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Arctic Sea Ice Extent, Area, and Volume


ORH_wxman
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43 minutes ago, chubbs said:

Looking more and more like a 2 horse race

Arctic_Graph_full.png

2010 (not listed on the graph) was actually the leader right now....but then it stalled starting tomorrow. But I think this year def has a better chance than 2010 since the weather forecast remains favorable for big ice losses over the next week.

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This is where our 'Banker ice' , to the North of Greenland, shows us that it will not be the last of the ice left in the basin.

The clearing out of the grounded 'fast ice' , along Greenlands North shore and NE tip ( back in 2012?) leaves nothing to slow/stop the export of the smaller floes that the ice north of Greenland consists of today.

Some folk may well be surprised at just how mobile that ice area can become given the correct forcing?

And still the 'high melt' forcing continues over swathes of the basin. The folk who only work with the numbers may be wholly ignorant of the losses in ice volume the June 'mid month' PIOMAS numbers meant in terms of thinning of the pack overall. We have very little 2m ice left in the basin presently and a lot clumped around the 1m thickness mark. To me , should we see a continuation throughout the high insolation period, all that ice is done.

If we then look at a map of the ice we see it is the N of Greenland that holds the ice not progged to melt, well, not in-situ anyway....... should it take a shove toward the Atlantic then all bets are off!!!.......

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On 6/18/2019 at 9:55 AM, Weatherdude88 said:

NSIDC sea ice extent is now the 7th lowest value for 6.17, with a value of 10.696 millions of kilometers squared. 2019 has greater sea ice extent for the date, than 2010, 2011, 2012, 2016, 2017, and 2018.

 

And you lost.

Upcoming pattern looks brutal for Arctic, and if this pattern lasts through the summer like I think it will, then 2012 could go down the tubes.

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4 hours ago, Gray-Wolf said:

This is where our 'Banker ice' , to the North of Greenland, shows us that it will not be the last of the ice left in the basin.

The clearing out of the grounded 'fast ice' , along Greenlands North shore and NE tip ( back in 2012?) leaves nothing to slow/stop the export of the smaller floes that the ice north of Greenland consists of today.

Some folk may well be surprised at just how mobile that ice area can become given the correct forcing?

And still the 'high melt' forcing continues over swathes of the basin. The folk who only work with the numbers may be wholly ignorant of the losses in ice volume the June 'mid month' PIOMAS numbers meant in terms of thinning of the pack overall. We have very little 2m ice left in the basin presently and a lot clumped around the 1m thickness mark. To me , should we see a continuation throughout the high insolation period, all that ice is done.

If we then look at a map of the ice we see it is the N of Greenland that holds the ice not progged to melt, well, not in-situ anyway....... should it take a shove toward the Atlantic then all bets are off!!!.......

The sea ice north of Greenland is projected to be the last to go.

https://ccin.ca/ccw/seaice/future

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I do not think we believe 'North of Greenland' as the refuge we once did?

In 2012 we saw ice modelled at 5m  thick go over that summer ( and the MacKenzie delta turn positively mediterranean!) then , more recently we saw the 'Feb lift off' leaving open water along that strip in mid winter.

If anything 'N. Greenland ' is wherer ice waits to be exported?

If Nares has been open all winter then the lincoln Sea supply of thick ice is depleted so eventually we have no ice to replace that going down the Fram.

The upcoming Di-pole might be an interesting watch to see how far into the body of the pack ice moves toward Fram?

As for Beaufort/ESS/Laptev/Kara?........well, just shows what thin fragmented ice acts like when impacted by either WAA from the land or warmed river waters.

Another big loss day today opening more water for ice to flow into ( and not impact the numbers much if they were already over 15% ice covered) but that water is ever warmer as the season progresses and the more isolated the floe the more energy that water pours into it......leaving more open water for ice to flow into.......rinse and repeat

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Final June NSIDC-adjusted area numbers are in, and we're currently 2nd lowest on record behind 2012 though 2007 and 2010 were very close to 2019 as well. What this means is that this year has an excellent chance to finish in the top 3 lowest extent/areas on record.

Here are the top 5 lowest:

2012 (6.53 million sq km)

2019 (6.76 million)

2010 (6.77 million)

2007 (6.81 million)

2016 (6.94 million)

 

Does this year have enough of a good start to set a new record? Most likely not. The numbers do not support it. That doesn't mean 0 chance though like more recent years. But we will have to set a new record for area loss between now and the minimum to get there...however, we don't have to set it by much....only about 40k. If we melt 40k more area than 2016 from here on out, we'll set a new minimum area record.

The average 2007-2018 loss from July 1st onward was 4.13 million sq km. That would leave 2019 at 2.63 million sq km of ice at the minimum for area. The 2012 record sits at 2.22 million sq km of ice which means in order to set a new recrod, we need to lose 4.56 million sq km of ice area. 2016 is the current record of ice area loss from this point forward losing 4.52 million sq km. So as stated above, we will need to beat this by about 40k or more to pass 2012 at the minimum. That is going to be about 2 standard deviations or even a little more for losses. So I'd put the chances of setting a new record at about 5%. Again, this is for area only. Not extent.

Extent is a little tougher since things like compaction can occur that affect extent a lot more than it affects area. Still, it will be hard to set the extent record as well. We might have a slightly greater than 5% chance at setting the extent record since 2012 wasn't extremely compacted.

 

 

Getting back to area, below is a histogram of what would happen to 2019 if we followed all area losses from previous years....so for example, if we followed 2018 area losses from this point forward, we would finish with an area minimum of just over 2.50 million sqkm:

 

2019_min_prediction.png.76798fb41b0c7c0de844a4bf1bfe089c.png

 

 

 

 

So given the information above, I am going to predict a minimum area of 2.60 million sq km +/- 200k (2.4-2.8 for a range). I will set a minimum NSIDC extent of 3.8 million sq km +/- 200k (3.6-4.0 as a range). Neither of these ranges include the 2012 record...I don't believe we will quite make it. But this year at least has an outside shot unlike previous recent years, so at least there is a reason to track closely.

 

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Looks like June finished with the 2nd lowest extent on record behind 2016.

https://mobile.twitter.com/ZLabe/status/1145720975402553344

Average June #Arctic sea ice extent was the 2nd lowest on record. It was 1,230,000 km² below the 1981-2010 average.

 https://mobile.twitter.com/AlaskaWx/status/1145790324465254400

Chukchi Sea average ice extent in June was the lowest of record in 41 years of daily passive microwave data from NSIDC.

That means an additional (compared to normal) area the size of Florida was open water being heated by the sun instead of ice.

 

 

 

 

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16 hours ago, bluewave said:

Looks like June finished with the 2nd lowest extent on record behind 2016.

https://mobile.twitter.com/ZLabe/status/1145720975402553344

Average June #Arctic sea ice extent was the 2nd lowest on record. It was 1,230,000 km² below the 1981-2010 average.

 https://mobile.twitter.com/AlaskaWx/status/1145790324465254400

Chukchi Sea average ice extent in June was the lowest of record in 41 years of daily passive microwave data from NSIDC.

That means an additional (compared to normal) area the size of Florida was open water being heated by the sun instead of ice.

 

 

 

 

I think many folk are unaware of just what a shift such a change is?

We go from 90%+ of the incoming solar to the 'dark water' accepting 90%+ of all incoming solar.......but there's more!

That <10% if solar over the ice needs to spend 70 cals of energy to melt 1cm 3 of ice

When the ice has gone then over 90% of that incoming goes into warming water. If we put the 70 cals into a q1cm cube of water it would raise the temp to 70c!!!

So 9 times as much energy arriving at the surface and 1cm of ice warmed 1c for every 1 cal poured into it!

I view it as 'new energy' in our climate system and can see ,full well, why Jen Francis sees it making such havoc at seasons end when that energy is released back into the atmosphere prior to the ocean freezing!

" When the ice goes it will just , all of a sudden,go"

With the pack's average thickness at max. around 2m we have the potential to see, over late July/Aug, a lot of ice 'suddenly go' as accrued melt momentum and warmed ocean takes out all ice of similar thickness over a short period of time ( FY ice?)

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43 minutes ago, Gray-Wolf said:

I think many folk are unaware of just what a shift such a change is?

We go from 90%+ of the incoming solar to the 'dark water' accepting 90%+ of all incoming solar.......but there's more!

That <10% if solar over the ice needs to spend 70 cals of energy to melt 1cm 3 of ice

When the ice has gone then over 90% of that incoming goes into warming water. If we put the 70 cals into a q1cm cube of water it would raise the temp to 70c!!!

So 9 times as much energy arriving at the surface and 1cm of ice warmed 1c for every 1 cal poured into it!

I view it as 'new energy' in our climate system and can see ,full well, why Jen Francis sees it making such havoc at seasons end when that energy is released back into the atmosphere prior to the ocean freezing!

" When the ice goes it will just , all of a sudden,go"

With the pack's average thickness at max. around 2m we have the potential to see, over late July/Aug, a lot of ice 'suddenly go' as accrued melt momentum and warmed ocean takes out all ice of similar thickness over a short period of time ( FY ice?)

The record Chukchi SST warming has implications for the entire Arctic.

https://www.newscientist.com/article/2178160-a-warm-water-time-bomb-could-spell-disaster-for-arctic-sea-ice/

The Arctic is in hot water, literally, following the discovery that heat has been accumulating rapidly in a salty layer of the Arctic Ocean 50 metres down. Currently, it’s being held at that depth by a less dense layer of freshwater overhead, but if the two layers start to mix it could melt all seasonal sea ice, accelerating the already-rapid loss of polar ice cover.

Researchers discovered the heat time-bomb after analysing publicly available data on ice cover, and at different depths on sea temperature, heat content and saltiness over the past three decades. The data was gathered around the Canadian Basin, a major basin of the Arctic Ocean fed by waters from the North Chukchi Sea, just north of the Bering Strait between Alaska and Siberia.

Over this timespan, the heat content of the salty layer doubled, from 200 to 400 million joules per square metre, enough to reduce overall Arctic ice thickness by 80 centimetres.

The root cause is global warming, which has seen temperatures in the Arctic rise by 2 degrees from pre-industrial levels–twice the global average—leading to record-low sea ice coverage. The researchers found that with sea ice retreating, heat absorption by exposed surface waters has increased fivefold in 30 years, mainly from direct sunlight, which no longer gets reflected by ice.

 

And with no ice in the way, strong northerly winds push these newly-warmed surface waters at the Arctic fringes down to the depths where they’re now accumulating under the Arctic. The fear is that the freshwater “lid” keeping them there could fall apart.

“It could be lost through increased mechanical mixing of the water layers, especially driven by the winds,” says Mary-Louise Timmermans at Yale University and head of the team. “With continued sea-ice losses, we’d have more wind-driven mixing, and that would erode this natural barrier,” she says.

Loss of a protective “freshwater” layer is already happening elsewhere around the Arctic in the Barents Sea north of Scandinavia, allowing warmer Atlantic waters to flow in and potentially destroy an entire Arctic ecosystem in the North Barents Sea within a decade.

 

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Yeah, it takes a lot of energy to make the phase change from solid to liquid. Global mean surface temperatures are running a bit behind of most model predictions while Arctic sea ice is declining faster than originally predicted. I wonder if more of the planetary energy balance is going into the cryosphere and less in the atmosphere could explain the discrepancy? Anyway, it does appear like 2019 is shaping up to have yet another well below normal minimum extent...possibly top 3 lowest.

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We have a bit of an issue with temps being taken over big areas of the Arctic/Africa with the Arctic being the area with the potential of 'upping' the global average esp. with a record warm season like this one?

Was it Cowtan and Wray(sp?) that modelled with the Arctic/African data in and it showed us no 'pause' over the noughties and us on target for the temp rises we expected?

My 'OMG' moment will come when the summer 'Latent heat of fusion' pegged 'DMI 80N' plot suddenly lurches upward as open water begins to dominate modelled 2m temps over those controlled by melting ice? 

Every other season of the year sees DMI take some pretty big positive excursions so there is only the 'flatline ' summer that has not....... this year maybe?

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On 7/2/2019 at 9:44 AM, bdgwx said:

Yeah, it takes a lot of energy to make the phase change from solid to liquid. Global mean surface temperatures are running a bit behind of most model predictions while Arctic sea ice is declining faster than originally predicted. I wonder if more of the planetary energy balance is going into the cryosphere and less in the atmosphere could explain the discrepancy? Anyway, it does appear like 2019 is shaping up to have yet another well below normal minimum extent...possibly top 3 lowest.

It's not only the energy from the state change, it's also the reflected energy that we are losing. Open water will suck up all the sun's energy. It does't look good for any recovery that we all hoped would happen. September better hurry up and get here.

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Just now, bluewave said:

Ice has no agenda. It continues melt as the climate warms. The beauty of science is that you don’t have to believe in it for it to work.

I believe in science and I believe that the climate is warming as a result of human influence and that ice coverage will continue to go down because of it. That doesn't change that showing data for only the last 40 years only is misleading, especially as the 70's were notoriously cold. 

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31 minutes ago, Luke_Mages said:

I hate charts with an agenda.

 

8-pic1-768x392.jpg

Why does it say "using unadjusted temperature dataset"? Is the temperature displayed on it? What am I missing?

And what agenda do you think the original charts had?

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16 minutes ago, Luke_Mages said:

I believe in science and I believe that the climate is warming as a result of human influence and that ice coverage will continue to go down because of it. That doesn't change that showing data for only the last 40 years only is misleading, especially as the 70's were notoriously cold. 

The longer reconstructions further back in time make the last 40 years even more exceptional. 

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10 minutes ago, bluewave said:

The longer reconstructions further back in time make the last 40 years even more exceptional. 

These climate agenda arguments are so baffling to me, there's literally hard data from numerous sources/satellites that goes back decades to hundreds of years. 

But I guess in an age where anti-vaxxers and flat-earthers exist we shouldn't be too surprised.

Regardless, the climate will do what science intended whether you choose to remain ignorant or not. 

I kid you not there were tweets where people tried to dispute climate change by stating it snowed in Alberta last June. But mention record heat in Alaska/Europe happening now and you won't hear a peep. 

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He's not wrong that there were probably some pretty low ice extents in the late 1930s or 1940s akin to perhaps the late 1990s or early 2000s but that definitely doesn't matter in the larger picture. 

The best data starts in 1979 so that is the natural starting point for most ice related graphs. It's not some conspiracy. 

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14 hours ago, ORH_wxman said:

He's not wrong that there were probably some pretty low ice extents in the late 1930s or 1940s akin to perhaps the late 1990s or early 2000s but that definitely doesn't matter in the larger picture. 

The best data starts in 1979 so that is the natural starting point for most ice related graphs. It's not some conspiracy. 

Yeah, probably 6-7 million sq km for September extents. But nothing close to the historic drop in recent times.

https://www.carbonbrief.org/guest-post-piecing-together-arctic-sea-ice-history-1850

First, there is no point in the past 150 years where sea ice extent is as small as it has been in recent years. Second, the rate of sea ice retreat in recent years is also unprecedented in the historical record. And, third, the natural fluctuations in sea ice over multiple decades are generally smaller than the year-to-year variability.

https://mobile.twitter.com/ZLabe/status/1146506078932230144?ref_src=twsrc^google|twcamp^serp|twgr^tweet

New study in

to model #Arctic sea ice volume since 1901: "The sea ice decline over the 1979-2010 period is pan-Arctic and 6 times larger than the net decline during the 1901-40 period."

B38D5A1D-54DA-4ED6-A91F-62A791D3CE6E.thumb.png.f29c30d5fb401f51c2c880d86f2d9ec3.png

 

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2019 has stolen the lead on NSIDC area, if very narrowly. Still trails a bit on extent. Chukchi, Beaufort, ESS and CAB are taking substantial hits at the moment.

2012 drops a bit slowly over the next 5 days before diving again, so there's a chance 2019 will stay in the lead for a little while.

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10 hours ago, BillT said:

it seems as if many here WANT catastrophic warming......hoping the ice melts

I don't hope for catastrophic warming. But a record low extent makes it a more interesting season to track. I don't think there is some massive catastrophe that happens either if we break a record min. It didn't happen in 2012. We actually ended up rebounding in a big way the following season. 

Anyways, 2019 is off to a strong start in July so if we can build a couple hundred thousand lead on 2012, then we may have a chance. 2012's losses are so breathtaking later in the month and early August that we'll need to build up some more momentum. June didn't quite do the trick but if early July is hostile enough, maybe it can make up for it.  

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