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Arctic Sea Ice Extent, Area, and Volume


ORH_wxman
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PDO is neutral this year and may go slightly negative, so I don't think that's going to be as big of an influence. That Atlantic SST pattern is really something else and points towards what bluewave is talking about. Although, that SST pattern is also favorable for periodic rex blocking over or just east of Greenland (towards Iceland) and an enhanced storm track south of Greenland overall (which we may incidentally see some of in the coming week). That also favors keeping troughing near the Kara/Barents area.

While this doesn't translate into a 2007/2012 or a mega-dipole type pattern it is warmer than the past few years, contingent on how the Pacific behaves. We'll have to see what kind of ponding the upcoming event on the Pacific side will generate as we're entering the critical period for that area.

https://worldview.earthdata.nasa.gov/   is a great tool for looking for the general progress of melt ponding. Last year, the CAB remained snow-covered late into the season, which limited the melt.

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  • 2 weeks later...

Strong -AD at the moment with colder temps towards the CAA/Beaufort and blowtorch conditions on the Russian half of the basin. Ponding is getting widespread over there on the latest worldview imagery showing strong melting penetrating pretty deep into the snow-covered areas of the basin.

Dprog/dt is characteristically high for this time of the year, but a strong rex block near/over the CAA appears likely to develop soon in conjunction with the Laptev block. Depending on placement, there may or may not be some penetration of strong melt conditions into the heart of the central basin in the next week. The upside is the lack of strong export and relatively cold conditions for the Beaufort and Chukchi (which need a break given the extremely weak ice front in the Chukchi atm).

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Coldest start to June over the CAB since 2014. More active June TPV pattern beginning in 2013 continues. This is in stark contrast to the extreme June dipole pattern of 2007-2012. Intense sub 970 mb Kara low this week was near record levels for early June. The  TPV that produced this  storm just split with a piece spinning toward the Beaufort.

http://ocean.dmi.dk/arctic/meant80n.uk.php

https://weathermodels.com/index.php?r=site%2Fpreview&mode=animator&set=14-km EPS Global&area=Northern Hemisphere&param=500 hPa Height Anom&offset=4

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First check on area this season....looks like we're in the middle of the pack though skewed a little more toward the lower melt years in the post-2007 environment. We're about 30k above 2017 and about 150k below 2014.

2012's freefall was already well under way...2018 is currently 500k above 2012 at this point. There's still time though....for example, 2007 was still only 25k lower than 2018 at this point, but it went nuclear over the next 10 days losing nearly 1.5 million sq km of area...an average of about 150k per day. Not sure 2018 has the weather forecast in its favor to do anything like that.

 

For anyone new in here, we usually track SSMI/S area in June because it has a much higher correlation to the minimum extent in september than June extent does. The reason is meltponding...the SSMI/S sensors get fooled by meltponding so the area concentration falls. Because of this, it is giving us a measurement of meltponding which is an excellent predictor of minimum ice extent. I'll usually make a prediction of final minimum extent and area based on the area numbers at the end of June. They have worked quite well over the years with a notable exception in 2016.

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4 minutes ago, ORH_wxman said:

First check on area this season....looks like we're in the middle of the pack though skewed a little more toward the lower melt years in the post-2007 environment. We're about 30k above 2017 and about 150k below 2014.

2012's freefall was already well under way...2018 is currently 500k above 2012 at this point. There's still time though....for example, 2007 was still only 25k lower than 2018 at this point, but it went nuclear over the next 10 days losing nearly 1.5 million sq km of area...an average of about 150k per day. Not sure 2018 has the weather forecast in its favor to do anything like that.

 

For anyone new in here, we usually track SSMI/S area in June because it has a much higher correlation to the minimum extent in september than June extent does. The reason is meltponding...the SSMI/S sensors get fooled by meltponding so the area concentration falls. Because of this, it is giving us a measurement of meltponding which is an excellent predictor of minimum ice extent. I'll usually make a prediction of final minimum extent and area based on the area numbers at the end of June. They have worked quite well over the years with a notable exception in 2016.

Doesn't the weather forecast look increasingly hostile though with a strong ridge over the Siberian side? Even if it's not a dipole, won't that degree of warmth (like +9C 850) promote melting?

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12 minutes ago, nzucker said:

Doesn't the weather forecast look increasingly hostile though with a strong ridge over the Siberian side? Even if it's not a dipole, won't that degree of warmth (like +9C 850) promote melting?

Laptev is taking a beating for sure right now...in fact it is the lowest area on record at the moment for this date in the Laptev. However, this is being offset by the East Siberian Sea and Beaufort...and to a lesser extent the CAA. The ESS has the highest area for this date since 1988...that's pretty impressive actually, and it's going to be a problem for getting massive melt. The lowest 3 on record for this date in the ESS? That would be 2007, 2012, and 2016 in that order. The ESS often has an "arm" of ice extending outward near the end of the season that can protect the central arctic basin from assault....and eroding that arm is a key to getting really low extents.

The latest forecast doesn't look impressive for that area either after about Friday or Saturday...it looks like most of the warmth stays near the shoreline in the Laptev region and Kara sea. I'm not saying this is going to go 2013 or 2014 on us at this point, just that we need to see something better than a reverse dipole to get it up into the top tier of melt years...even if that reverse dipole is warm in the Laptev and Kara. It's also acting to protect all that vulnerable ice in the Chukchi that we started the season with. There's been very little progress in eroding the Chukchi ice the past week-plus and it probably won't change much with the reverse dipole.

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46 minutes ago, ORH_wxman said:

First check on area this season....looks like we're in the middle of the pack though skewed a little more toward the lower melt years in the post-2007 environment. We're about 30k above 2017 and about 150k below 2014.

2012's freefall was already well under way...2018 is currently 500k above 2012 at this point. There's still time though....for example, 2007 was still only 25k lower than 2018 at this point, but it went nuclear over the next 10 days losing nearly 1.5 million sq km of area...an average of about 150k per day. Not sure 2018 has the weather forecast in its favor to do anything like that.

 

For anyone new in here, we usually track SSMI/S area in June because it has a much higher correlation to the minimum extent in september than June extent does. The reason is meltponding...the SSMI/S sensors get fooled by meltponding so the area concentration falls. Because of this, it is giving us a measurement of meltponding which is an excellent predictor of minimum ice extent. I'll usually make a prediction of final minimum extent and area based on the area numbers at the end of June. They have worked quite well over the years with a notable exception in 2016.

Thank you for that explanation re:  tracking area in June.

 

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Unusually cold weather near the Beaufort region for a change with the strong TPV. This is actually the coldest departures around that region over the last year. My guess is that this impressive June TPV behavior will keep the 2012 record out of reach again for this season.

tn70026_1yr.gifFrom the Alaska Weather Blog:

http://ak-wx.blogspot.com/2018/06/chilling-in-summer.html

Northern and interior Alaska has seen some very chilly weather for the time of year in the past few days, as a strong upper-level trough and an unseasonably cold air mass plunged south out of the Arctic at the beginning of the week.  Despite the fact that the summer solstice is now less than 10 days away, and daylight is continuous, sub-freezing temperatures have occurred in many of the usual cold spots in the interior.

The airport has seen 37°F, 36°F, and 37°F in the early mornings of the past three days, which is a remarkably cold series of daily minimum temperatures for this time of year.  In fact, this is the closest to the solstice that Fairbanks has ever observed 3 straight days with low temperatures of 37°F or lower at the official climate site (1930-present).

It's also interesting to note that with a high temperature of only 53°F, Monday's daily mean temperature was a mere 45°F.  It's been almost 70 years (1949) since Fairbanks saw such a chilly day this late in June (or in July).

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Nice graphs...and for those interested in AK weather & climate, that Alaska-wx blog website is great. Wow, nearly every single day from Nov 2017 - Mar 2018 was above normal in Barrow (and these are recent normals, i.e. 1981-2010)...and many of those days were way way above normal.

Perhaps it's not too surprising, as the persistently low amount of ice north of Barrow over the past 10-15 years significantly moderates the temps in Barrow due to E or NE flow...but still. 

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Models are showing a reverse dipole for the remainder of June....if that sticks, then we're prob out of any top 3 running this year. Unless we get an obscene pattern in July....2015 was able to make somewhat of a comeback in this manner.

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On June 18, 2018 at 11:31 AM, ORH_wxman said:

Models are showing a reverse dipole for the remainder of June....if that sticks, then we're prob out of any top 3 running this year. Unless we get an obscene pattern in July....2015 was able to make somewhat of a comeback in this manner.

It's been tough to bet against the reverse dipole pattern since June 2013.

 

IMG_0157.PNG.39dcf3a9f03dc4146682f22503fbddfd.PNG

IMG_0158.PNG.ce9f77c1586328f8b6d04fc86aeed306.PNG

 

 

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Update on SIA (sea ice area).....here is how other years compare to 2018 (i.e. a -542k on 2007 means that 2007 had 542,000 sq km less area than 2018 on this date)

2007: -542k

2008: +163k

2009: +721k

2010: -217k

2011: -263k

2012: -664k

2013: +124k

2014: +152k

2015: -57k

2016: -424k

2017: -13k

 

As you can see, 2017 is the closest match right now...though 2015, 2014, 2013, and 2008 weren't far off. That group of 4 right there shows how things can still change a decent amount....years like 2008 and 2015 still finished pretty low while 2014 and 2013 were the top 2 highest area minimums in the post-2007 era (2009 was the highest minimum extent though....and you can see how much area 2009 had at this point compared to those other years). We'll see how the next 10 days goes, but even by now, the contenders were already separating themselves from the pretenders.

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On June 14, 2018 at 3:08 PM, beavis1729 said:

Nice graphs...and for those interested in AK weather & climate, that Alaska-wx blog website is great. Wow, nearly every single day from Nov 2017 - Mar 2018 was above normal in Barrow (and these are recent normals, i.e. 1981-2010)...and many of those days were way way above normal.

Perhaps it's not too surprising, as the persistently low amount of ice north of Barrow over the past 10-15 years significantly moderates the temps in Barrow due to E or NE flow...but still. 

The continuing colder than average temperatures in Barrow during June are indicative of the less hostile reverse dipole pattern. It's remarkable how the extended record warmth over the last year suddenly reversed around the start of June. This is exactly what was needed to avoid challenging a record year like 2012. In September 2012, nobody would have bet that the 2012 record would still be standing near the end of the decade.

Rick Thoman

The high temperature so far this year (thru June 20 mid-afternoon) at Utqiaġvik (Barrow) is 37F (+3C). Since 1921, only 3 years have gone this late into June with a lower max temp, most recently 1955 (high temp thru June 20th 36F, +2C.

 

tn70026_1yr.gif

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55 minutes ago, AfewUniversesBelowNormal said:

This would actually be an impressive melt pattern for the arctic if it verifies

http://mp1.met.psu.edu/~fxg1/ENSHGTAVGNH_6z/ensloopmref.html

Beyond there, there is guidance for +Jul-Aug. Big melt season I think 

 

Also, today seems to be a switch from less favorable to favorable. 

Looks good for melt from about 144-240 or so....but the 11-15 day on that doesn't look impressive as it just builds the vortex back into the middle of the CAB extending over to Greenland. That's usually the opposite of what we want for big melt. Ideally we'd see a massive ridge bridge from Greenland to AK for big melt. 

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Looks like the greatest SIA loss slowdown in late June of the 2010's so far. Now close to 2014 on this date for area on the chart below. Very impressive turnaround from May when we were the lowest on record for a few days.

I am guessing the melt pond situation was toward more favorable side of recent years by the CPOM forecast.

https://www.arcus.org/sipn/sea-ice-outlook/2018/junessmi_ice_area.png

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23 hours ago, ORH_wxman said:

Looks good for melt from about 144-240 or so....but the 11-15 day on that doesn't look impressive as it just builds the vortex back into the middle of the CAB extending over to Greenland. That's usually the opposite of what we want for big melt. Ideally we'd see a massive ridge bridge from Greenland to AK for big melt. 

Surface is much warmer than upper levels right now in the Northern Hemisphere. Low at 500mb could be very warm at the surface in certain places. 

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6 hours ago, bluewave said:

Looks like the greatest SIA loss slowdown in late June of the 2010's so far. Now close to 2014 on this date for area on the chart below. Very impressive turnaround from May when we were the lowest on record for a few days.

I am guessing the melt pond situation was toward more favorable side of recent years by the CPOM forecast.

https://www.arcus.org/sipn/sea-ice-outlook/2018/junessmi_ice_area.png

Their forecast was for 5.3-5.4 million sq km September average extent. So the melt ponding must have been weak relatively speaking. 

 

The pattern does change though. Models have a pretty good dipole developing middle of next week. We will see how strong it gets and how long it lasts. 

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1 hour ago, ORH_wxman said:

Their forecast was for 5.3-5.4 million sq km September average extent. So the melt ponding must have been weak relatively speaking. 

 

The pattern does change though. Models have a pretty good dipole developing middle of next week. We will see how strong it gets and how long it lasts. 

September averages have remained in a very narrow range since 2013. It appears to be near the lowest amount of variability since 1980 for a 5 year period. 

2017....4.87

2016...4.72

2015...4.63

2014...5.28

2013...5.35

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22 minutes ago, AfewUniversesBelowNormal said:

There is near record Hadley Cell expansion coming up in a pattern change in 6-7 days. Would favor arctic melt down the line I think. 

The pattern next week definitely looks more favorable to melt, but hard to say how long it lasts. Euro ensembles put the vortex back over the CAB in the 11-15 range...but it could be wrong. Sometimes the patterns lock in longer than models initially show. 

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Afaik, the Arctic melt is largely driven from below, by warmer ocean water.

It would be very useful to have some actual water temperature data characterizing the various currents that impact the Arctic Ocean.

Obviously the data is really hard to get, but surely someone has worked this problem.

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19 hours ago, ORH_wxman said:

The pattern next week definitely looks more favorable to melt, but hard to say how long it lasts. Euro ensembles put the vortex back over the CAB in the 11-15 range...but it could be wrong. Sometimes the patterns lock in longer than models initially show. 

More favorable for melt, but nothing too extreme looking.The dipole ridge won't be anywhere near as strong as the ridge that was located over Siberia this month. Check out the record heat under that ridge.

31°C (89°F) is mighty impressive at 73N latitude along the Arctic Ocean.twitter.com/EKMeteo/status…
 

IMG_0162.GIF.ef87e3ae521c0b948bdb73059b4b46f1.GIF

 

 

 

 

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5 hours ago, bluewave said:

More favorable for melt, but nothing too extreme looking.The dipole ridge won't be anywhere near as strong as the ridge that was located over Siberia this month. Check out the record heat under that ridge.

31°C (89°F) is mighty impressive at 73N latitude along the Arctic Ocean.twitter.com/EKMeteo/status…
 

 

 

 

Yeah I'd agree with that. It's not a real death ridge like we had at times during 2007, 2010, 2011, and 2012....or even July 2015. 

But it should accelerate the melt ponding more. The area loss has been really weak the last few days. We're falling way behind the big dog years now. I'm on my phone now, but probably tomorrow when back on my PC I will do another rundown on the numbers. I think we're around a million sq km behind a year like 2012 now. 

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7 minutes ago, ORH_wxman said:

Yeah I'd agree with that. It's not a real death ridge like we had at times during 2007, 2010, 2011, and 2012....or even July 2015. 

But it should accelerate the melt ponding more. The area loss has been really weak the last few days. We're falling way behind the big dog years now. I'm on my phone now, but probably tomorrow when back on my PC I will do another rundown on the numbers. I think we're around a million sq km behind a year like 2012 now. 

It's remarkable how the Oct-May strong blocking ridge pattern over the Arctic finds a way to shift in June. This has been a very reliable reversal over the last 6 years. Notice how the strong Oct-May Arctic blocking pulls back to Siberia/Bering just in time for summer. This seasonal circulation change seems to be the only thing keeping the 2012 record out of reach for the time being. 

IMG_0163.PNG.5b8d854a7a0a4140566e584629d8a669.PNG

IMG_0164.PNG.00508ff7f66d7c078fd424137da20d23.PNG

 

 

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Perhaps the heat flux is forcing the PV to be more compact in addition to some natural summer variability in the Atlantic domain. Global warming saves the ice? Could be at least for the time being until some bigger players enter the field. Those factors would include melting of ice from below and rain on ice/humid arctic.

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We love our bbr2314 (Quoted from ASIF)

bbr2314

« Reply #1603 on: Today at 07:49:13 PM »
 
The situation has actually been quite similar to 2012 this June, IMO. The differences are that we are more "advanced" in accumulating oceanic heat so the Hadley Cells have advanced farther north, while the albedo impacts have also created new negative anomalies as ^ has occurred prior to full continental melt-out.

You can clearly see that heat has been pouring into the Arctic just as it did in 2012, only this year, due to what has happened re: Kara, it has been forced even farther N, entering over the Laptev. The anomalies have been scorching over half of the Arctic.

While the rest of the CAB has been about normal, that is irrelevant to what is going to happen next. If you roll 2012's monthly anomalies forward, the areas that accumulated the most heat early on in the season featured the brightest reds come September and October.

If we can imagine the same happening this year (and I don't see why we shouldn't at this point), we can magnify the June pattern into July, August, and September. This results in a near-perfect "sequential" melt out of the weakest ice in terms of accumulating albedo feedbacks into autumn, so the "order of operations" for reaching the CAB and melting it out by late July or August is much more efficient this year than in any year prior, IMO.

Oh, and the PAC is far worse than 2012, as is the high ATL, in terms of SSTs / available & impending heat through autumn.
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