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Arctic Sea Ice Extent, Area, and Volume


ORH_wxman
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The AMOC is slow enough to stop further catastrophic melting of the Greenland Ice Sheet but fast enough to cause extreme heat events in Europe (and the US?). That can't be a good thing. As well we know Antarctica holds 5x the fresh water content of Greenland.

Maybe it's just a natural variability and revision to the mean but I would say it's not a good sign. We still have tremendous heat transport in the Atlantic. This can't hold for much longer without causing massive damage to something/somebody. If you thought Sandy and Harvey was bad just wait a few years.

color_newdisp_anomaly_100W_35W_15N_65N_o

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Things have trended pretty strongly away from +AO today. Warmer at the surface trend looks to continue, perhaps significantly. I think there will be a lot of +500mb heights in the Arctic circle for July. Also, Pacific-squeezed north Hadley Cell sustainable rarely works in verification.. more blocking over the Pole. 

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12 hours ago, StormchaserChuck! said:

Things have trended pretty strongly away from +AO today. Warmer at the surface trend looks to continue, perhaps significantly. I think there will be a lot of +500mb heights in the Arctic circle for July. Also, Pacific-squeezed north Hadley Cell sustainable rarely works in verification.. more blocking over the Pole. 

Chuck, the lower NAO in some of the forecasts is a result of more east based blocking closer to Europe. Pattern back closer to the CAB and Beaurfort is actually one of the strongest July reverse dipole patterns we have seen. Notice the best ridging is focused over Siberia. The models actually have near record low 500 mb heights near the Beaufort for this time of year. 

 

IMG_0172.thumb.PNG.1d2e6cb2be14c88f6d389c7f10116ee5.PNG

 

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Yeah this is about as massive as a vortex as you'll see in the arctic during the summer. The only variable factor working strongly against the ice over the next 2 weeks is the furnace the ESS sees over the next 2 days before the vortex takes over.

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Probably one of the the best June outcomes the Chukchi can expect in a post 2007 sea ice era.

Chukchi Sea ice extent (from @NSIDC passive microwave data) decreased by 13% during June. The good news: this is the lowest percent decline in June since 2008. The bad news: trend is for more June melt: this would have typical in the 1980s. #Arctic #akwx @Climatologist49 @ZLabepic.twitter.com/KzgcbGy5Tb
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Also of interest -- the CANSIPS, which showed a slow melt season (via MSLP anomalies) many months ago is showing the same pattern next season already -- with a strong -AO pattern in spring transitioning into another strong +AO summer. It has cold SPG/NATL temps staying in place as it did this year.

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3 hours ago, csnavywx said:

Also of interest -- the CANSIPS, which showed a slow melt season (via MSLP anomalies) many months ago is showing the same pattern next season already -- with a strong -AO pattern in spring transitioning into another strong +AO summer. It has cold SPG/NATL temps staying in place as it did this year.

We've been speculating on here for some time...but I can't help but think the big change in SSTA pattern in the North Atlantic south of Greenland starting in late spring of 2013 is definitely linked to the different summers we've been seeing since then. Seems like too much of a coincidence...I'm not sure how much is chicken/egg....but we do know that feedback loops will develop with persistent SSTA patterns...so if there's isnt' a very large atmospheric force to overcome the status quo, then we keep seeing a reversion back to the +NAO/+AO type pattern. I thought this year might be a little different because we saw some impressive blocking up there in March and then into spring time we saw more bouts of good blocking. We hadn't seen any sustained blocking in the cold season like we saw in March since winter of '12-'13....so it was definitely a change. But it flipped a switch again once we got near June.

 

But that negative SSTA in the N ATL has been pretty persistent for 5 years now...maybe some brief interludes in 2016 I recall and late last summer. I remember back during the big dipole years of 2010-2012, it was bright red up in that region.

 

 

cdas-sflux_ssta_global_1.png

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3 hours ago, ORH_wxman said:

We've been speculating on here for some time...but I can't help but think the big change in SSTA pattern in the North Atlantic south of Greenland starting in late spring of 2013 is definitely linked to the different summers we've been seeing since then. Seems like too much of a coincidence...I'm not sure how much is chicken/egg....but we do know that feedback loops will develop with persistent SSTA patterns...so if there's isnt' a very large atmospheric force to overcome the status quo, then we keep seeing a reversion back to the +NAO/+AO type pattern. I thought this year might be a little different because we saw some impressive blocking up there in March and then into spring time we saw more bouts of good blocking. We hadn't seen any sustained blocking in the cold season like we saw in March since winter of '12-'13....so it was definitely a change. But it flipped a switch again once we got near June.

 

But that negative SSTA in the N ATL has been pretty persistent for 5 years now...maybe some brief interludes in 2016 I recall and late last summer. I remember back during the big dipole years of 2010-2012, it was bright red up in that region.

 

 

cdas-sflux_ssta_global_1.png

After digging further, it looks like 2013's SST pattern had more in common with 2009 (i.e. cooler interludes in an otherwise warm phase). The real shift appears to have taken place over the following winter:

https://link.springer.com/article/10.1007%2Fs00382-015-2819-3

http://iopscience.iop.org/article/10.1088/1748-9326/11/7/074004

Leads to this paper (both previous papers cited in this one):

https://www.nature.com/articles/s41598-017-11046-x

 

The particularly interesting part of that last paper (from 2017) is how deep the strong OHC anomalies extend (down past 1000m). As the paper mentions, it's going to take a lot to erase that:

Quote

The forecast suggests that the cold anomaly will likely persist over the next 2 years with a probability of 0.8. The persistence of subpolar OHC anomalies, and the dominance of subpolar OHC anomalies on the AMO (Fig. 

4a) is consistent with the expectation that OHC, rather than SST, carries the memory of the ocean. In the subpolar region, we further expect that subpolar anomalies are generated by irreversible (diabatic) processes and that once formed, take several years for the anomaly to advect or mix away.

 

 

 

 

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A -500 meter anomaly vortex is about as strong as I can ever remember seeing in July. This pattern produced the heaviest July snow in Barrow since 1963.

 

DhlDh7RVQAAsLH7.jpg-small.jpg.488c2a9cf69f5325220e99cf39309e9f.jpg

 

The NWS in Utqiaġvik (Barrow) reported 2.0" of snow on Saturday, making this the greatest July calendar day snowfall there since July 4, 1963, when there was 2.9" of snow. #akwx @Climatologist49 @CinderBDT907pic.twitter.com/lkmlmCAG8N

 

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That means that snow is likely accumulating on the ice pack too...that's going to slow down melt further. 

The rest of Hudson Bay is finally going and same with Baffin and Kara so the extent loss should be decent over the next week...but I'd expect area loss to slow....we had seen a big jolt in area loss with that brief but intense torch at the end of last week. 

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2 hours ago, Weatherdude88 said:

NSIDC northern hemisphere sea ice extent is now 12th place for 7.9.2018 with a daily value of 9.217 millions of square kilometers. July 9th, of 1995 had a daily value of 9.655 millions of square kilometers. It is possible, given the modeled favorable arctic sea ice retention conditions, we will have a greater sea ice extent value than 1995 within 2 weeks.

ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/seaice_analysis/   

I think we will speed up extent loss quickly....because look at Hudson Bay, Kara, and Baffin Bay....they have high extent for this time of the year, but they (esp Kara and Hudson) are very low concentration. So it will all go "poof" pretty soon and you'll see some big extent losses because of that. That said, for the main ice pack in the arctic basin, the weather will remain quite favorable for ice retention, so after Hudson/Baffin/Kara melt out, we will probably see another slowdown.

 

 

2018_AMSR2_July9th.png

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The June AMO came in at the lowest value since 2002.

https://www.esrl.noaa.gov/psd/data/correlation/amon.us.long.data

AMO peak looks like it was 2005-2012, after warming a lot in 1997-2004 and near neutral for much of 1989-1996. We may be transitioning to a more Neutral AMO for 2019-2026 before the real flip to the cold phase begins. I look at 2013-2018/9 as kind of a "warm, but cooling" era.

We seem to be past the era when every month is warm in the Atlantic, to where MOST months are warm, and soon it will be half, then it will be rare, and so on.

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11 hours ago, bluewave said:

Just beginning to see the area loss rate slow. Looks very close to 2013 as of the most recent update. The CPOM September average extent forecast based on melt ponding was near 2013. The longer this reverse dipole persists, the more confidence there will be for a NSIDC September average extent at or a little above 5 million sq km.

ssmi_ice_area.png

The flip side to this is the fact that the record +AO still isn't enough to get a recovery to pre-2007 levels -- only enough to mostly cover for the higher winter temps. You may be right that when we look back, 2007 may have been the most important point in the entire sequence. I'm sure we'll get to some point where extent drops out rapidly towards zero in late Aug in the future, but the biggest change was probably the Beaufort gyre turning from a nursery for ice to a MYI graveyard. That change looks irreversible at this point.

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Bluewave,

 

You posted this paper earlier and the post is gone:

https://www.nature.com/articles/ncomms14375

I meant to comment on it earlier but ran out of time that day.

 

It's definitely an interesting and concerning paper. I've read it a couple of times before. I'm not sure that's what's going on here, as it seems that most of the cooling was from diabatic heat loss, but the mechanisms mentioned in the paper are definitely a concern down the road. It looks like most of the ones that predict deep ocean convection collapse in the SPG target right around mid-century. The SPG collapse happens almost regardless of emissions path too (happens in 2.6 and 8.5). The fact that only the higher skill models do it and it happens regardless of emissions scenario does set off an alarm bell that they might be on to something. The authors obviously thought so as well.

It's interesting that the earlier paper you linked (from 2012) showed some SPG instability that the authors dismissed as a 'freak occurrence'. Perhaps not?

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11 hours ago, csnavywx said:

The flip side to this is the fact that the record +AO still isn't enough to get a recovery to pre-2007 levels -- only enough to mostly cover for the higher winter temps. You may be right that when we look back, 2007 may have been the most important point in the entire sequence. I'm sure we'll get to some point where extent drops out rapidly towards zero in late Aug in the future, but the biggest change was probably the Beaufort gyre turning from a nursery for ice to a MYI graveyard. That change looks irreversible at this point.

Yeah, 2007 to 2012 was a truly historic period for the Arctic. Some people may not appreciate the rarity of locking in that dipole patttern for 6 seasons in a row. 

https://onlinelibrary.wiley.com/doi/pdf/10.1029/2012GL053268

Thus we can say that a six year run of near one standard deviation negative excursions (2007–2012) is unique in the 63 year record. To further test the significance of the 2007–2012 AD patterns we randomly generated 10,000 time series, each with 63 points to match the observed time series and with a normal distribution without autocorrelation. For this simple calculation, the chance for having five consecutive values with a negative AD of magnitude greater than 1.0 standard deviation units in a sample size of 63 is rare, less than 1 in a 1000.

 

 

11 hours ago, csnavywx said:

Bluewave,

 

You posted this paper earlier and the post is gone:

https://www.nature.com/articles/ncomms14375

I meant to comment on it earlier but ran out of time that day.

 

It's definitely an interesting and concerning paper. I've read it a couple of times before. I'm not sure that's what's going on here, as it seems that most of the cooling was from diabatic heat loss, but the mechanisms mentioned in the paper are definitely a concern down the road. It looks like most of the ones that predict deep ocean convection collapse in the SPG target right around mid-century. The SPG collapse happens almost regardless of emissions path too (happens in 2.6 and 8.5). The fact that only the higher skill models do it and it happens regardless of emissions scenario does set off an alarm bell that they might be on to something. The authors obviously thought so as well.

It's interesting that the earlier paper you linked (from 2012) showed some SPG instability that the authors dismissed as a 'freak occurrence'. Perhaps not?

Yeah, it seems like the SPG region cooling south of Greenland since 2012 is the result of an atmospheric circulation change to more low pressure. SST’s in that region we’re near record levels of warmth prior to the abrupt circulation shift leading into the 2013 summer. Maybe there is some mechanism by which salinity changes following the 2007-2012 record melt can lead atmospheric circulation shifts by months or years?

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1 hour ago, JWilliam9830 said:

Dh8D37cUwAYhWFm.jpg

Data from the danish meteorological institute.

http://www.dmi.dk/en/groenland/maalinger/greenland-ice-sheet-surface-mass-budget/

There seems to be a lot more ice than 2011-12. This is during the height of melt season and we are well above the 1981-2010 mean.

Think this data represents the mass balance for the single year only, so we may have an increment to the total ice mass, rather than a wash.

The total Greenland ice cap is estimated at about 2.8 million cubic kilometers, or 2.8 million billion tons of ice, so adding or subtracting a few hundred billion tons does not change the overall picture.

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SMB doesn't account for calving and discharge at the periphery, which is significant. Despite the cooler conditions, this surface melt season is still above the 1981-2010 average and with the oncoming melt in the next week or two, it will probably remain so for this season. The 2012 melt season was exceptional and doesn't (yet) represent the norm. When we get to the point where SMB can't crack positive (as it almost did that year), it'll represent the non-viability of the ice sheet in the long term and a permanent shift to widespread net ablation. I suspect that will happen consistently when we lose sea ice in the late summer.

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11 hours ago, JWilliam9830 said:

 

Data from the danish meteorological institute.

http://www.dmi.dk/en/groenland/maalinger/greenland-ice-sheet-surface-mass-budget/

There seems to be a lot more ice than 2011-12. This is during the height of melt season and we are well above the 1981-2010 mean.

Lowest surface loss in decades for June. The record late snowpack prevented the local shorebirds from nesting this season.

after months of a persistent atmospheric circulation pattern, Greenland is having its least surface ice loss in decades while NW Europe has extreme sun and heat... persistent extremes are an expected signature of #climatechange@PolarPortal #ukheatwave twitter.com/severeweatherE…pic.twitter.com/lsXraH5nuK
 
But Churchill Falls (Labrador) saw its coldest June by a 2C margin; the monthly temperature was 6C below normal. Persistent major circulation anomalies are to blame. pic.twitter.com/Iz5QPeXuBr
 
 
Millions of shorebirds descend on the Arctic each year to mate and raise chicks during the tundra’s brief burst of summer. But that burst, which usually begins in mid-June, never arrived this year for eastern Greenland’s shorebirds, a set of ground-nesting species. Instead, a record late snowpack—lingering into July—sealed the birds off from food and nesting sites. Without these key resources avian migrants to the region will not reproduce in 2018, experts say.
 
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On 7/12/2018 at 10:35 PM, csnavywx said:

SMB doesn't account for calving and discharge at the periphery, which is significant. Despite the cooler conditions, this surface melt season is still above the 1981-2010 average and with the oncoming melt in the next week or two, it will probably remain so for this season. The 2012 melt season was exceptional and doesn't (yet) represent the norm. When we get to the point where SMB can't crack positive (as it almost did that year), it'll represent the non-viability of the ice sheet in the long term and a permanent shift to widespread net ablation. I suspect that will happen consistently when we lose sea ice in the late summer.

Care to post some graphs which account for calving and discharge? No matter how you slice it it’s clear that this season’s SMB is well above average and is close to breaking levels we haven’t seen in the past 30 years.

accumulatedsmb.png

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Well this  is Interesting...

 

Moreover, Arctic mid-summer temperatures, north of 80°N latitude, have dipped to near freezing over the past days. This is likely in large part linked to the cold North Atlantic sea surface temperatures we’ve been witnessing. All this suggests ocean cycles, and not CO2, are the real Arctic drivers.

Snow and ice climbing past decade

The cold polar temperatures are naturally having an impact on Arctic snow and ice.

Japanese blogger Kirye tweeted here that Arctic sea ice volume is currently at the 4th highest level since 2003, thus defying the dire alarmist predictions of Arctic sea ice disappearing by now.

-------------------------

40-year veteran meteorologist Joe Bastardi at WeatherBell’s Saturday Summary shows how the Earth’s surface has cooled dramatically over the past three years and that Arctic sea ice is piling up.

http://notrickszone.com/2018/07/15/global-sea-sea-surface-temperatures-have-seen-pretty-dramatic-turnaround-says-40-year-meteorologist/

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6 hours ago, snowlover91 said:

Care to post some graphs which account for calving and discharge? No matter how you slice it it’s clear that this season’s SMB is well above average and is close to breaking levels we haven’t seen in the past 30 years.

Here is a chart from DMI which shows total mass change for Greenland by region reflecting both SMB and glacier discharge and iceberg calving. Biggest mass losses have been on the west coast which doesn't get as much precipitation as the east coast. Greenland SMB is up this year due to heavy precipitation, unusual compared to some recent big melt years, but not unexpected given natural variability.

 

greenlandmassbasin.png

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36 minutes ago, chubbs said:

Here is a chart from DMI which shows total mass change for Greenland by region reflecting both SMB and glacier discharge and iceberg calving. Biggest mass losses have been on the west coast which doesn't get as much precipitation as the east coast. Greenland SMB is up this year due to heavy precipitation, unusual compared to some recent big melt years, but not unexpected given natural variability.

 

greenlandmassbasin.png

Does that graph go into 2018? Do you have links to these sources? Would be interested in checking them out further. 

 

I think its obvious that globally there are some changes going on in regards to the ice levels. The Arctic, Antarctic and SMB of Greenland have all showed much higher levels compared with previous years. In fact Antarctica is almost smack dab on the 1981-2010 median and the Arctic is a good bit higher than most recent years except 2014. It remains to be seen if this is just a blip or not. 

 

307A5FAB-ABCF-41FB-ABD9-8462EF32C286.png

209A37BE-3908-4D60-B833-FDE7747EDD14.png

AFB4858F-7192-4498-A594-32122F478E81.png

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The Greenland stuff is interesting but the MB has a high error bar because they use GRACE data and there's a lot of debate on what the isostatic adjustments should be. There's some big back and forth in the literature right now about these...mostly centered on Antarctica but it does pertain to Greenland too. We know Greenland has been losing mass the past decade-plus but we just aren't quite sure on the magnitude. 

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6 hours ago, snowlover91 said:

Does that graph go into 2018? Do you have links to these sources? Would be interested in checking them out further. 

 

I think its obvious that globally there are some changes going on in regards to the ice levels. The Arctic, Antarctic and SMB of Greenland have all showed much higher levels compared with previous years. In fact Antarctica is almost smack dab on the 1981-2010 median and the Arctic is a good bit higher than most recent years except 2014. It remains to be seen if this is just a blip or not.

 

A couple of comments:

1) One year in the arctic or antarctic is not very important.

2) GRACE data in graph is through 2017. See post above for papers on Greenland mass balance.

3) Regarding arctic sea ice, this year so far looks unremarkable to me. Its not a big melt year like 2012, but its not far from the long-term trendline on most metrics either. (see chart below)

4) There hasn't been any long-term trend in Antarctic sea ice so smack dab on the median is as expected. Ice shelves and ice sheets are the big concern in Antarctica, not sea ice.

BPIOMASIceVolumeAnomalyCurrentV2.1.png

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