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ORH_wxman

Arctic Sea Ice Extent, Area, and Volume

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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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5 hours ago, ORH_wxman said:

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

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/

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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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1 hour ago, AfewUniversesBelowNormal said:

Do you really think 7th right now? It's kind of a fancy number by the way. What are the clouds like where you are?

NSIDC northern hemisphere sea ice extent is currently in 7th place for 6.25.2018, whereas area for the date is 11th place. This weeks dipole is modeled to be transient with a weak pressure gradient. Extrapolating today's data it does not look like we will finish in the top 10 for NSIDC northern hemisphere sea ice extent. The weather pattern can always change, however as we get closer to the minimum the more low pressure tends to dominate. The arctic cryosphere is compact and will eventually move towards area when the ice spreads out more. I predict an eleventh place finish for NSIDC northern hemisphere sea ice extent at the 2018 minimum.

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The NSIDC northern hemisphere arctic sea ice extent value for 6.26.2018 is 10.297 millions of square kilometers (gain of 56 thousand square kilometers). This places 2018 northern hemisphere sea ice extent in 8th place for the date.

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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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The AMO & 8/1 ice extent, for 1979-2017 when compared to 1979-2016, saw an increased r-value relationship. Jan-May AMO value is down 0.16 from last year (+0.08 v. +0.24). Theoretically worth around 0.5 million sq km in sea ice extent.

NdNUQBI.png

 

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NSIDC area data looks to be "correcting" back to more normal numbers...we saw an increase of area of 471k after a drop of 750k yesterday...so it's a 2 day net drop of 279k which is 139k per day....much more normal for this time of the year.

Still not totally sure if the data is good, but here's where we stand if it is:

 

2007: -412k

2008: -130k

2009: +388k

2010: -909k

2011: -579k

2012: -1.05 million

2013: +26k

2014: -141k

2015: -226k

2016: -587k

2017: -260k

 

We're basically running neck and neck with 2013 still with two days remaining in the month.

 

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On 6/28/2018 at 9:30 AM, DaculaWeather said:

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

 

lol @ anybody that doesn't think things are rigged these days.

their goal is to keep you stupid.  And give BS responses that sound smart but are just to keep people stupid.

the same way people in medical school are trained....that practically no diseases are curable these days, without BS prescriptions that make people more sick.

sports as well...many games are rigged.

our economy runs on stupid.  did I forget to mention the stock market?  

you get the drift.

wake up..

 

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On 6/28/2018 at 7:30 AM, DaculaWeather said:

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

Don't know how Will is so patient with comments like above. But take a look at the company you keep... scientists have a conspiracy to pretend the ice is gone (easily disproven by satellite picture, airplane and boat traffic) .... and prescription drugs make people more sick... there you have it people... the paranoid American far-right

19 hours ago, Sophisticated Skeptic said:

 

lol @ anybody that doesn't think things are rigged these days.

their goal is to keep you stupid.  And give BS responses that sound smart but are just to keep people stupid.

the same way people in medical school are trained....that practically no diseases are curable these days, without BS prescriptions that make people more sick.

sports as well...many games are rigged.

our economy runs on stupid.  did I forget to mention the stock market?  

you get the drift.

wake up..

 

 

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