Arctic Ice Watch

PS_RalphW · Post by **PS_RalphW** » 02 Jun 2016, 09:34

BY open water I meant that it was almost possible to sail from one NWP to the Pacific.

There are only a few miles where the path is blocked by solid ice
http://forum.arctic-sea-ice.net/index.p ... 0141;image

There are areas of low concentration ice near the bering strait and the NWP itself, but they would be navigable.

vtsnowedin · Post by **vtsnowedin** » 02 Jun 2016, 20:10

PS_RalphW wrote:BY open water I meant that it was almost possible to sail from one NWP to the Pacific.

There are only a few miles where the path is blocked by solid ice
http://forum.arctic-sea-ice.net/index.p ... 0141;image

There are areas of low concentration ice near the bering strait and the NWP itself, but they would be navigable.

I don't know what you mean by "one NWP" Are you talking about Pond inlet or Cape Dorset?
There is some open water at point Barrow but there is that annoying section "O" on the ice chart which is about 50 KM of 90%plus ice. After that there is another 500KM of open water around Tuktoyaktuk but halfway to Kugluktut you hit 100% fast ice and will have to wait for it to break up before going the next 2000KM past Cambridge Bay and Resolute and on to Pond inlet. Red and grey areas on the chart are a nogo at this time.

PS_RalphW · Post by **PS_RalphW** » 08 Jun 2016, 13:00

The latest PIOMAS figures are out, and by a very narrow margin ice volume is at a record low for May, to go with record low area and extent numbers.

However, it is unlikely to remain in first place, at least for volume, as 2012 saw unprecedented melt in June, and it is not yet being matched this year.

The weather has moved into a low pressure theme over the arctic, and this has reversed ice drift, and introduced widespread cloud, and as a result ice extent decline has almost stalled, and area decline has slowed as well. The forecast for the next 10 days is similar.

However, it has also introduced very warm air from the Siberian coast over the ice, creating a lot of surface melt and melt ponding on the relatively thick and fast ice in that area, and the fractured ice in the Beaufort Sea is slowly dispersing into the sun warmed water. There is a lot of potential for rapid melt in the weeks ahead.

Comparing the PIOMAS ice distribution against the record years of 2011/12, there is thicker ice close to the Canadian islands and the Siberian coast, but thinner or entirely missing elsewhere. The Canadian ice is not going to melt out, but the Siberian ice probably will, if this weather pattern continues for a few weeks. Overall, a record ice melt this summer looks to be about 50/50, with a significant chance of an ice free North Pole.

vtsnowedin · Post by **vtsnowedin** » 09 Jun 2016, 11:31

Average temperatures for the area North of 80 degree North latitude rose above Zero C yesterday. This is within a day or two of the 1952 to 2008 mean.
http://ocean.dmi.dk/arctic/meant80n.uk.php

PS_RalphW · Post by **PS_RalphW** » 22 Jun 2016, 16:35

Low pressure has dominated over the arctic for the last 2 weeks. As predicted, this has sharply reduced the rate of decline for both area and extent measurements, in the same 2 weeks that in 2012 that saw a massive decline in both.

As a result, ice area is now running very close to 2012 numbers, and the 1M sq km lead in ice extent has been reduced by over 90%.

The cloudy weather has reduced the level of melt ponding on the surface of the ice, sharply reducing the probability of a record summer melt.

The reversal of wind direction has sharply reduced ice export to the East Greenland Sea and ice has drifted back across much of the Beaufort Sea, with large flows slowly dispersing into the open water.

In the last few days, the rate of decline has returned to be similar to 2012 levels, so for now we still have record low ice extent, and possibly area.

What happens next depends on the weather. At the moment the forecasts are showing little consensus.

One effect of the recent weather has been relatively high pressure and clear skies over Greenland, resulting in high levels of surface melt on the land ice sheet.

PS_RalphW · Post by **PS_RalphW** » 06 Jul 2016, 14:20

Another two weeks and finally the weather in the Arctic is beginning to get more interesting.

Ice extent figures have continued to drop at a fair rate and are very close or below the previous record years of 2010 and 2012 at this time. Ice area has fallen into about 3rd place behind those years.

Preliminary figures for June PIOMAS ice volume probably put 2016 in third place, about 500 Cubic Km behind 2012.

There is a lot of ice left in Hudson Bay, this is normally melted by this date, so that is ice that can be discounted from the summer minimum.

A stronger low pressure system is near the North Pole, which will churn up the ice in the coming days, and high pressure is building in the Beaufort, with a heatwave over northern Canada and Alaska, so we can expect the widely dispersed ice floes in that sea to be badly affected in the next few days.

A good chance the NW passage will be navigable son.

vtsnowedin · Post by **vtsnowedin** » 07 Jul 2016, 12:45

PS_RalphW wrote:
A good chance the NW passage will be navigable son.

Be a couple of weeks yet don't you think?
https://lance.modaps.eosdis.nasa.gov/im ... 6188.terra
http://ice-glaces.ec.gc.ca/prods/WIS56C ... 945748.pdf

UndercoverElephant · Post by **UndercoverElephant** » 24 Jul 2016, 13:38

http://www.independent.co.uk/environmen ... 47846.html

"It’s no news that Greenland is in serious trouble — but now, new research has helped quantify just how bad its problems are. A satellite study, published last week in the journal Geophysical Research Letters, suggests that the Greenland ice sheet lost a whopping 1 trillion tonnes of ice between the years 2011 and 2014 alone. And a big portion of it came from just five glaciers, about which scientists now have more cause to worry than ever. "

vtsnowedin · Post by **vtsnowedin** » 24 Jul 2016, 15:51

UndercoverElephant wrote:http://www.independent.co.uk/environmen ... 47846.html

"It’s no news that Greenland is in serious trouble — but now, new research has helped quantify just how bad its problems are. A satellite study, published last week in the journal Geophysical Research Letters, suggests that the Greenland ice sheet lost a whopping 1 trillion tonnes of ice between the years 2011 and 2014 alone. And a big portion of it came from just five glaciers, about which scientists now have more cause to worry than ever. "

Really people? Please do the math.
If they are accurate the rate of melt is some 287 billion tonnes of ice a year. A cubic meter of ice has a mass of 1.0 tonne. A cubic kilometer of ice has a mass of 1 billion tonnes.
There are 2,850,000 cubic kilometers of ice in the Greenland cap.
2,850,000/ 287= 9,930 years to melt it all at current rates.
If it all melts the projection for sea level rise is 7.2 meters.
7.2/ 9930=0.72 millimeters a year.
https://en.wikipedia.org/wiki/Greenland_ice_sheet

woodburner · Post by **woodburner** » 24 Jul 2016, 17:41

On Powerswitch we never let facts get in the way of a good story.

Little John · Post by **Little John** » 24 Jul 2016, 18:27

Speak for yourself woodburner

Post by **clv101** » 24 Jul 2016, 20:39

vtsnowedin wrote:
UndercoverElephant wrote:http://www.independent.co.uk/environmen ... 47846.html

"It’s no news that Greenland is in serious trouble — but now, new research has helped quantify just how bad its problems are. A satellite study, published last week in the journal Geophysical Research Letters, suggests that the Greenland ice sheet lost a whopping 1 trillion tonnes of ice between the years 2011 and 2014 alone. And a big portion of it came from just five glaciers, about which scientists now have more cause to worry than ever. "
Really people? Please do the math.
If they are accurate the rate of melt is some 287 billion tonnes of ice a year. A cubic meter of ice has a mass of 1.0 tonne. A cubic kilometer of ice has a mass of 1 billion tonnes.
There are 2,850,000 cubic kilometers of ice in the Greenland cap.
2,850,000/ 287= 9,930 years to melt it all at current rates.
If it all melts the projection for sea level rise is 7.2 meters.
7.2/ 9930=0.72 millimeters a year.
https://en.wikipedia.org/wiki/Greenland_ice_sheet

Well... a cubic meter of ice isn't a tonne, it's more like 920 kg. One thing we can be sure of is that it won't melt 'at current rates'. The ice sheet has it's head in the clouds with much of it over 2000 m. Firstly, as it melts, the surface lowers into warmer air and the melt rate increases. Secondly, the causes of surface melt (largely surface air temperature) are increasing. Warming air and lowering altitude guarantee accelerating mass loss. Then there are similar processes with marine terminating glaciers, warming water and reverse bed topography. Finally, as melting is lower the surface more around the ice sheet periphery (and wetter air is increasing snowfall in the centre) there's an increased gravitational gradient accelerating glacier flow rates.

vtsnowedin · Post by **vtsnowedin** » 24 Jul 2016, 23:53

clv101 wrote:
vtsnowedin wrote:
UndercoverElephant wrote:http://www.independent.co.uk/environmen ... 47846.html

"It’s no news that Greenland is in serious trouble — but now, new research has helped quantify just how bad its problems are. A satellite study, published last week in the journal Geophysical Research Letters, suggests that the Greenland ice sheet lost a whopping 1 trillion tonnes of ice between the years 2011 and 2014 alone. And a big portion of it came from just five glaciers, about which scientists now have more cause to worry than ever. "
Really people? Please do the math.
If they are accurate the rate of melt is some 287 billion tonnes of ice a year. A cubic meter of ice has a mass of 1.0 tonne. A cubic kilometer of ice has a mass of 1 billion tonnes.
There are 2,850,000 cubic kilometers of ice in the Greenland cap.
2,850,000/ 287= 9,930 years to melt it all at current rates.
If it all melts the projection for sea level rise is 7.2 meters.
7.2/ 9930=0.72 millimeters a year.
https://en.wikipedia.org/wiki/Greenland_ice_sheet
Well... a cubic meter of ice isn't a tonne, it's more like 920 kg. One thing we can be sure of is that it won't melt 'at current rates'. The ice sheet has it's head in the clouds with much of it over 2000 m. Firstly, as it melts, the surface lowers into warmer air and the melt rate increases. Secondly, the causes of surface melt (largely surface air temperature) are increasing. Warming air and lowering altitude guarantee accelerating mass loss. Then there are similar processes with marine terminating glaciers, warming water and reverse bed topography. Finally, as melting is lower the surface more around the ice sheet periphery (and wetter air is increasing snowfall in the centre) there's an increased gravitational gradient accelerating glacier flow rates.

While a cubic meter of ice freshly frozen on the surface is indeed closer to 915 to 920 kilograms much of the ice in the Greenland ice cap is squeezed under the weight of two to three kilometers of ice over it and is denser then liquid water. But feel free to redo your calculations using the freshly frozen fresh water specific gravity.
Then on to your next point. Yes the rate of melt is increasing most probably due to human over population and the resulting carbon and latent heat emissions. So what if the rate melting increased exponentially?
I'm tired and have more then a couple of brews under my belt so I will let you take first try on that math and check your figures in the morning.

UndercoverElephant · Post by **UndercoverElephant** » 25 Jul 2016, 02:10

clv101 wrote:
vtsnowedin wrote:
UndercoverElephant wrote:http://www.independent.co.uk/environmen ... 47846.html

"It’s no news that Greenland is in serious trouble — but now, new research has helped quantify just how bad its problems are. A satellite study, published last week in the journal Geophysical Research Letters, suggests that the Greenland ice sheet lost a whopping 1 trillion tonnes of ice between the years 2011 and 2014 alone. And a big portion of it came from just five glaciers, about which scientists now have more cause to worry than ever. "
Really people? Please do the math.
If they are accurate the rate of melt is some 287 billion tonnes of ice a year. A cubic meter of ice has a mass of 1.0 tonne. A cubic kilometer of ice has a mass of 1 billion tonnes.
There are 2,850,000 cubic kilometers of ice in the Greenland cap.
2,850,000/ 287= 9,930 years to melt it all at current rates.
If it all melts the projection for sea level rise is 7.2 meters.
7.2/ 9930=0.72 millimeters a year.
https://en.wikipedia.org/wiki/Greenland_ice_sheet
Well... a cubic meter of ice isn't a tonne, it's more like 920 kg. One thing we can be sure of is that it won't melt 'at current rates'. The ice sheet has it's head in the clouds with much of it over 2000 m. Firstly, as it melts, the surface lowers into warmer air and the melt rate increases. Secondly, the causes of surface melt (largely surface air temperature) are increasing. Warming air and lowering altitude guarantee accelerating mass loss. Then there are similar processes with marine terminating glaciers, warming water and reverse bed topography. Finally, as melting is lower the surface more around the ice sheet periphery (and wetter air is increasing snowfall in the centre) there's an increased gravitational gradient accelerating glacier flow rates.

What about "rebound" when the weight of ice has gone? Or is that too slow a process to be relevant?

woodburner · Post by **woodburner** » 25 Jul 2016, 02:25

Little John wrote:Speak for yourself woodburner

I doubt there is anyone who posts on PS who has not used information at some time, thought to be fact, that turned out to be false, or poorly researched.