Arctic Sea Ice Extent, Area, and Volume

[chubbs]

8 hours ago, bluewave said:

June officially continues the post 2012 pattern of a more active polar vortex and cooler temps.You can see the long range ensembles continuing this general pattern right into July.

 

 

 

 

July often reverses the June 500 mb tendency in the arctic with 2009+2015 being recent high height years in July and 2010+2012 relatively low.

[bluewave]

2 hours ago, chubbs said:

July often reverses the June 500 mb tendency in the arctic with 2009+2015 being recent high height years in July and 2010+2012 relatively low.

 

 After record breaking -AO and KB block last fall, the PV has mostly been in charge. While we had some transient Arctic blocking episodes, but the PV quickly makes a return.

 

 

 

 

 

 

 

 

 

[csnavywx]

After a slowdown with the PV pattern last week, the basin has lost-724k in area from the 30th-4th (on NSIDC).

[ORH_wxman]

2 hours ago, csnavywx said:

After a slowdown with the PV pattern last week, the basin has lost-724k in area from the 30th-4th (on NSIDC).

Finally melting all that snowpack on the CAB ice and getting melt ponding. The bigger question though becomes is this happening too late?

2013 saw similar losses in the same period (670k) before stalling later in the month. OTOH, years like 2008 (the closest match to 2017 for area on June 30th) decided to go nuclear a few days later (about July 5-9 losing almost 800k) and finished pretty low...albeit still around 3.00 million sq km.

[csnavywx]

On 7/5/2017 at 4:58 PM, ORH_wxman said:

Finally melting all that snowpack on the CAB ice and getting melt ponding. The bigger question though becomes is this happening too late?

2013 saw similar losses in the same period (670k) before stalling later in the month. OTOH, years like 2008 (the closest match to 2017 for area on June 30th) decided to go nuclear a few days later (about July 5-9 losing almost 800k) and finished pretty low...albeit still around 3.00 million sq km.

It's a good question. Looking at EOSDIS shows much of 2013's ponding on this date was confined to the periphery while much of the CAB snowpack survived until late July. This year shows ponding deep into the CAB -- not as extensive as 2012, but not far terribly far off either. This year is lagging behind 2012 in the Kara/Barents and Beaufort in open water coverage but ahead in the Chukchi and ESS.

The EC/EPS is backing away from a strong PV in the D5+ time period. Looks like the seasonal pattern of rapid switching will continue.

I'm really torn on how to go for minimum. Maybe a blend right down the middle with a large area of broken/partial coverage (not too dissimilar from last year). Volume not too dissimilar from 2012 (maybe slightly above) with extent well above.

[bluewave]

Interesting increase in NH snow cover for June compared to recent years. The highest in over a decade.

 

[csnavywx]

The EC op and EPS paint an interesting picture. After the current TPV starts migrating away at t+72, a big subtropical intrusion starts from the Russian side over the ESS. Temps at 700mb rise to 5+C and 500mb temps get above -10C, denoting the deep subtropical characteristics of the airmass, along with high TPW/theta-e. Most importantly with the strong WAA is the forecast wind strength and fetch, which would enable these temps to mix down effectively. The EC OP is a knockout blow from D5, but I won't speculate much past that due to the limited recent model skill.

Definitely a potential watcher for the Pacific half of the basin.

[ORH_wxman]

15 hours ago, bluewave said:

Interesting increase in NH snow cover for June compared to recent years. The highest in over a decade.

 

Greenland is actually having a historically cold summer. Kind of weird obviously in the recent warm context but it's a reminder that natural variability still plays a large role. 

[bluewave]

53 minutes ago, ORH_wxman said:

Greenland is actually having a historically cold summer. Kind of weird obviously in the recent warm context but it's a reminder that natural variability still plays a large role. 

Either natural variability or the early emergence of the CCSM4 summer pattern in response to climate change. The NH summer circulation since 2013 bears a strong similarity to the presentation below. 

https://ams.confex.com/ams/94Annual/webprogram/Paper235210.html

 

 

[WidreMann]

And yet snowcover has been very high this year. Perhaps that argues for a positive feedback cycle that might offset some of the losses expected due to warming. It'll be interesting to see how that affects the proposed changes in Siberia and in the general circulation. Either that or this year truly is an anomaly.

[csnavywx]

-377k on area from the 5th-7th, making total losses from 30 June - 7 July around -1.1M. Wouldn't be surprised to see a brief stall or slower losses for a couple of days as the cyclone in the CAB makes its way south. Upcoming pattern features a windy push of subtropical air (via omega block and a flanking cyclone) into the ESS, Chukchi and Beaufort and perhaps into part of the CAB. That should get steep losses rolling there. Potentially big push coming on the Atlantic side if the ensembles are right, which might set up some hefty losses in the D6 timeframe. I hesitate to go much further, but the GFS, GEM and EC ensembles do seem to favor a TPV position near/over the Hudson/CAA/Baffin area. With a strong subtropical ridge to the south, it's possible this configuration gets stuck in a tripole and exposes the Atlantic front to hefty losses for the first time this season. Ice thickness is precariously thin on the Eurasian side, so I wouldn't be surprised to see that fold like a cheap rug. The silver lining is that configuration would shut down export.

[The_Global_Warmer]

 

 

And there is a lot of heat already in the water 

 

With a major Ridge  about to bring more solar heating and the Southerly flow along the Pacific side. 

[Jonger]

Are we going to have a "Guess the minimum" thread/Poll?

I doubt we go below 4.25 on JAXA.

[WidreMann]

Given the state of the ice, very thin and broken up, I don't see how we don't beat 2012 by a decent margin. While the pattern isn't terrible, it's not great either. We certainly will beat it on volume.

[bluewave]

8 hours ago, WidreMann said:

Given the state of the ice, very thin and broken up, I don't see how we don't beat 2012 by a decent margin. While the pattern isn't terrible, it's not great either. We certainly will beat it on volume.

On JAXA and NSIDC extent we probably missed to our chance to beat 2012 with the stronger PV pattern from June into early July. It even fell a little behind last year in recent days. 

 

 

 

 

 

 

[ORH_wxman]

2 hours ago, bluewave said:

On JAXA and NSIDC extent we probably missed to our chance to beat 2012 with the stronger PV pattern from June into early July. It even fell a little behind last year in recent days. 

 

 

 

Yeah I'm not sure what he is seeing that indicates we will go lower than 2012...there's still an outside chance we go lower on volume only because the very thick ice near Greenland and the CAA is quite a bit thinner than 2012...but the rest of the pack is in superior shape than 2012 was at this point, so it is hard to see how the area and extent get anywhere near it. Volume will be a task...it will require probably very hostile weather from here on out. We entered July nearly tied with 2012 for volume and so far this July has been significantly colder than 2012. We had a decent chance to beat 2012 on extent/area coming into May, but the weather since then has all but eliminated that chance now...never say never, but I'd put the odds probably below 10%. Maybe if we get a 2007-esque pattern later this month and right through all of August, we will make up ground.

 

[bluewave]

20 minutes ago, ORH_wxman said:

Yeah I'm not sure what he is seeing that indicates we will go lower than 2012...there's still an outside chance we go lower on volume only because the very thick ice near Greenland and the CAA is quite a bit thinner than 2012...but the rest of the pack is in superior shape than 2012 was at this point, so it is hard to see how the area and extent get anywhere near it. Volume will be a task...it will require probably very hostile weather from here on out. We entered July nearly tied with 2012 for volume and so far this July has been significantly colder than 2012. We had a decent chance to beat 2012 on extent/area coming into May, but the weather since then has all but eliminated that chance now...never say never, but I'd put the odds probably below 10%. Maybe if we get a 2007-esque pattern later this month and right through all of August, we will make up ground.

 

Yeah, and how much colder this summer is in Greenland compared to 2012.

http://polarportal.dk/en/nyheder/arkiv/nyheder/bringing-harmonie-to-the-greenland-ice-sheet/

 

Martin Stendel, Polar Portal leader, agrees. “This year has been extremely unusual, with a snowy winter and then a cool period at the start of this month. It’s extremely important we get the surface mass balance right.”

The period from the 27^th June to the 5^th July saw days with close to zero or even slightly positive SMB (a net gain in mass) as well as a record low temperature recorded at the DMI weather station at Summit  -33.0 °C. This weather along with the snowfall in early June, and following from the heavy snow in the Autumn, has led to a relatively high surface mass balance for the time of year and an unusually bright and reflective ice sheet, as shown in the albedo anomaly map on the Polar Portal (and below). Professor Jason Box of GEUS explains “when we see cold snowy conditions like this in the summer time it brings melt to a halt. The fresh snow is bright and reflects sunlight whereas in normal years dark bare glacier ice is usually exposed at this time of year and so melt rates are strong. This is why we track the albedo through the year to see how much melt we can expect”.

So far this summer there has been less melt than usual. As DMI weather forecaster Jesper Rosberg explains, “we have seen a persistent positive North Atlantic Oscillation this summer and the jet stream has been very far south of Greenland with very cold air over the ice sheet, so the precipitation falling this summer has mostly been snow, rather rain. ” 

The cold and snowy conditions have been hindering scientific fieldwork this summer. But there are still several weeks of the ablation season left and the weather for the rest of July and August will determine the surface mass balance of Greenland this year. As far as DMI scientists know this is the first time that the SMB of the Greenland ice sheet has been calculated with such a sophisticated model in near real-time and it’s all the more interesting since we have snowfall interfering with melt. 

[The_Global_Warmer]

19 hours ago, WidreMann said:

Given the state of the ice, very thin and broken up, I don't see how we don't beat 2012 by a decent margin. While the pattern isn't terrible, it's not great either. We certainly will beat it on volume.

 

Don't know about I don't know if that'll happen but it's definitely looking like a top three bottom finish.

 

We'll just have to wait and see this pattern incoming is pretty warm all over except on the Greenland side

 

 

 

 

[The_Global_Warmer]

There is some serious melt happening well into the basin.

 

The red line is my open water estimate by seasons end. 

 

The black circle is an area of enhanced melt obscured by clouds. 

The green circle is an area of lower albedo in the Southern CAB where a buoy shows strong bottom melt.  

This is near 79N.

 

 

 

 

[ORH_wxman]

PIOMAS had a mid-month update....2017 is still lower than 2012 by a very slim margin. It is 150 km^3 lower than 2012...it was 180 km^3 lower on July 1st update so basically no change. However, the difference in the CAB has shrunk to almost zero...compared to July 1st which had quite a bit more CAB volume in 2012 versus 2017. So I think it is only a matter of time before 2012 runs away from this year...but we will see. Until the total number diverges, it is still a race.

This seems to be supported by the area numbers too (NSIDC area as measured by SSMI/S)...after starting off the month with some big drops as noted earlier in this thread....we've come to a screeching halt in area loss. We are sitting at 5.62 million sq km for area right now which is more than 800,000 sq km above 2012 at this point (with the big August cyclone still looming in 2012). We are actually ahead of 2013 and 2014 right now as well, but I do not believe we will stay there because both of those years went into big pauses later this month.

[bluewave]

17 hours ago, ORH_wxman said:

PIOMAS had a mid-month update....2017 is still lower than 2012 by a very slim margin. It is 150 km^3 lower than 2012...it was 180 km^3 lower on July 1st update so basically no change. However, the difference in the CAB has shrunk to almost zero...compared to July 1st which had quite a bit more CAB volume in 2012 versus 2017. So I think it is only a matter of time before 2012 runs away from this year...but we will see. Until the total number diverges, it is still a race.

This seems to be supported by the area numbers too (NSIDC area as measured by SSMI/S)...after starting off the month with some big drops as noted earlier in this thread....we've come to a screeching halt in area loss. We are sitting at 5.62 million sq km for area right now which is more than 800,000 sq km above 2012 at this point (with the big August cyclone still looming in 2012). We are actually ahead of 2013 and 2014 right now as well, but I do not believe we will stay there because both of those years went into big pauses later this month.

I agree. The coming cooldown across the CAB should keep 2017 behind the 2012 extent over the next  the next 10 days. 2012 will probably run away from 2017 in early August when the steep 2012 drop occurred. With the exception of July 2015, a cooler polar vortex has dominated the Arctic summers from 2013-2017.

 

 

 

 

 

[csnavywx]

2012's August losses were one of a kind ridiculous. EOSDIS doesn't show the kind of weak, broken ice pack that would be susceptible to mass extent/area loss in August like 2012 (and to some extent last year). With this turbo +AO remaining in place into the extended, there's a chance we could get get above 5M for extent in Sept if that pattern doesn't break appreciably.

[ORH_wxman]

1 hour ago, csnavywx said:

2012's August losses were one of a kind ridiculous. EOSDIS doesn't show the kind of weak, broken ice pack that would be susceptible to mass extent/area loss in August like 2012 (and to some extent last year). With this turbo +AO remaining in place into the extended, there's a chance we could get get above 5M for extent in Sept if that pattern doesn't break appreciably.

Extent has been keeping pace with the bottom years for the time being even though area has not. Seems like we've gotten a pretty compact ice pack now which has aided in the extent decline. We also lost a good amount of ice in the Greenland sea over the past few weeks as export has come to halt. I'd expect at some point we're going to see a decent stall (or slowdown to be more accurate) in extent loss once the easy pickings are gone...still some fast ice that broke off lingering int hje Laptev and Baffin Sea has some stubborn ice too that will probably contribute to losses in the next few days.

 

The late Andrew Slater's page has the extent minimum coming in around 4.6 million sq km (assuming the value on 9/9 is close to the min), so I think we'll get below 5 million sq km for the daily min. His method has been remarkably accurate for a 50 day forecast...rarely missing by more than a couple hundred thousand sq km. His method also does have a pretty big flattening out in the extent loss in late July and early August...so that supports the idea above, but path to the min isn't always as accurate.

 

The 2012 August losses are pretty easy to see the reason...it was such low concentration already by this point...the difference compared to 2017 is pretty stark:

 

 

[chubbs]

5 hours ago, csnavywx said:

2012's August losses were one of a kind ridiculous. EOSDIS doesn't show the kind of weak, broken ice pack that would be susceptible to mass extent/area loss in August like 2012 (and to some extent last year). With this turbo +AO remaining in place into the extended, there's a chance we could get get above 5M for extent in Sept if that pattern doesn't break appreciably.

Just have to avoid unusually strong storms like 2012 or prolonged storminess like 2016.

[WidreMann]

It's funny y'all are saying this, because on the Arctic sea ice forums, they seem to be convinced that we're going to have some ridiculously low year because the ice is in an unprecedented poor state. And yet the AMSR data does look considerably better than 2012, no doubt. I think the concern comes from PIOMAS being near or below 2012 and potentially overstated. We'll see. I'm moving into the camp that we won't beat 2012, but it won't exactly be pretty either.

[skierinvermont]

1 hour ago, WidreMann said:

It's funny y'all are saying this, because on the Arctic sea ice forums, they seem to be convinced that we're going to have some ridiculously low year because the ice is in an unprecedented poor state. And yet the AMSR data does look considerably better than 2012, no doubt. I think the concern comes from PIOMAS being near or below 2012 and potentially overstated. We'll see. I'm moving into the camp that we won't beat 2012, but it won't exactly be pretty either.

How long you have been following the arctic sea ice forum? I assume you mean Neven's site?

In my experience his site (and probably other similar sites) are way too pessimistic (or optimistic if you notice how giddy some of them get). 

I haven't really followed that site in a few years, but back around 2012-2014 they were off the charts with their wild predictions. 

Yeah the ice is "bad" and they do a great job showing pictures of how "bad" it is... but without a lot of aggregate empirical data or sound logic to back up predictions.

[ORH_wxman]

Yeah if you read the Arctic sea ice forums, most of them are convinced every season is going to be a record low. There's a select few posters on there that do a good job and are pretty objective about the data but you can ignore the other 90% of them. As skier said, most of them just post anecdotes...pictures of buoy webcams or zoomed-in visible satellite pics that show ice "rubble" and then claim that means it has to melt out this year. 

There's no doubt that this year started off really bad coming out of winter...likely worst on record...but it's clear now that we didn't carry that momentum into spring and summer. It will still be a pretty low ice year because of how bad we started, but I don't think we will get near any records. Maybe volume can still be close if we get some hostile weather in August. 

[bluewave]

1 hour ago, ORH_wxman said:

Yeah if you read the Arctic sea ice forums, most of them are convinced every season is going to be a record low. There's a select few posters on there that do a good job and are pretty objective about the data but you can ignore the other 90% of them. As skier said, most of them just post anecdotes...pictures of buoy webcams or zoomed-in visible satellite pics that show ice "rubble" and then claim that means it has to melt out this year. 

There's no doubt that this year started off really bad coming out of winter...likely worst on record...but it's clear now that we didn't carry that momentum into spring and summer. It will still be a pretty low ice year because of how bad we started, but I don't think we will get near any records. Maybe volume can still be close if we get some hostile weather in August. 

I think some people are coming into each season thinking that it will be a continuation of the 2007-2012 mega dipole pattern. But outside July 2015, the summer Arctic pattern did a complete reversal following that 2012 record breaking summer. It was like the 2012 extremes of low sea ice extent and Greenland melt flipped a switch over to a new regime. Maybe some type of mini summer Arctic D-O event?

 

 

 

 

 

[WidreMann]

Yes, this one: https://forum.arctic-sea-ice.net/index.php?board=3.0

I had seen csnavywx post there, so I figured there was at least some legitimacy. But there's definitely an unnecessary amount of doom and gloom.

[ORH_wxman]

3 hours ago, bluewave said:

I think some people are coming into each season thinking that it will be a continuation of the 2007-2012 mega dipole pattern. But outside July 2015, the summer Arctic pattern did a complete reversal following that 2012 record breaking summer. It was like the 2012 extremes of low sea ice extent and Greenland melt flipped a switch over to a new regime. Maybe some type of mini summer Arctic D-O event?

 

 

 

 

 

 

 

It is definitely weird that we saw an abrupt flip. I wish we knew what caused it. It seems to coincide with the formation of the deep cold pool anomaly in the North Atlantic sometime in spring of 2013 when the deep blocking from early that spring broke down. But I'm not sure what is cause and what is effect and also what is just reinforcing feedback. Probably some combo but interesting nonetheless. 

The hadgem model from Hadley center seemed to predict this on some level after 2012...which is a nice score by that model.