Northwest Passage - 2015

[DeepFrz]

StuM, that's interesting because the maximum ice extent this past winter (2015) is the lowest on record.

Along with this winter being the hottest on record and the fact that most of the old ice is gone I find your statement hard to believe. Your link provided no information.

Tuesday, March 24, 2015, 4:24 PM - Along with this past winter being the warmest on record for the globe, it now appears as though it has set another new record - one that's equally bad.

Now here is a link that does provide some information.
News - It's Official! 2015 Arctic sea ice maximum reaches lowest extent on record - The Weather Network

[DeepFrz]

And here
US Navy predicts summer ice free Arctic by 2016 | Nafeez Ahmed | Environment | The Guardian

[fryewe]

Originally Posted by DeepFrz

Your link provided no information.

Stu's link (the National Weather Service) shows that the arctic sea ice anomaly is expected to be 500,000 to 600,000 km2 during the late summer this year. That's 300nm by 600nm greater extent than average.

[StuM]

Originally Posted by DeepFrz

Along with this winter being the hottest on record and the fact that most of the old ice is gone I find your statement hard to believe. Your link provided no information.

Wow, hottest winter on record. It only averaged -25C rather than -30C above 80 North. No wonder nothing froze

I think that you will find that both average ice thickness and the percentage of multi-year versus first year ice are the highest they have been for many years - which is why the predictions are for a greater than average minimum.

[DeepFrz]

StuM's link links to a chart with no meaningful data to compare. Here is the link with some data.
Arctic Sea Ice News and Analysis | Sea ice data updated daily with one-day lag

[DeepFrz]

Oh, and here is some information on multi year ice.
multiyear ice | Arctic Sea Ice News and Analysis

While multiyear ice used to cover up to 60% of the Arctic Ocean, it now covers only 30%. There is a slight rebound in the oldest ice (4+ years old), a remnant of the large amount of first-year ice that formed during the winter after the 2007 record minimum. However, most of that new ice has not survived through the subsequent years. The oldest ice now comprises only 5% of the ice in the Arctic Ocean. This is a slight uptick from last winter’s record low of 3%, but still far less than during the 1980s when old ice covered roughly 25% of the region.

[StuM]

Originally Posted by DeepFrz

StuM's link links to a chart with no meaningful data to compare. Here is the link with some data.
Arctic Sea Ice News and Analysis | Sea ice data updated daily with one-day lag

Of course it doesn't have data. It's a projection based on current data.

But the projected anomaly and extent are certainly more meaningful than current conditions if you are planning to be there in Aug/Sep.

Your link has NO predictive value whatsoever.

[estarzinger]

I would suggest the Canadians probably have the best grasp of this . . . Their outlook is here: http://ice-glaces.ec.gc.ca/prods/OTL...0008295715.pdf

[SailOar]

Old ice in Arctic vanishingly rare | Climate.gov

Tuesday, January 20, 2015

Each winter, sea ice expands to fill nearly the entire Arctic Ocean basin, reaching its maximum extent in March. Each summer, the ice pack shrinks, reaching its smallest extent in September. The ice that survives at least one summer melt season tends to be thicker and more likely to survive future summers. Since the 1980s, the amount of this perennial ice (sometimes called multiyear) has declined.

This animation tracks the relative amount of ice of different ages from 1987 through early November 2014. The first age class on the scale (1, darkest blue) means "first-year ice,” which formed in the most recent winter. (In other words, it’s in its first year of growth.) The oldest ice (>9, white) is ice that is more than nine years old. Dark gray areas indicate open water or coastal regions where the spatial resolution of the data is coarser than the land map.

As the animation shows, Arctic sea ice doesn't hold still; it moves continually. East of Greenland, the Fram Strait is an exit ramp for ice out of the Arctic Ocean. Ice loss through the Fram Strait used to be offset by ice growth in the Beaufort Gyre, northeast of Alaska. There, perennial ice could persist for years, drifting around and around the basin’s large, looping current.

Around the start of the 21st century, however, the Beaufort Gyre became less friendly to perennial ice. Warmer waters made it less likely that ice would survive its passage through the southernmost part of the gyre. Starting around 2008, the very oldest ice shrank to a narrow band along the Canadian Arctic Archipelago.

Recent Conditions

In September 2012, Arctic sea ice melt broke all previous records. Melt was less severe in 2013 and 2014. According to the 2014 Arctic Report Card, the less extreme melting provided an opportunity for a bit more first-year ice to become perennial ice. Between March 2013 and March 2014…

• first-year ice decreased from 78 percent to 69 percent, suggesting that a substantial portion of Arctic sea ice survived the 2013 summer melt;
• second-year ice increased from 8 to 14 percent;
• fourth-year and older ice rose from 7.2 to 10.1 percent.

Overall, the amount of perennial sea ice in March 2014 rose enough to approximate the 1981-2010 median. (Median means “middle,” as in half of the years in the record had a larger extent of perennial ice, and half had a smaller extent.)

While perennial ice increased between 2013 and 2014, the long-term trend continues to be downward, the Report Card authors stated. In 1980s, the oldest ice (fourth-year ice and older) comprised 26 percent of the ice pack; as of March 2014, it was 10%. And as the animation above shows, very old ice (say, 7-8 years or older) has become even more rare.

Animation by NOAA Climate.gov team, based on research data provided by Mark Tschudi, CCAR, University of Colorado. Sea ice age is estimated by tracking of ice parcels using satellite imagery and drifting ocean buoys.

[DeepFrz]

Stum said: I think that you will find that both average ice thickness and the percentage of multi-year versus first year ice are the highest they have been for many years - which is why the predictions are for a greater than average minimum.

So Stu, who is your preacher?

[SailOar]

National Snow and Ice Data Center

[SailOar]

Charctic Interactive Sea Ice Graph | Arctic Sea Ice News and Analysis


Current State of the Sea Ice Cover

[Rustic Charm]

Guys, can you avoid turning this thread into another climate change thread and keep it purely about the north passage.

[SailOar]

Originally Posted by Rustic Charm

Guys, can you avoid turning this thread into another climate change thread and keep it purely about the north passage.

Please note the Poster and the content of posts 1 & 3.

[DeepFrz]

Rustic Charm, talking about a North West Passage must of necessity include climate change, among other things. One such item to note is that the ice had been blown towards shore and thereby had blocked off many of the more isolated villages up there. One Canadian Ice Breaker had its mission re-tasked in order to open up harbors so that essential goods could be delivered to the communities. Any passage maker needing fuel and supplies may be out of luck.