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Arctic Sea Ice Extent, Area, and Volume


ORH_wxman
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This was the warmest melt season on record. A new paper is out on the continuing Atlantification of the Arctic Ocean. This year the sea ice edge made it to 85°N on the Atlantic side.

 

 


https://nsidc.org/arcticseaicenews/

Atlantification continues

As discussed in a recent paper in the Journal of Climate led by colleague Igor Polyakov of the University of Alaska, the process of “Atlantification” of the Arctic Ocean, first noted in the Barents Sea, is continuing, with significant effects on the sea ice cover during the winter season in the Eastern Eurasian Basin. The relatively fresh surface layer of the Arctic Ocean is underlain by warm, salty water that is imported from the northern Atlantic Ocean. The cold fresh surface layer, because of its lower density, largely prevents the warm, salty Atlantic waters from mixing upwards. However, the underlying Atlantic water appears to have moved closer to the surface in recent years, reducing the density contrast with the water above it. Recent observations show this warm water “blob,” usually found at about 150 meters (492 feet) below the surface, has shifted within 80 meters (263 feet) of the surface. This has resulted in an increase in the upward winter ocean heat flow to the underside of the ice from typical values of 3 to 4 watts per square meter in 2007 to 2008 to greater than 10 watts per square meter from 2016 to 2018. Polyakov estimates that this is equivalent to a two-fold reduction in winter ice growth.

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19 minutes ago, bluewave said:

This was the warmest melt season on record. A new paper is out on the continuing Atlantification of the Arctic Ocean. This year the sea ice edge made it to 85°N on the Atlantic side.

 

 


https://nsidc.org/arcticseaicenews/

Atlantification continues

As discussed in a recent paper in the Journal of Climate led by colleague Igor Polyakov of the University of Alaska, the process of “Atlantification” of the Arctic Ocean, first noted in the Barents Sea, is continuing, with significant effects on the sea ice cover during the winter season in the Eastern Eurasian Basin. The relatively fresh surface layer of the Arctic Ocean is underlain by warm, salty water that is imported from the northern Atlantic Ocean. The cold fresh surface layer, because of its lower density, largely prevents the warm, salty Atlantic waters from mixing upwards. However, the underlying Atlantic water appears to have moved closer to the surface in recent years, reducing the density contrast with the water above it. Recent observations show this warm water “blob,” usually found at about 150 meters (492 feet) below the surface, has shifted within 80 meters (263 feet) of the surface. This has resulted in an increase in the upward winter ocean heat flow to the underside of the ice from typical values of 3 to 4 watts per square meter in 2007 to 2008 to greater than 10 watts per square meter from 2016 to 2018. Polyakov estimates that this is equivalent to a two-fold reduction in winter ice growth.

Amazing, I wonder how long it will take the fIrst commercial venture, that sees good ($$) In any condition, to advertise romantic cruises to the pole under the midnight sun. As always .....

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On 7/2/2020 at 1:54 PM, ORH_wxman said:

We have the final June numbers in....here's the breakdown of what the minimum in 2020 would be if we followed the same path as every other year:

 

 

 

So if we followed the same path that 2019 followed after 6/30, we would finish at 3 million sq km of sea ice area. The post-2007 average path followed is 2.78 million sq km which is what I will use as my baseline.

However, there are two factors that will cause me to lower this baseline a bit. First, is that we had a 340k(!!) loss on 7/1....and second, we have a very hostile pattern for the ice. We're currently into a nuclear dipole pattern which would continue to assault the ice for the next week. This will help increase melting and melt ponds while the sun angle is still pretty high in the arctic.

 

Normally, I would put the chances of passing 2012's minimum of 2.228 million sq km at close to 0% based simply on the chart above. But I'll give it an outside shot of happening this year given the current pattern and the huge loss on 7/1.

 

My prediction will be for minimum sea ice area in 2020 is 2.5 million sq km +/- 300k. A minimum of 2.5 million sq km would be 3rd lowest. The top two are 2012 (2.228) and 2016 (2.463).

Sea ice extent is a little more fickle since it can depend on compaction vs area which is very straight forward. But for the minimum daily NSIDC sea ice extent, I'll go with 3.8 million sq km +/- 500k. I use larger error bars on the extent due to the much higher standard deviation.

 

 

Update as we get close to the minimums....

 

Current NSIDC area is 2.74 million sq km and current extent is 3.94 million sq km. These should decline a bit further to the min (prob sometime in a week to 10 days historically....perhaps slightly sooner for area).

Pretty happy with the predictions so far....we'll see if there are any late season surprises. 

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On 8/30/2020 at 11:43 PM, donsutherland1 said:

Arctic sea ice extent fell to 3.995 million square kilometers on JAXA. That makes 2020 the second consecutive year that will have a minimum extent below 4.000 million square kilometers and the third such year on record. 

I saw a WaPo article that mentioned 2012 and the record melt off that occurred that year and then mentioned Sandy and the anomalous track it took.  Do you believe the two are connected, Don (research seems to be pointing this way with regards to strong blocking and arctic ice melt) and if so, do you think a similar melt off this year could result in another storm like that come October (when these kinds of storms are most likely to happen?)

 

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50 minutes ago, LibertyBell said:

I saw a WaPo article that mentioned 2012 and the record melt off that occurred that year and then mentioned Sandy and the anomalous track it took.  Do you believe the two are connected, Don (research seems to be pointing this way with regards to strong blocking and arctic ice melt) and if so, do you think a similar melt off this year could result in another storm like that come October (when these kinds of storms are most likely to happen?)

 

There is some research indicating that Arctic Amplification also has an impact on the summer weather pattern in addition to that of the fall. In general, one line of thought is that it is leading to greater persistence of events due to a wavier and slowing jet stream. 

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9 hours ago, donsutherland1 said:

There is some research indicating that Arctic Amplification also has an impact on the summer weather pattern in addition to that of the fall. In general, one line of thought is that it is leading to greater persistence of events due to a wavier and slowing jet stream.

The zonal wind anomalies show a stronger westerly jet and are twice as large as the meridional wind anomalies at 250 mb suggesting a less wavier jet stream at 250 mb in the last 10 years. This whole "wavier" jet stream is unfounded and a convenient excuse when cold air comes farther south. You can still blame it on global warming. This is laughable.  see: 

QfrMFB7tyS.png.4c21db8ff0fa14ebc9db540fcbe86def.png

FCKLfKyc70.png.010bf7b793e78b5720160e2c1613976d.png

 

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1 hour ago, blizzard1024 said:

The zonal wind anomalies show a stronger westerly jet and are twice as large as the meridional wind anomalies at 250 mb suggesting a less wavier jet stream at 250 mb in the last 10 years. This whole "wavier" jet stream is unfounded and a convenient excuse when cold air comes farther south. You can still blame it on global warming. This is laughable.  see: 

QfrMFB7tyS.png.4c21db8ff0fa14ebc9db540fcbe86def.png

FCKLfKyc70.png.010bf7b793e78b5720160e2c1613976d.png

 

Two papers:

https://iopscience.iop.org/article/10.1088/1748-9326/10/1/014005

https://www.nature.com/articles/s41467-018-05256-8.epdf

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4 hours ago, donsutherland1 said:

Yay. These folks just re-discovered the Arctic oscillation. It was negative in the 1960s and 70s too... a cold global period.   Papers are non-sense. Can't believe what gets published these days. 

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First time since 2012 that the 5 day NSIDC extent dropped below 4 million sq km. Also the first 5 year period with 3 years below 4.2 million sq km.

9-6-20.......3.928

September

5-day date
3.387 2012-09-17
4.155 2007-09-18
4.165 2016-09-10
4.192 2019-09-18

120DE05B-98F5-45B8-8680-3F62A6B6F4A7.thumb.png.693030c43a43d2d3422566717f9e9f24.png

 

 

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1010 WINS Radio reported:

An enormous chunk of Greenland’s ice cap has broken off in the far northeastern Arctic, a development that scientists say is evidence of rapid climate change.

The glacier section that broke off is 110 square kilometers (42.3 square miles). It came off of the fjord called Nioghalvfjerdsfjorden, which is roughly 80 kilometers (50 miles) long and 20 kilometers (12 miles) wide, the National Geological Survey of Denmark and Greenland said Monday.

The glacier is at the end of the Northeast Greenland Ice Stream, where it flows off the land and into the ocean.

The BBC has an article on this development. That article can be found at:

https://www.bbc.com/news/science-environment-54127279

 

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On 7/2/2020 at 1:54 PM, ORH_wxman said:

We have the final June numbers in....here's the breakdown of what the minimum in 2020 would be if we followed the same path as every other year:

2020_SIA_forecast.png.8de2848a27df8932058713306a129dd8.png

 

 

So if we followed the same path that 2019 followed after 6/30, we would finish at 3 million sq km of sea ice area. The post-2007 average path followed is 2.78 million sq km which is what I will use as my baseline.

However, there are two factors that will cause me to lower this baseline a bit. First, is that we had a 340k(!!) loss on 7/1....and second, we have a very hostile pattern for the ice. We're currently into a nuclear dipole pattern which would continue to assault the ice for the next week. This will help increase melting and melt ponds while the sun angle is still pretty high in the arctic.

 

Normally, I would put the chances of passing 2012's minimum of 2.228 million sq km at close to 0% based simply on the chart above. But I'll give it an outside shot of happening this year given the current pattern and the huge loss on 7/1.

 

My prediction will be for minimum sea ice area in 2020 is 2.5 million sq km +/- 300k. A minimum of 2.5 million sq km would be 3rd lowest. The top two are 2012 (2.228) and 2016 (2.463).

Sea ice extent is a little more fickle since it can depend on compaction vs area which is very straight forward. But for the minimum daily NSIDC sea ice extent, I'll go with 3.8 million sq km +/- 500k. I use larger error bars on the extent due to the much higher standard deviation.

 

 

Final daily minimum NSIDC extent has likely been reached....and it was 3.71 million sq km on 9/13. This is the second lowest minimum behind 2012's 3.34 million sq km.

Minimum area may or may not have been reached. Current minimum is 2.59 million sq km on 9/15. This is the 3rd lowest behind 2012 (2.23) and 2016 (2.46). I will update if we slip any further, though we're unlikely to change the ranking as it's very late in the season for large moves.

 

The predictions this year based on SIA at the end of June proved to be very accurate and both were off by less than 100k.

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12 hours ago, donsutherland1 said:

On JAXA, Arctic sea ice extent rose to 3.735 million square kilometers. The 2020 minimum figure was 3.555 million square kilometers. That figure will very likely be the final minimum extent for 2020.

It seems like the average minimum is around the first day of fall now?

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8 minutes ago, LibertyBell said:

It seems like the average minimum is around the first day of fall now?

That's pretty late though it does happen occasionally. I don't have the jaxa dataset handy, but here are the minimum dates for NSIDC extent:

2020: 9/13

2019: 9/17

2018: 9/21

2017: 9/13

2016: 9/7

2015: 9/8

2014: 9/16

2013: 9/13

2012: 9/16

2011: 9/8

2010: 9/19

2009: 9/12

2008: 9/18

2007: 9/17

2006: 9/14

2005: 9/20

2004: 9/18

2003: 9/17

2002: 9/18

2001: 9/19

2000: 9/11

1999: 9/11

1998: 9/17

1997: 9/3

1996: 9/10

1995: 9/4

1994: 9/5

1993: 9/13

1992: 9/7

1991: 9/16

1990: 9/21

1989: 9/22

1988: 9/11

1987: 9/2

1986: 9/6

1985: 9/9

1984: 9/16

1983: 9/8

1982: 9/9

1981: 9/10

1980: 9/5

1979: 9/21

 

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10 minutes ago, ORH_wxman said:

That's pretty late though it does happen occasionally. I don't have the jaxa dataset handy, but here are the minimum dates for NSIDC extent:

2020: 9/13

2019: 9/17

2018: 9/21

2017: 9/13

2016: 9/7

2015: 9/8

2014: 9/16

2013: 9/13

2012: 9/16

2011: 9/8

2010: 9/19

2009: 9/12

2008: 9/18

2007: 9/17

2006: 9/14

2005: 9/20

2004: 9/18

2003: 9/17

2002: 9/18

2001: 9/19

2000: 9/11

1999: 9/11

1998: 9/17

1997: 9/3

1996: 9/10

1995: 9/4

1994: 9/5

1993: 9/13

1992: 9/7

1991: 9/16

1990: 9/21

1989: 9/22

1988: 9/11

1987: 9/2

1986: 9/6

1985: 9/9

1984: 9/16

1983: 9/8

1982: 9/9

1981: 9/10

1980: 9/5

1979: 9/21

 

It's interesting that 1979 was one of our latest minimum ice extents, especially considering that 1979 was one of our coldest winters, almost historic in terms of how widespread the cold was in winter 1979-80!

 

edit that was 1978-79 not 1979-80 lol...I do remember that there was an anomalous early season snow event in the Mid Atlantic in October 1979 though....the area from DC to Philly got around 2-4" of snow?

 

 

Either way a 9/20 or later min ice extent day seems to be about a once a decade occurrence, except for the notable exception of 1989 and 1990, when it happened in back to back years, the height of our famous snow drought (high solar influence back then?)

 

 

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I’m not sure if the below paper has been posted here, but it allows for comparisons of Arctic sea ice volume during the first half of the 20th century, including the 1920-40 Arctic warming, and the rapid declines in volume today. The paper is:

Arctic Sea Ice Volume Variability over 1901–2010: A Model-Based Reconstruction

https://journals.ametsoc.org/jcli/article/32/15/4731/343909/Arctic-Sea-Ice-Volume-Variability-over-1901-2010-A

 

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