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Arctic Sea Ice Extent, Area, and Volume


ORH_wxman
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The heat is not yet showing up, at least in the DMI  (Danish Meteorological Institute) Arctic temperature tracking:

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

So where is it?

Separately, with all this accumulated oceanic heat, can we forecast a new low for September Arctic ice?  What if anything could gum up the process?

It is important to couple the measurements to real forecasts, else the utility of the measurements becomes arguable.

 

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1 hour ago, etudiant said:

The heat is not yet showing up, at least in the DMI  (Danish Meteorological Institute) Arctic temperature tracking:

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

So where is it?

Separately, with all this accumulated oceanic heat, can we forecast a new low for September Arctic ice?  What if anything could gum up the process?

It is important to couple the measurements to real forecasts, else the utility of the measurements becomes arguable.

 

The heat is put simply building outside of the CAB and the CAB is mostly centered around 80N. You would really be hard-pressed to have a completely ice-free Arctic. It's more significant to have an ice-free Bering Sea all year around for example. Perhaps as a Canary in the coal mine for the Arctic as a whole.

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Thanks, I see where you are coming from, the northern oceans are warmer than in 2012 and the pattern of heat anomalies over Russia is similar.

Against that, the Greenland to Alaska side of the Arctic is below normal, rather than above. That suggests the direction of the flows will matter. 

Is there an expectation that the flow direction will be Russia to Canada? 

I do remember seeing masses of driftwood deposited on the northern shores of Iceland, which the guide told us had come across the Arctic from Russia, so that may be the rule.

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5 hours ago, Vice-Regent said:

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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index.php?action=dlattach;topic=2278.0;a

I think that is Nikolai on that forum...who used to post on here. There's no empirical evidence whatsoever that the ice is in worse shape than 2012 was at this point. 

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2 hours ago, AfewUniversesBelowNormal said:

Global pattern change coming in 6-7 days per models, I think it will accelerate ice melt to near record levels through July

(I can already feel it)

LoL

You're going to be disappointed.

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Here's other years compared to 2018 now:

2007: -886k

2008: -77k

2009: +554k

2010: -599k

2011: -358k

2012: -908k

2013: +3k

2014: -125k

2015: -213k

2016: -666k

2017: -242k

 

Only 2013 and 2009 have higher area than 2018 now in the post-2007 world, and 2013 is basically a dead heat...only 3k difference. I'm surprised 2014 has fallen lower than this year...though 2014 does finish the month slow. The forecast definitely calls for worsening weather for the ice in a few days, so we may pick up a little steam before June ends....finishing the month with less area than 2014 wouldn't be surprising given those two pieces of information.

 

That said, we will need to see something pretty special to achieve a top 3 or even top 5 melt season.

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Looks like the HadGEM1 is doing a great job so far. Very impressive considering the paper was first published back in 2012. 

https://www.the-cryosphere.net/7/555/2013/tc-7-555-2013.pdf

Mechanisms causing reduced Arctic sea ice loss in a coupled climate model

Abstract. The fully coupled climate model HadGEM1 pro- duces one of the most accurate simulations of the historical record of Arctic sea ice seen in the IPCC AR4 multi-model ensemble. In this study, we examine projections of sea ice de- cline out to 2030, produced by two ensembles of HadGEM1 with natural and anthropogenic forcings included. These en- sembles project a significant slowing of the rate of ice loss to occur after 2010, with some integrations even simulating a small increase in ice area. We use an energy budget of the Arctic to examine the causes of this slowdown. A negative feedback effect by which rapid reductions in ice thickness north of Greenland reduce ice export is found to play a major role. A slight reduction in ocean-to-ice heat flux in the rele- vant period, caused by changes in the meridional overturning circulation (MOC) and subpolar gyre in some integrations, as well as freshening of the mixed layer driven by causes other than ice melt, is also found to play a part. Finally, we assess the likelihood of a slowdown occurring in the real world due to these causes.

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1 hour ago, bluewave said:

Looks like the HadGEM1 is doing a great job so far. Very impressive considering the paper was first published back in 2012. 

https://www.the-cryosphere.net/7/555/2013/tc-7-555-2013.pdf

Mechanisms causing reduced Arctic sea ice loss in a coupled climate model

Abstract. The fully coupled climate model HadGEM1 pro- duces one of the most accurate simulations of the historical record of Arctic sea ice seen in the IPCC AR4 multi-model ensemble. In this study, we examine projections of sea ice de- cline out to 2030, produced by two ensembles of HadGEM1 with natural and anthropogenic forcings included. These en- sembles project a significant slowing of the rate of ice loss to occur after 2010, with some integrations even simulating a small increase in ice area. We use an energy budget of the Arctic to examine the causes of this slowdown. A negative feedback effect by which rapid reductions in ice thickness north of Greenland reduce ice export is found to play a major role. A slight reduction in ocean-to-ice heat flux in the rele- vant period, caused by changes in the meridional overturning circulation (MOC) and subpolar gyre in some integrations, as well as freshening of the mixed layer driven by causes other than ice melt, is also found to play a part. Finally, we assess the likelihood of a slowdown occurring in the real world due to these causes.

The model would suggest pretty flat trends in extent minimums out to the late 2020s before resuming a faster downward trend.

 

It is definitely fairly impressive it predicted the current stall....we will just have to see if it is accurate in how long it lasts. It would suggest another decade of mostly the same.

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Paltry area melt continues for the time being in 2018....updated numbers:

2007: -988k

2008: -162k

2009: +439k

2010: -776k

2011: -401k

2012: -995k

2013: -29k

2014: -207k

2015: -268k

2016: -749k

2017: -363k

 

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6 hours ago, ORH_wxman said:

The model would suggest pretty flat trends in extent minimums out to the late 2020s before resuming a faster downward trend.

 

It is definitely fairly impressive it predicted the current stall....we will just have to see if it is accurate in how long it lasts. It would suggest another decade of mostly the same.

It's as if the historic summer Greenland melt in 2012 really slowed the AMOC. Shortly after that, the cold pool and strong vortex couplet became a persistent feature south of Greenland. The colder waters there seem to go along with more low pressure over the Arctic during the summer. It's pretty much the opposite of the warmer SST's and the summer Arctic mega-dipole  from 2007-2012. It will be interesting to see how long this pattern persists.

https://www.carbonbrief.org/atlantic-conveyor-belt-has-slowed-15-per-cent-since-mid-twentieth-century

https://www.climate.gov/news-features/understanding-climate/summer-2012-brought-record-breaking-melt-greenland

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8 hours ago, bluewave said:

It's as if the historic summer Greenland melt in 2012 really slowed the AMOC. Shortly after that, the cold pool and strong vortex couplet became a persistent feature south of Greenland. The colder waters there seem to go along with more low pressure over the Arctic during the summer. It's pretty much the opposite of the warmer SST's and the summer Arctic mega-dipole  from 2007-2012. It will be interesting to see how long this pattern persists.

https://www.carbonbrief.org/atlantic-conveyor-belt-has-slowed-15-per-cent-since-mid-twentieth-century

https://www.climate.gov/news-features/understanding-climate/summer-2012-brought-record-breaking-melt-greenland

We've made the comment before...but that North Atlantic cold pool really started becoming noticeable in spring 2013 and that was also the last time we saw sustained NAO blocking in the cold season. We've since seen shorter intervals occasionally (like Jan 2016 before the mid-Atlantic blizzard and this past March perhaps may have been the most impressive since 2013) but it's been hard to come by what we saw multiple times during winters between 2009-2013. 

Ive wondered if these were all related. I tend to lean in the direction of yes. 

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11 hours ago, ORH_wxman said:

Paltry area melt continues for the time being in 2018....updated numbers:

2007: -988k

2008: -162k

2009: +439k

2010: -776k

2011: -401k

2012: -995k

2013: -29k

2014: -207k

2015: -268k

2016: -749k

2017: -363k

 

I'm not sure of this data.. NASA I think shows something different. 

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17 minutes ago, AfewUniversesBelowNormal said:

I'm not sure of this data.. NASA I think shows something different. 

The data is from NSIDC...it is sea ice area (not extent). Area from NSIDC (or anyone who uses SSMI/S) is a better predictor of final minimum extent at this point than extent itself is...and that is because the SSMI/S sensors are sensitive to melt ponding....and melt ponding in June is very crucial to the final minimum. So using the area data from that source is sort of like de facto real-time melt pond data. 

The ice sheet has gotten off to a very slow start with melt ponds which will make it difficult to reach extremely low extent and area in September....even if the weather turns more hostile. It is still probably theoretically possible to get a bottom 3 year, but we will have to see a very special pattern sustain itself for weeks to make up for the slow start. 

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3 hours ago, ORH_wxman said:

We will be without NSIDC data for a few days. Planned maintenance from 6/25-6/29. 

This is a critical time for tracking ice levels. What are they changing/replacing/adjusting? If the data comes in grossly different after the so-called "maintenance", there will be a lot of skeptical folks out there.

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2 hours ago, Weatherdude88 said:

The NSIDC northern hemisphere arctic sea ice extent value for 6.25.2018 is 10.241 millions of square kilometers. This places 2018 northern hemisphere sea ice exent in 7th place for the date. I predict we will continue to slowly catch up to area, given how compact the northern hemisphere cryosphere is this year. 

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

Yeah looks like we snuck in one more day of data....here's updated area numbers. The gap continues to widen as 2018 has basically stopped losing area for the past several days.

 

2007: -1.03 million sq km

2008: -228k

2009: +352k

2010: -915k

2011: -429k

2012: -1.05 million

2013: -77k

2014: -245k

2015: -295k

2016: -817k

2017: -483k

 

 

Given how little melt 2018 has had recently and the fact it has a lot of area still in Hudson bay, I decided to filter out the peripheral seas. Even when I do that, 2018, is basically neck and neck with 2013 and 2014. It is 10k ahead of 2013 and a lowly 300 sq km ahead of 2014 when i eliminate Hudson, Baffin, Greenland, Othotsk, St. Lawrence, etc....and it is much further ahead of 2015 than above when I use that filter. 2015 still had a lot of ice in those peripheral seas too which was masking the central area deficiency a bit.

 

It is hard to imagine a top 5 being really possible given that data...but I suppose we cannot completely rule it out if some crazy weather pattern locked in.

 

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1 hour ago, ORH_wxman said:

Yeah looks like we snuck in one more day of data....here's updated area numbers. The gap continues to widen as 2018 has basically stopped losing area for the past several days.

 

2007: -1.03 million sq km

2008: -228k

2009: +352k

2010: -915k

2011: -429k

2012: -1.05 million

2013: -77k

2014: -245k

2015: -295k

2016: -817k

2017: -483k

 

 

Given how little melt 2018 has had recently and the fact it has a lot of area still in Hudson bay, I decided to filter out the peripheral seas. Even when I do that, 2018, is basically neck and neck with 2013 and 2014. It is 10k ahead of 2013 and a lowly 300 sq km ahead of 2014 when i eliminate Hudson, Baffin, Greenland, Othotsk, St. Lawrence, etc....and it is much further ahead of 2015 than above when I use that filter. 2015 still had a lot of ice in those peripheral seas too which was masking the central area deficiency a bit.

 

It is hard to imagine a top 5 being really possible given that data...but I suppose we cannot completely rule it out if some crazy weather pattern locked in.

 

Yeah, CPOM may be close if July and August continue with more low pressure over the Arctic like June.

First set of forecasts for the September Arctic sea-ice extent have been collated. Median forecast (4.6M sqkm) is slightly lower than last year’s observed value. The @CPOM_news forecast from @UniRdg_Met is one of the larger forecasts at 5.3M sqkm. arcus.org/sipn/sea-ice-o…pic.twitter.com/kgaROTK7Yr
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11 minutes ago, bluewave said:

Yeah, CPOM may be close if July and August continue with more low pressure over the Arctic like June.

First set of forecasts for the September Arctic sea-ice extent have been collated. Median forecast (4.6M sqkm) is slightly lower than last year’s observed value. The @CPOM_news forecast from @UniRdg_Met is one of the larger forecasts at 5.3M sqkm. arcus.org/sipn/sea-ice-o…pic.twitter.com/kgaROTK7Yr

I'm not that impressed either with the dipole that is forecasted for the rest of the week and maybe into early next week. It's going to help pick up the melt again but it's kind of an ugly dipole...low pressure still over Greenland and the high is centered more over the Beaufort/Chukchi rather than over the CAB and Greenland and it's not that strong.  Usually like to see 1030+ or if not, a very strong gradient between Greenland and Siberian coast to sweep lots of warm air over the pack...but we don't really get either. 

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1 hour ago, ORH_wxman said:

I'm not that impressed either with the dipole that is forecasted for the rest of the week and maybe into early next week. It's going to help pick up the melt again but it's kind of an ugly dipole...low pressure still over Greenland and the high is centered more over the Beaufort/Chukchi rather than over the CAB and Greenland and it's not that strong.  Usually like to see 1030+ or if not, a very strong gradient between Greenland and Siberian coast to sweep lots of warm air over the pack...but we don't really get either. 

Also a pretty impressive slow down in the melt near Alaska for late June.

Sea ice extent around Alaska now running close to the long term average for late June, (passive microwave data from @NSIDC). Early melt in the srn Chukchi Sea has stalled farther north and meltout in the Beaufort Sea is only slowly spreading west. #Arctic @akwx @Climatologist49 pic.twitter.com/d3rbwGXJvV
 
DgiqlfqU8AA7SYl.jpg-small.jpg.dff0b920732742dcb2c03402861c87eb.jpg
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8 hours ago, CAD_Wedge_NC said:

This is a critical time for tracking ice levels. What are they changing/replacing/adjusting? If the data comes in grossly different after the so-called "maintenance", there will be a lot of skeptical folks out there.

I'm not sure exactly what they are doing but previously when SSMI/S has been out, the data didn't look suspicious when it came back online so I wouldn't be too worried. I'd expect a definite uptick in losses though if it's out for 3-4 days and then comes back because the weather is turning more hostile up there in the next day or two. 

1 hour ago, bluewave said:

Also a pretty impressive slow down in the melt near Alaska for late June.

Sea ice extent around Alaska now running close to the long term average for late June, (passive microwave data from @NSIDC). Early melt in the srn Chukchi Sea has stalled farther north and meltout in the Beaufort Sea is only slowly spreading west. #Arctic @akwx @Climatologist49 pic.twitter.com/d3rbwGXJvV
 
DgiqlfqU8AA7SYl.jpg-small.jpg.dff0b920732742dcb2c03402861c87eb.jpg

The Chukchi/Beaufort region was by far the most vulnerable coming into the season with the later refreeze there this past winter...the ice was pretty thin. Esp the Chukchi. The huge stall there in June is going to protect the adjacent CAB that could have been taking on a very early assault had the Chukchi melted out very early. 

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12 hours ago, ORH_wxman said:

I'm not sure exactly what they are doing but previously when SSMI/S has been out, the data didn't look suspicious when it came back online so I wouldn't be too worried. I'd expect a definite uptick in losses though if it's out for 3-4 days and then comes back because the weather is turning more hostile up there in the next day or two. 

The Chukchi/Beaufort region was by far the most vulnerable coming into the season with the later refreeze there this past winter...the ice was pretty thin. Esp the Chukchi. The huge stall there in June is going to protect the adjacent CAB that could have been taking on a very early assault had the Chukchi melted out very early. 

A rare colder than normal month in that region in what has been a sea of record warmth.

 

Technical: ongoing cool wx at Utqiaġvik, Alaska is the largest negative departure of the 30-day running daily standardized temp anomaly since late summer 2014. Illustrates nicely the control by sea ice on Arctic coastal air temps. #akwx #Arctic @Climatologist49 @CinderBDT907pic.twitter.com/PK380UAnXW
 
1pm Friday, Utqiaġvik (Barrow) Alaska hits 40F (4C) for the first time this year. This ties with 1955 as the fifth latest “first 40” in the past 98 years. #akwx@Climatologist49 @CinderBDT907
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Yeah weird, I thought we'd stop getting data, but it's still flowing in. Melt picked up big time though....1 day loss was 256k (!!). Largest by far yet this season for area loss.

 

2007: -782k

2008: -308k

2009: +323k

2010: -1.08 million

2011: -449k

2012: -1.06 million

2013: +64k

2014: -216k

2015: -253k

2016: -714k

2017: -470k

 

Obviously still a ton of work to do to be in contention for a top 5 year despite the big one day area loss.

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13 hours ago, ORH_wxman said:

Yeah weird, I thought we'd stop getting data, but it's still flowing in. Melt picked up big time though....1 day loss was 256k (!!). Largest by far yet this season for area loss.

 

2007: -782k

2008: -308k

2009: +323k

2010: -1.08 million

2011: -449k

2012: -1.06 million

2013: +64k

2014: -216k

2015: -253k

2016: -714k

2017: -470k

 

Obviously still a ton of work to do to be in contention for a top 5 year despite the big one day area loss.

Not reliable data.... No way.

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8 hours ago, CAD_Wedge_NC said:

Not reliable data.... No way.

Today's data is def contaminated...it's showing a loss of 750k, lol...but yesterday's was not that weird...we've seen 250k drops before many years (not every year though)...esp when you consider that more than half of that was from the Hudson/Baffin alone which were running pretty high. Today's data is no good though, so the outage is definitely here. We'll just have to see how long it lasts. Hopefully we're back up in 2-3 days. The concentration map got all mucked up in the CAB and CAA, so it's clear they are doing something with it.

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24 minutes ago, DaculaWeather said:

Makes you wonder what they ARE doing to it and why. 

The current SSMI/S satellite is beyond its lifespan so it needs maintenance more often now. 

There's no conspiracy to hide data. It wouldn't matter anyway...we have AMSR2 up there which is completely unrelated. So even if SSMI/S never came back or had "conspiracy" data, we would still easily track the ice sheet through AMSR2 to the minimum. AMSR2 is better anyway with the exception of June when the inferior SSMI/S sensor gets fooled more easily by melt ponds so it allows us to predict better...once in July and August, we start looking more at AMSR2 (which is tracked by sites like JAXA and U Bremen)

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