Arctic Sea Ice Extent, Area, and Volume

[etudiant]

49 minutes ago, forkyfork said:

climate change is cancelled!!!

At least for the northern hemisphere.

I believe the Antarctic is considerably less icy than usual.

[chubbs]

11 hours ago, stadiumwave said:

 

Doesn't look great to me. Very unscientific analysis - the trend since 2004 is much more uncertain than the trend since 1979; and doesn't look negligble either. Note that volume anomaly is higher in winter.

[bdgwx]

Annual mean sea ice extent came in at 10.547e6 km2 for 2021.  Even with a relativity great year it is still about 5% below the 1991-2020 climatological average of 11.082e6 km2. That is 9th lowest in the 42 year satellite record and if we use Walsh et al. 2016 we can extend that back 170 years. This is the first year since 2015 since annual mean sea ice extent was > 10.5e6 km2. Remember, back in 2001 the IPCC predicted that this threshold would not be crossed until about 2040. It first happened in 2007 and then again 7 other times prior to 2021. It is pretty remarkable to think that with the pattern we've seen in the Arctic this year we should have seen anomalously high extents yet we still almost dropped below this threshold again.

 

[Typhoon Tip]

We just need this so dubbed 'Dooms day glacier' to go ahead and unleash the back-held weight of a small continent in ice, ...and have it cataclysmically slide one afternoon into the sea...  effectively setting off a global two foot tsunamis that doesn't go back out to sea.

 

[lee59]

Good to see Arctic sea ice extent the highest since 2012. Actually above the 2010s average.  Of course the question is, will it last.

[StormchaserChuck!]

I want us to just melt to get to some normal climate conditions. we've been in this computer matrix for a while. Let it melt. alot. take the satelites down, etc. dont start controlling your own place.. lol. Stop the freeze-melt by melting completely. 

[IUsedToHateCold]

On 1/10/2022 at 11:58 AM, lee59 said:

Good to see Arctic sea ice extent the highest since 2012. Actually above the 2010s average.  Of course the question is, will it last.

Multiple La Nina’s cooling the globe in the past 10 years. They won’t keep up with AGW though. There will likely be a big melt like 2012 in the next five years and the bar will set even lower. 

[csnavywx]

On 1/1/2022 at 6:14 AM, chubbs said:

Doesn't look great to me. Very unscientific analysis - the trend since 2004 is much more uncertain than the trend since 1979; and doesn't look negligble either. Note that volume anomaly is higher in winter.

If he's tweeting it, it's a sure sign that we're near the top. These folks usually come out of the woodwork right before it tanks. Great contrarian signal if nothing else.

[FPizz]

On 2/4/2022 at 11:29 PM, csnavywx said:

If he's tweeting it, it's a sure sign that we're near the top. These folks usually come out of the woodwork right before it tanks. Great contrarian signal if nothing else.

Happens both ways.  When it is up, you hear what global warming.  When it is down, you hear how we are all doomed.  

[bluewave]

A recent study found that the extreme drop in MYI coverage with the  2007 season has slowed the rate of new extent record minimums in September. The last record minimum extent in September occurred back in 2012. But we came close to that record a few years ago. The thinner ice makes it easier for the winds to push around the extents quite a bit from year to year. So we can have large differences between years like 2012 and 2013 and 2020 and 2021. The big story is that even the most favorable seasons since 2007 have never been able to approach early 2000s extents and volume levels. So it appears that the fundamental shift in the Arctic has already occurred back in 2007. While we’ll eventually surpass 2012 and head toward an ice free season in the future as the planet warms, 2007 may be more significant than the first technically ice free season below 1 million sq km. 

https://iopscience.iop.org/article/10.1088/1748-9326/aae3ec

• From the peak MYI coverage in 2002 to the end of our record in 2017, the Arctic has lost more than 2 × 10⁶ km², a decrease of 50%; MYI now covers less than one-third of the Arctic Ocean. As with ice volume, the largest decline in MYI coverage followed the record-setting end-of-summer ice extent in 2007. In addition to annual ice export, recent losses of MYI are due to melt of MYI advected into the southern Beaufort Sea from the north coast of Greenland and the CAA, the source region of the thickest and most deformed ice in the Arctic Ocean.

https://climate.nasa.gov/news/2817/with-thick-ice-gone-arctic-sea-ice-changes-more-slowly/

The Arctic Ocean's blanket of sea ice has changed since 1958 from predominantly older, thicker ice to mostly younger, thinner ice, according to new research published by NASA scientist Ron Kwok of the Jet Propulsion Laboratory, Pasadena, California. With so little thick, old ice left, the rate of decrease in ice thickness has slowed. New ice grows faster but is more vulnerable to weather and wind, so ice thickness is now more variable, rather than dominated by the effect of global warming.

Working from a combination of satellite records and declassified submarine sonar data, NASA scientists have constructed a 60-year record of Arctic sea ice thickness. Right now, Arctic sea ice is the youngest and thinnest its been since we started keeping records. More than 70 percent of Arctic sea ice is now seasonal, which means it grows in the winter and melts in the summer, but doesn't last from year to year. This seasonal ice melts faster and breaks up easier, making it much more susceptible to wind and atmospheric conditions.

Kwok's research, published today in the journal Environmental Research Letters, combined decades of declassified U.S. Navy submarine measurements with more recent data from four satellites to create the 60-year record of changes in Arctic sea ice thickness. He found that since 1958, Arctic ice cover has lost about two-thirds of its thickness, as averaged across the Arctic at the end of summer. Older ice has shrunk in area by almost 800,000 square miles (more than 2 million square kilometers). Today, 70 percent of the ice cover consists of ice that forms and melts within a single year, which scientists call seasonal ice.

Sea ice of any age is frozen ocean water. However, as sea ice survives through several melt seasons, its characteristics change. Multiyear ice is thicker, stronger and rougher than seasonal ice. It is much less salty than seasonal ice; Arctic explorers used it as drinking water. Satellite sensors observe enough of these differences that scientists can use spaceborne data to distinguish between the two types of ice.

Thinner, weaker seasonal ice is innately more vulnerable to weather than thick, multiyear ice. It can be pushed around more easily by wind, as happened in the summer of 2013. During that time, prevailing winds piled up the ice cover against coastlines, which made the ice cover thicker for months.

The ice's vulnerability may also be demonstrated by the increased variation in Arctic sea ice thickness and extent from year to year over the last decade. In the past, sea ice rarely melted in the Arctic Ocean. Each year, some multiyear ice flowed out of the ocean into the East Greenland Sea and melted there, and some ice grew thick enough to survive the melt season and become multiyear ice. As air temperatures in the polar regions have warmed in recent decades, however, large amounts of multiyear ice now melt within the Arctic Ocean itself. Far less seasonal ice now thickens enough over the winter to survive the summer. As a result, not only is there less ice overall, but the proportions of multiyear ice to seasonal ice have also changed in favor of the young ice.

Seasonal ice now grows to a depth of about six feet (two meters) in winter, and most of it melts in summer. That basic pattern is likely to continue, Kwok said. "The thickness and coverage in the Arctic are now dominated by the growth, melting and deformation of seasonal ice."

The increase in seasonal ice also means record-breaking changes in ice cover such as those of the 1990s and 2000s are likely to be less common, Kwok noted. In fact, there has not been a new record sea ice minimum since 2012, despite years of warm weather in the Arctic. "We've lost so much of the thick ice that changes in thickness are going to be slower due to the different behavior of this ice type," Kwok said.

Kwok used data from U.S. Navy submarine sonars from 1958 to 2000; satellite altimeters on NASA's ICESat and the European CryoSat-2, which span from 2003 to 2018; and scatterometer measurements from NASA's QuikSCAT and the European ASCAT from 1999 to 2017.

 

[etudiant]

Afaik, the polar ice, including the multi year ice, gradually rotates around the pole following the ocean currents.

There are exit paths from the Arctic Ocean, such as the Fram Straits, through which masses of even multi year ice can be lost.

The Titanic was a casualty of one such large outflow event.

It suggests that changes in ocean flows are a substantial factor in determining the durability and extent of Arctic multi year ice, possibly amplifying the effects of temperature.

[LibertyBell]

6 hours ago, etudiant said:

Afaik, the polar ice, including the multi year ice, gradually rotates around the pole following the ocean currents.

There are exit paths from the Arctic Ocean, such as the Fram Straits, through which masses of even multi year ice can be lost.

The Titanic was a casualty of one such large outflow event.

It suggests that changes in ocean flows are a substantial factor in determining the durability and extent of Arctic multi year ice, possibly amplifying the effects of temperature.

I wonder how slowing down of ocean currents, like the gulf stream, will impact it?

 

Maybe ocean currents are slowing in one area and speeding up in another to balance it out?

 

[bluewave]

The multiyear ice for 2021 finished at the 2nd lowest behind 2012. So just looking at the extent rebound from 2020 can be a bit deceptive. The amount of MYI is one of the key indicators as to how much the Arctic has warmed. 
 

https://arctic.noaa.gov/Report-Card/Report-Card-2021/ArtMID/8022/ArticleID/945/Sea-Ice

Sea ice age

Sea ice drifts around the Arctic Ocean, forced by winds and ocean currents, growing and melting thermodynamically. Ice convergence can also lead to dynamic thickening (i.e., ridging and rafting) while ice divergence during winter exposes open water within which new ice can form. Age is a proxy for thickness as multiyear ice (ice that survives at least one summer melt season) grows thicker over successive winter periods. Age is here presented over the Arctic Ocean domain (Fig. 3, inset) for the period 1985-2021. In the week before the 2021 annual minimum extent, when the age values of the remaining sea ice are incremented by one year, the amount of multiyear ice remaining in the Arctic Ocean was the second lowest on record (above only 2012). The September multiyear sea ice extent declined from 4.40 million km² in 1985 to 1.29 million km² in 2021 (Fig. 3). Over the same period, the oldest ice (>4 years old) declined from 2.36 million km² to 0.14 million km². In the 37 years since records began in 1985, the Arctic Ocean has changed from a domain dominated by multiyear ice to one where first-year ice prevails. A younger ice cover implies a thinner, less voluminous ice pack.

 

[bdgwx]

On the other side of the globe SH sea ice has quietly moved into 1st place in terms lowest extent on this date Feb. 8th according to NSIDC. We cannot eliminate the possibility of a new record low minimum down there within the next month.

[bdgwx]

Per NSIDC daily sea ice extent in the Antarctic region has reached a new record low minimum value on Feb 15th, 2022 of 2.034e6 km2. This breaks the old record set on Mar 1st, 2017 of 2.080e6 km2.

[StormchaserChuck!]

[so_whats_happening]

I have a bad feeling about the Arctic coming up this summer. Early season conditioning taking place while the Atlantic front is just a mess overall at or less then 1m thick ice over that way. With everything besides the end of January storm being about on par for a season it looked like things were maybe setting up for a better year. Hope this doesn't play out as such.

[LibertyBell]

On 2/16/2022 at 9:21 AM, bdgwx said:

Per NSIDC daily sea ice extent in the Antarctic region has reached a new record low minimum value on Feb 15th, 2022 of 2.034e6 km2. This breaks the old record set on Mar 1st, 2017 of 2.080e6 km2.

Of note is that it can still get lower.  I wonder what the yearly minimum will be, that usually happens in March just before Fall starts there?

I think it's likewise in September for the Arctic when our Fall starts.

[bdgwx]

We're probably getting pretty close to the Antarctica minimum. The NSIDC 5-day average is at 1.929e6 km2 as of Feb. 24th.

[bluewave]

New observations find much greater decline  in Arctic sea ice thickness than scientists expected.

 

https://www.washington.edu/news/2022/03/10/newest-satellite-data-shows-remarkable-decline-in-arctic-sea-ice-over-just-three-years/

The newest technology, a combination of ICESat-2 lidar data and CryoSat-2 radar data, is able for the first time to estimate the depth of the snow on top of the Arctic sea ice. Using snow depth and the height of sea ice exposed above water, the study found that multiyear Arctic sea ice lost 16% of its winter volume, or approximately half a meter (about 1.5 feet) of thickness, in the three years since the launch of ICESat-2 in 2018.

“We weren’t really expecting to see this decline, for the ice to be this much thinner in just three short years,” said lead author Sahra Kacimi at CalTech’s Jet Propulsion Laboratory.

[ORH_wxman]

Almost time to start tracking the sea ice area daily....I usually wait until after 6/15 to do that as we're still a bit early. For a refresher for those who don't follow this every year, the NSIDC sea ice area at the end of June is able to predict final minimum extent and area quite skillfully because the NSIDC algorithm is relying on SSMI/S satellite data which gets fooled by melt ponding into thinking there is open water....something that the other satellites aren't susceptible to. The reason that is important is melt ponding is an excellent predictor of sea ice extent/area minimum. If we had perfectly accurate measurements of melt ponding publicly available, we wouldn't have to use NSIDC area, but for now, NSIDC is a good proxy.

 

Here's where other years stand in relation to 2022 NSIDC area as of today:

2021: -210k

2020: +160k

2019: -100k

2018: +110k

2017: +10k

2016: -500k

2015: +90k

2014: +220k

 

You can see there is a mishmash of results there that doesn't tell us much yet. 2022 has more ice than last year at this time but less than 2020 which was a huge melt year. However, the real separation starts occurring once we get toward 6/20 and beyond. Years like 2020 went absolutely nuclear over the next couple weeks. I'll prob update these again in about a week and then do more frequent updates as we get into the final 10 days of the month.

 

 

 

[bdgwx]

New record low extent for June 10th per NSIDC down in the Antarctic region. 11.642e6 km^2.

[bluewave]

An early June statistical model forecast for the average September Arctic sea ice extent came in at 4.5 million sq km.

 

 

[bdgwx]

1 hour ago, Weatherdude88 said:

What is the reason for your pedaling of propaganda and misinformation? Perhaps you have an agenda?

NSIDC Southern Hemisphere sea ice extent for 6.10.2022, has more sea ice extent than 6.10.1980 (42 years ago).

I see 11.813e6 km^2 for June 10th, 1980. Note that this is the simple linear interpolation of the June 9 and June 11 values of 11.665e6 and 11.961e6 km^2 respectively.

The closest to 11.642e6 km^2 is 11.646e6 km^2 in 2019.

Can you double check your source? I believe the 5.142e6 km^2 value you see is for April 10th, 2022 which is the 100th day of the year.

[bdgwx]

48 minutes ago, Weatherdude88 said:

Click on this link. 

 

https://nsidc.org/arcticseaicenews/charctic-interactive-sea-ice-graph/

 

Hide all except for 2022 and 1980. You will see 2022 has remained above 1980. 

This is directly from NSIDC's website.

That graph is showing the trailing 5 day average which is different than the daily values.

BTW...the graph has a quirk where the same date from different years is shifted visually if one of the years was a leap year such as 1980. If you look closely you'll see that June 10th, 1980 was 11.49e6 km^2 whereas June 10th, 2022 was 11.459e6 km^2.  So even with the 5 day average 2022 was lower than 1980.

 

[bdgwx]

1 hour ago, Weatherdude88 said:

For 6.10.2022 the 5-day trailing average is not only higher than 1980

6.6.2022 thru 6.10.2022 = 11.459e6 km^2

6.6.1980 thru 6.10.1980 = 11.490e6 km^2

Side note...6.6.1980, 6.8.1980, and 6.10.1980 are missing so the 11.490e6 km^2 value is actually the average of 6.7.1980 and 6.9.1980 only. If we use a simple linear interpolation to fill in the missing values the 5 day average becomes 11.499e6 km^2.

[ORH_wxman]

On 6/8/2022 at 11:51 AM, ORH_wxman said:

Almost time to start tracking the sea ice area daily....I usually wait until after 6/15 to do that as we're still a bit early. For a refresher for those who don't follow this every year, the NSIDC sea ice area at the end of June is able to predict final minimum extent and area quite skillfully because the NSIDC algorithm is relying on SSMI/S satellite data which gets fooled by melt ponding into thinking there is open water....something that the other satellites aren't susceptible to. The reason that is important is melt ponding is an excellent predictor of sea ice extent/area minimum. If we had perfectly accurate measurements of melt ponding publicly available, we wouldn't have to use NSIDC area, but for now, NSIDC is a good proxy.

 

Here's where other years stand in relation to 2022 NSIDC area as of today:

2021: -210k

2020: +160k

2019: -100k

2018: +110k

2017: +10k

2016: -500k

2015: +90k

2014: +220k

 

You can see there is a mishmash of results there that doesn't tell us much yet. 2022 has more ice than last year at this time but less than 2020 which was a huge melt year. However, the real separation starts occurring once we get toward 6/20 and beyond. Years like 2020 went absolutely nuclear over the next couple weeks. I'll prob update these again in about a week and then do more frequent updates as we get into the final 10 days of the month.

 

 

 

Update (NSIDC SIA stands at 8.72 milion sq km as of 6/15):

 

2021: -90k

2020: -220k

2019: -460k

2018: +140k

2017: +110k

2016: -280k

2015: -50k

2014: +80k

2013: +190k

2012: -730k

2011: -200k

2010: -210k

2009: +660k

2008: +210k

2007: -140k

 

 

2022 is starting to fall behind the pace of loss on the top melt years like 2012, 2016, 2020, 2011, 2007, etc. Gonna need it to pick up quite a bit over the next 2 weeks to have a shot at a new record or even top 3. I think there's probably too much ice in the Beaufort/Canadian Basin/CAA this year for a huge season.

[bluewave]

The 2012 model forecast for the rate of extent decline to slow following the 2007-2012 historic losses was very impressive. 

https://tc.copernicus.org/articles/7/555/2013/tc-7-555-2013.pdf

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

A. E. West, A. B. Keen, and H. T. Hewitt

• Met Office Hadley Centre, Exeter, UK

Received: 09 May 2012 – Discussion started: 18 Jul 2012 – Revised: 04 Feb 2013 – Accepted: 18 Feb 2013 – Published: 26 Mar 2013

Abstract. The fully coupled climate model HadGEM1 produces 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 decline out to 2030, produced by two ensembles of HadGEM1 with natural and anthropogenic forcings included. These ensembles 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 relevant 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.

How to cite. West, A. E., Keen, A. B., and Hewitt, H. T.: Mechanisms causing reduced Arctic sea ice loss in a coupled climate model, The Cryosphere, 7, 555–567, https://doi.org/10.5194/tc-7-555-2013, 2013.

 

 

New paper discusses the slowdown since the last record in 2012.

 

Recent Slowdown in the Decline of Arctic Sea Ice Volume Under Increasingly Warm Atmospheric and Oceanic Conditions

Jinlun Zhang

First published: 25 August 2021

 

https://doi.org/10.1029/2021GL094780

Citations: 1

Here, 2007 is selected as a starting year to examine the slowdown of the Arctic SIV in recent years. This is based on the consideration that 2007 saw a record low summer ice extent at that time, before a new record set in 2012. Nevertheless, the selection is somewhat arbitrary, and one can certainly select a different starting year for analysis. However, moderately shifting the starting year away from 2007 (e.g., 2005, 2006, 2008, and 2009) would not fundamentally change this model study's conclusions that a slowdown of the Arctic SIV decline has occurred in recent years.

Note that the model simulated Arctic SIV drops from 1979 to a local minimum in 1982 and then peaks in 1987 (Figure 2a). There is no significant trend in SIV during the period 1979–1987. While there is no significant trend in SIV either during the period 2007–2020, the later period differs from the early period 1979–1987 in two key aspects: (a) SIV in 2007–2020 is much lower than in 1979–1987, and (b) SAT and UOT are climbing increasingly higher in 2007–2020, while dropping in 1979–1987. The thinner ice cover during 2007–2020 leads the ice export and growth processes to play a role in serving as a negative feedback to slow down the SIV decline, which is not seen in 1979–1987. It is expected that such a role may become more prominent in the future. In other words, the slowdown of the Arctic SIV decline may continue for some time in the future unless a stronger Arctic warming than the present would occur. Whether it is true remains to be seen through enhanced observations and modeling.

 

[ORH_wxman]

Update....

NSIDC SIA stood at 8.65 million sq km as of 6/16

How other years compared to 2022 on this date:

2021: -320k

2020: -410k

2019: -520k

2018: +50k

2017: +120k

2016: -330k

2015: -70k

2014: +150k

2013: +110k

2012: -800k

2011: -330k

2010: -190k

2009: +670k

2008: +180k

2007: -170k

[GaWx]

18 hours ago, ORH_wxman said:

Update....

NSIDC SIA stood at 8.65 million sq km as of 6/16

How other years compared to 2022 on this date:

2021: -320k

2020: -410k

2019: -520k

2018: +50k

2017: +120k

2016: -330k

2015: -70k

2014: +150k

2013: +110k

2012: -800k

2011: -330k

2010: -190k

2009: +670k

2008: +180k

2007: -170k

 So, that is a nice gain vs the mean of those years to +120 vs the +70 of 24 hours earlier.

 It has been cooler than the 1958-2002 mean north of 80N averaged out on most days since late April making it the coolest during that period averaged out in many years. Furthermore, though subtle since variance in summer is small, the June 17th daily mean temperature is the coolest on June 17th since 2014. As long as the north of 80N mean temperature remains even just slightly cooler than the 1958-2002 mean, the chances of a sustained rapid pace of loss vs climo anytime soon are reduced somewhat though that's nowhere near a guarantee as temp. north of 80N is only one of the variables: