ice from year to year, according to a statement from the NSIDC. This year, cool summer weather in the Arctic helped the ice stick around for the summer, the NSIDC said. Air temperatures were colder than average in the Arctic, which helps retain a thin layer of ice, increasing the overall ice extent.

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Environment

Arctic Cyclone Tears Up Sea Ice

Arctic scientists are watching in awe this week as a raging summer cyclone tears up what could become a record amount of rotting northern sea ice.

Arctic cyclones are driven by low-pressure systems in which winds of up to 100 km/h blow counter-clockwise in a spiral more than 1,000 kilometres across. They occur in both winter and summer, but are usually stronger in winter. Cyclones are not unusual in the Arctic, but seem to be changing in recent years. “These cyclones are not getting more frequent, but they are getting deeper — which means stronger.”

And they’re getting harder on sea ice, which they break up through wave action associated with high winds and through rainfall, which darkens the ice and makes it absorb more solar energy. The storms also bring up water from the depths, which is actually warmer than surface water.

Cyclones can destroy large amounts of ice very quickly. “In 2009, we actually documented one of these events in which large, multi-year ice floes – Manhattan-sized – broke up in a matter of minutes.” Last year, a particularly powerful cyclone is thought to have wiped out 800,000 square kilometres of ice. That contributed to record low sea-ice levels at the end of the 2012 melt year.

This year’s storm over the Beaufort Sea formed about mid-week and is expected to die out on the weekend. It isn’t as strong as last year’s, but the ice is thinner and weaker. As well, the ice has already been pummelled by earlier storms. “The effects of (the storm) are nowhere near what we saw last August. But because the ice is thinner and it’s already been pre-conditioned, and because there’s less volume, it’s much more vulnerable to impacts from this sort of thing.”

The ice is getting so weak that new categories have had to be created for it. “We have a whole new class of sea ice in the Arctic, which we’re calling ‘decayed ice. We started seeing it in 2009. It’s extremely weak.” Changing sea-ice cover is increasingly being linked to southern weather patterns. The jet stream, which strongly influences weather at mid-latitudes, is driven by temperature differences between the Arctic and the equator, a difference that shrinks with the sea ice. Ice coverage is slightly about last year’s record low but still well below the 30-year average.

Much remains unknown about the role of Arctic cyclones in the annual freeze-thaw cycle. Back when the sea was thick and lasted for years, cyclones tended to spread the ice out and actually increase its extent. Now, when ice gets spread out, it simply breaks up and disappears. “As our ice cover has thinned, some of our old rules are changing…This year has been very stormy. The month of August is definitely one to watch in the Arctic.”

Environment

Less Ice Equals More Seal Strandings on US Coast

Harp seals mate and rear their young on the sea ice off the east coast of Canada in the spring and move north as the weather warms. But increasing numbers of seals are ending up stranded along the U.S. East Coast, as far south as the Carolinas, far away from where they should be at this time of year.

Harp seal

Environment

Russia To Evacuate Arctic Station Over Melting Ice

A Russian drifting Arctic research station is to be evacuated because the ice field around it is melting, the environment ministry in Moscow reports. The ministry has ordered an evacuation plan to be drawn up within three days for North Pole 40 and its staff of 16. It is sending a nuclear-powered icebreaker to help move the station, located near Canada’s economic zone.

Arctic ice melted at record speed in 2012, one of the warmest years on record. The research station will be relocated to Bolshevik Island in the Severnaya Zemlya archipelago.

Global Temperature Extremes

The week’s hottest temperature was 122.0 degrees Fahrenheit (50.0 degrees Celsius) at Jacobabad, Pakistan.

The week’s coldest temperature was minus 102.6 degrees Fahrenheit (minus 74.8 degrees Celsius) at the U.S. Amundsen-Scott South Pole Station.

Temperatures were tabulated from the more than 10,000 worldwide synoptic weather stations. The United Nations World Meteorological Organization sets the standards for weather observations, and provides a global telecommunications circuit for data distribution.

Environment

Arctic Ice Loss May Drive Extreme Weather Patterns

Several researchers say that warming conditions in the Arctic may be weakening jet stream currents and causing extreme weather systems to linger in northern mid-latitudes.

Climate scientists have blamed melting sea ice for causing extreme winter in North America and Europe during this winter. Thickness of the ice is also a concern among the environmental scientists.

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The jet stream is a band of very strong winds that blow from west to east, several miles above the earth’s surface. Normally, these powerful winds push weather systems around, preventing them from staying in one place for very long.

However, the loss of sea ice in recent decades has allowed Arctic waters to absorb more heat energy from the sun, which has in turn heated the atmosphere above the water.

This heating influences atmospheric pressure and appears to be slowing the westerly jet stream. Instead of flowing quickly and in a relatively straight line, like a river down a mountain, the winds mimic a slower, meandering river.

Arctic sea ice is referred to as the planet’s air conditioner, due to its influence on global temperatures. Last year, Arctic sea ice reached its lowest level in the satellite age.

This rate of sea ice loss is faster than what models predicted. Now, some experts say, the Arctic could experience a nearly ice-free summer by 2020.