Monday, March 24, 2008

Current Sea Ice

Plenty of commentary now out in reaction to the huge and precipitous loss this past season of the perennial sea ice. Also note that the direct removal of the perennial sea ice has been continuing, likely because so much was moved into position for removal this past summer.

As I have pointed out, this has all the earmarks of an unexpected shift in weather conditions as observed whose effects we are now discovering. The evidence so far supports a sharp loss of temperate zone heat similar to 1996 - 97 to be followed by a rebound to the pre-existing levels. All this is happening against an apparent background of slightly warming conditions.

The existing new sea ice is very vulnerable to rapid removal if we have an early spring and possibly even if we do not. It also explains why, once the Arctic is cleared of perennial ice as has happened in the past, why it remains fairly stable thereafter.

So although the world is full of alarmists, the question now is whether or not we will see any further erosion of the sea ice in the next three years. On the face of it, we will not be adding much additional ice this summer. This suggests that the northern hemisphere will possibly gain more heat against a future discharge into the Arctic.

One observation can be made. The warming effect appears real, whatever the reason, but so too the eleven year cycle tied to sunspot activity. If that holds up, then we will have a rebuild of sea ice for the next several years until another period of heat build up ending in the winter of 2018.

In the meantime, the Arctic will have the most eyeballs on it in history this summer to watch what is happening. They may end up disappointed. We are getting data variation outside of previously predicted ranges. That alone suggests that we all keep our powder dry until a few seasons have passed.

WASHINGTON: Critical Arctic sea ice this winter made a tenuous partial recovery from last summer's record melt, federal scientists said Tuesday.

But that's an illusion, like a Hollywood movie set, scientist Walter Meier of the National Snow and Ice Data Center said. The ice is very thin and vulnerable to heavy melting again this summer.

Overall, Arctic sea ice has shrunk precipitously in the past decade and scientists blame global warming caused by humans.

Last summer, Arctic ice shrank to an area that was 27 percent smaller than the previous record. This winter, it recovered to a maximum of 5.8 million square miles, up 4 percent and the most since 2003, NASA ice scientist Josefino Comiso said. It is still a bit below the long-term average level for this time of year.

"What's going on underneath the surface is really the key thing," Meier said in an interview following a news conference. What's happening is not enough freezing.

Summer Arctic sea ice is important because it's intricately connected to weather conditions elsewhere on the globe. It affects wind patterns, temperatures farther south and even the Gulf Stream, acting as a sort of refrigerator for the globe, according to scientists.

"What happens there, matters here," said Waleed Abdalati, chief ice scientist at NASA's Goddard Space Flight Center in Greenbelt, Md. "Climate for the period of human record has depended on the ice being there."

Viewing the Arctic from space via NASA satellites might make you think the Arctic ice cover is on its way back.

But more than 70 percent of that sea ice is new, thin and salty, having formed only since September, Comiso said. The more important ice is perennial sea ice that lasts through the summer, and that ice has hit record low levels.

Compared to the 1980s, the Arctic has lost more than half of its perennial sea ice and three-quarters of its "tough as nails" sea ice that is six years or older, Meier said. The amount of lost old sea ice is twice the area of the state of Texas, he said.

On top of that, a change in Arctic atmospheric pressure this winter is pushing a large amount of the valuable older ice out of the Arctic to melt, Meier said.

That means next summer when temperatures warm, expect lots of melting, the scientists said.

"We're in for a world of hurt this summer," ice center senior scientist Mark Serreze told The Associated Press. Depending on the weather, there could be as much melting this year as last, maybe more, Serreze and Meier said.

At the South Pole, in Antarctica, sea ice seems stable, even slightly above normal, the scientists reported. However, ice levels in Antarctica always are quite different from the Arctic and aren't as connected to the world's weather.

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Canada's largest research project in International Polar Year has been forced to switch gears because Arctic sea ice is disappearing faster than anyone imagined. …

The Canadian Coast Guard ship Amundsen, crammed with labs and exotic scientific instruments, arrived in the Western Arctic in October to allow researchers to carry out the first-ever investigation of the changes in ice, water and atmosphere spanning four seasons."It throws a real wrench into what we wanted to do. We're struggling to adapt," said Tim Papakyriakoi, chief scientist for the current stage of the expedition.

Scientists had intended to travel to the semi-permanent base by snowmobile from the Amundsen, which was supposed to be moored nearby, safely sheltered in the fixed ice behind an ice bridge.

The bridge normally forms every winter across 120 kilometres of the Amundsen Gulf, as drifting ice becomes trapped in a chokepoint between Nelson Head, at the southern tip of Banks Island, and Cape Perry, the nearest point on the Northwest Territories mainland.

But the bridge hasn't formed this year because ice floes are passing freely through the chokepoint into the Beaufort Sea, which is relatively unclogged because of the shrinkage in the ice pack. Scientists estimate that an unprecedented 1.3 million square kilometres of ice disappeared in the summer of 2007 from the permanent Arctic ice pack, the zone that remains ice-covered at the height of summer. - Toronto Star