ASI 2015 update 6: one more high

During the melting season I'm writing (bi-)weekly updates on the current situation with regards to Arctic sea ice (ASI). Central to these updates are the daily Cryosphere Today sea ice area (SIA) and IJIS sea ice extent (SIE) numbers, which I compare to data from the 2005-2014 period (NSIDC has a good explanation of sea ice extent and area in their FAQ). I also look at other things like regional sea ice area, compactness, temperature and weather forecasts, anything of particular interest.

The animation on the right consists of NSIDC
sea ice concentration maps, one for each ASI update.

Check out the Arctic Sea Ice Graphs website (ASIG)
for daily updated graphs, maps, live webcam images and
the Arctic Sea Ice Forum (ASIF) for detailed discussions.

August 19th 2015

We are now entering the final weeks of the 2015 melting season. A relatively cold and cloudy start (not as cold and cloudy as the two previous rebound years) was compensated by a July that was ideal for melting. A continuous bombardment of heat and sunshine for weeks on end has caused some late melting momentum which is now keeping sea ice extent and area numbers dropping relatively evenly, despite a switch in weather conditions since the beginning of the month (see ASI 2015 update 5: late momentum).

As expected, the 2015 trend line on most graphs is hovering between top 3 years 2012, 2007 and 2011, and rebound years 2013 and 2014. It's difficult to tell how low things will end up. Melting momentum is one thing, but at this stage of the melting season weather conditions have the last word. It's compaction rather than melting that determines the final shape of the ice pack, and compaction depends on which way the winds are blowing, which in turn depend on the constellation of cyclones and anti-cyclones, or high pressure areas. See this blog post from an eternity ago, 2010, that explains how it works.

And now for the details...

Sea ice area (SIA)

Here's the latest Cryosphere Today SIA chart, to which I've added preliminary data as calculated by Wipneus:

In the past two days the 2015 trend line has dipped below the daily minimums of rebound years 2013 and 2014. With 3 weeks in the melting season left to go I think it's safe to say that the rebound in the CT SIA data set has essentially been eliminated. The only question now is whether 2015 can still end up 2nd or 3rd. It's almost impossible to predict, as all the minimums are huddled close together. It might just as well come in 4th or 5th. Bottom line is it'll be low yet again.

Sea ice extent (SIE)

With sea ice extent it's a slightly different story, as can be seen on this graph based on data from the Japanese Arctic Data archive System website:

The trend lines are somewhat closer to each other, showing smaller fluctuations, and here the 2015 trend line will have to drop another 500K km2 to get below the 2013 and 2014 minimums. Some seriously favourable weather conditions will be needed for 2015 to make the top 3.

Cryosphere Today area per IJIS extent (CAPIE)

But the potential is there, if the CAPIE or compactness graph is to be believed:

The CAPIE percentage is still among the lowest in the 2006-2015 period, lower than 2012 even, and this is in large part because of the heavy dispersal of the ice pack on the Pacific side of the Arctic, with a massive detachment of multi-year ice (I'll have more on that in a couple of days when all of the detached ice has melted out):

If winds turn and push all that dispersed ice together towards the Canadian Archipelago, area and especially extent may go quite a bit lower. This is what made 2007 the record year it was, as winds blowing in the right direction caused heavy compaction in the final weeks of the melting season. Years like 2010 and 2013 didn't fulfil their potential because cyclones kept the ice pack dispersed until freezing temperatures started the process of ice re-growth and all the open water between floes iced over.

Regional SIE and SIA

In anticipation of that upcoming blog post on the detachment of an 'arm' of ice in the Beaufort Sea, its disappearance and the consequences for multi-year ratios, I can already show you the difference compared to two weeks ago, thanks to this fantastic map produced by commenter Wipneus who makes his own sea ice concentration maps using the highest resolution AMSR-2 data (3.125 km grid) provided by the University of Hamburg:

Wipneus also sent me this two-week delta map showing changes in the Canadian Arctic Archipelago where the Northwest Passage main route is close to opening (ships are already taking on the southern route through Bellot Strait that Roald Amundsen took in his legendary 1903-1906 traversing of the NWP):

Whether the main route opens up completely mostly seems to hinge on the question whether ice will clog up the western entrance at M'Clure Strait or not. My guess is it will be open all the way, from east to west, and yet again we'll see both the Northern Sea Route and the Northwest Passage open at the same time. I guess that the people who like to dig through archives to show that current events in the Arctic have happened before, would've have flaunted some decades old newspaper article announcing the fact that the Arctic was circumnavigable, if it existed. So maybe, perhaps, possibly this is unprecedented and a sign that humans are rapidly changing the way the planet looks and its systems function?

But to return to the update, here are regional sea ice extent graphs of the Central Arctic Basin and Eastern Siberia Sea, the two most important regions left:

The East Siberian Sea was rapidly getting cleared of ice, but after weather conditions flipped and ice is being pushed outward again, the trend line has made a spectacular Sandy-like bend. Still, there is some potential left here, as there is in the Laptev Sea,on top of a small amount of piggy bank ice left in Baffin and Hudson bay. See Wipneus' regional graph for all the details.

Weather conditions

Let's have a look at that shift in weather conditions, with the help of this animation of Danish Meteorological Institute SLP images:

What we see here, is what I like to call the neither-fish-nor-flesh set-up (young people might call it the meh set-up). There's no intense high pressure to deepen the ice's sunburn, but there aren't any mighty cyclones either to stir up the ice, bring up warmer water and flip ice floes (their bottoms are usually much darker because of algae). There have been a few short-lived cyclones in the past 2-3 weeks, but that's it, little movement, little compaction, little transport. The fact that trend lines have continued to drop instead of stalling (like happened in 2013 and 2014) is a sign that melting momentum has kept things going.

The animation gets interesting towards the end, with a large high pressure area showing up on the Siberian side of the Arctic, leaning towards the centre. Let's see what the ECMWF weather forecast model has in store for the coming 6 days (click for a larger version, and go to the ASIG Forecasts page for daily forecasts):

The high pressure area stays in place, stays intense at 1030 hPa and stays big. A few weeks ago this would have totally destroyed the ice on the Siberian side of the Arctic, because that's what clear skies do for first year ice. But in this phase the Sun is getting lower and clear skies also mean a lot of outgoing radiation, which leads to lower temperatures (see temp animation below). At the same time the combination of this high pressure area with low pressure on the American side of the Arctic causes winds to further disperse the ice pack.

The overall effect of this set-up will probably make it more difficult for this melting season to end up in the top 3, but might also cause some late havoc on the Atlantic side of the Arctic, where the first-year ice has seen little action this year. And of course it will push some more multi-year ice on the Pacific side towards warmer waters.

When it comes to air temperatures, the DMI 80N temperature graph makes clear that things will soon start to get colder (in the Central Arctic north of 80° first), but temperatures have been relatively high all summer with the trend line around and even above the average:

When the trend line starts to make high jumps or stays way above the average, we'll know that a colder atmosphere is forcing the heat out of the sea surface so that it can freeze over. It's a bit early for that, although freezing temperatures are starting to show up as we speak. Temperature anomalies don't show this well, and so I return to actual temperature maps for the coming 7 days as forecast by the GFS model, provided by Climate Reanalyzer:

It will take a while for these freezing temperatures to spread out, but the battle with melting momentum has begun. And one melting momentum factor is sea surface temperatures:

Plenty of heat on the Atlantic side of the Arctic that is going to get pushed along that front of homogeneous first-year ice, but less heat on the Pacific side to receive the floes that will be pushed towards it. The heat distribution is similar to 2013 around this time, but both 2012 and 2014 has most of their heat on the Pacific side of the Arctic (albeit 6 and 4 days later respectively):

Conclusion

Melting momentum (simply put, a combination of thin ice and warm sea surface temperatures) may keep that steady decrease going and there definitely is a lot of compaction potential, but it's mostly all down to winds now. Regardless of how it all plays out, 2015 will be another low year, with both passages possibly opening up again, and volume and multi-year ice getting reduced again.

More will be known when the next ASI update at the start of September is published. To close off, I can simply repeat this paragraph from the previous ASI update:

The rebound (or 'recovery', as some called it prematurely) is in danger of getting wiped out, which brings us back to square -10, meaning that Arctic sea ice loss is still progressing much too fast.

Enjoy the Arctic sea ice, it's the only Arctic sea ice you've got.

Comments

[TenneyNaumer]

The AMSR2 graphic cannot be correct in the region at the head of the Nares Strait, see here:

https://earthdata.nasa.gov/labs/worldview/?p=arctic&l=MODIS_Aqua_CorrectedReflectance_TrueColor,MODIS_Aqua_CorrectedReflectance_Bands721(hidden),MODIS_Terra_CorrectedReflectance_TrueColor(hidden),MODIS_Terra_CorrectedReflectance_Bands367(hidden),MODIS_Terra_CorrectedReflectance_Bands721(hidden),Graticule,Coastlines&t=2015-08-17&v=-377271.916414413,-895588.6609942755,-3511.916414413048,-691812.6609942755

[TenneyNaumer]

And, slightly off topic, check out Greenland's west coast:

http://manati.star.nesdis.noaa.gov/ascat_images/ice_image/msfa-NHe-a-2015230.sir.gif

[Neven]

The AMSR2 graphic cannot be correct in the region at the head of the Nares Strait, see here:

Which AMSR2 graphic? The Uni Bremen SIC map? Looks pretty accurate to me, keeping in mind that it will never be perfect.

[TenneyNaumer]

Concentration at the head of Nares Strait on the 18th was pitiful. SIC shows it in its heaviest color. Check the first link I posted. You can see that we have never had so little ice there.

[Kris]

TenneyNaumer wrote:

You can see that we have never had so little ice there.

.

Never!? We already have had severall years the Nares Strait was enterly open in the beginning of August. And by the way, do you realize the ice shelves blocking Nares Strait now are 10 @ 20 km across? No, Nares Strait won't become free this year.

[John Christensen]

Thank you for a great update Neven, I am in full agreement with status assessment and conclusion.

Regarding the forecast for high-pressure: After the next 3-5 days of relatively high-pressure, NOAA has forecasted a deepening of the high-pressure (negative AO index):

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/ao_index_ensm.shtml

At this late stage of the melting season, this should be ideal in reducing winds (reduce ice/water mixing), keep the ice from compacting and allow more heat to escape.
We will see how far this goes as to slow down melting in the coming couple of weeks - interesting!

[John Christensen]

One note on the meaning of the DMI 80N temperature in the main melting season (Approx. days 165-230):

It seems that the 80N temperature is comprised of two main factors:

1)Actual heat transported into the central Arctic area, plus heat created in situ by radiation
2) Energy exchange between water and air in open water areas

Because we now have much larger areas of open water in the 80N area compared to prior decades, the energy exchange between water and air seems to reverse the overall temperature signal.

Let's consider 1967:
The Arctic region was dominated by low pressure areas in May, June, and July, but still the 80N temperature on multiple occasions was above the long-term average, which is opposite to what we have seen in 2013 and 2014 low-pressure summer months.

Compare with 2009:
Both June and July saw strong high-pressure areas across the Arctic, but the 80N temp stayed significantly below the long-term average for most of the main melting season.

I would speculate that the reason why the 80N temp in 1967 was high, was that the ice cover in the 80N area was complete/near complete, allowing very little energy/cold from the water to be exchanged with the air.

In 2009, on the other hand, the 80N temp stayed low. This was probably not because of lack of heat energy created above water level, but because the broken ice pack allowed a high level of cold energy from the water to be exchanged with the air.

The 80N temps in the main melting seasons of 2012, 2013, and 2014 stayed low for the same reason: Very broken and scattered ice packs in the high north allowed lots of cold energy to be released to the air.

In 2015, however, the ice pack in the 80N area has had less cracks and fewer areas of open water, resulting in the 80N temp again being able to spike above the long-term average, simply because the water/air energy exchange at least in this most northerly area has been reduced compared to prior years.

[navegante]

Nice.

Out of curiosity, what is sandy-like?

[EthonRaptor]

Navegante: Hurricane Sandy took a sharp left turn towards NY/NJ.

FWIW, Eli has always thought that the amount of ice coverage outside of 80 N is a good indicator of the state of the ice.

[Philip]

MASIE dropped over 360,000km2 today the second time this month that there has been a drop of over 300,000km2. we live in interesting times.

[Neven]

Navegante: Hurricane Sandy took a sharp left turn towards NY/NJ.

That's exactly it. I wrote about it at the time, a couple of days before the storm made that crazy 90° turn.

[TenneyNaumer]

I am not referring to the Nares Strait itself but north of it. The ice is just in a deplorable state. Did you notice the big melt off of such thin ice? Look today off Ellesmere -- this is by far the worst condition the sea ice has ever been in that region:

https://earthdata.nasa.gov/labs/worldview/?p=arctic&l=MODIS_Aqua_CorrectedReflectance_TrueColor(hidden),MODIS_Terra_CorrectedReflectance_TrueColor,Reference_Labels(hidden),Reference_Features(hidden),Coastlines(hidden)&t=2015-08-20&v=-944499.7323994946,-1163313.1624603223,550540.2676005054,-348209.16246032226

[NeilT]

I notice that the press is full of the July temps being comprehensively higher than 98, finally putting to bed the whole denialist "pause" rubbish.

Given that this is also not a huge outlier year as 98 was, we should see these temps as normal by 2020.

It would be interesting to compare the 98 melt season with the 2015 melt season. Just to rub in what is going on and crush any last idiocy of a pause...

[Remko Kampen]

Better not bet on that, NeilT. Climate revisionism is already preparing for another 'hiatus' because of this year. And, of course, 'Ice Age cometh', the latter meme will revive hugely by November.
And it still works perfectly. This year some more governments got couped by fossil fuel industry. Spain, who actually punishes solar panel use. Holland, where percentage renebables is less than half the EU average and dropped second year in a row. Canada, burning books. Ireland, who just got a secretary of energy/climate who works for Shell and is actively killing renewable initiatives there, subsidies down the drain. Australia whose subsidies to Abbott of Big Coal amount to almost 2% of Australian GDP this year. Forget it - gloat when Florida gets removed from the map thru SLR plus hurricane, because that kind of thing is the planet's only chance now.

[Remko Kampen]

Meantime's climate revisionist's strategies focus on 'the numbers are fudged' or, well, El Niño 'so of course it's a hot year' never mind past Niño years that weren't that hot - they conceal trends which looks stupid to us but is simply smart because they are believed.

[Kris]

NeilT wrote:

It would be interesting to compare the 98 melt season with the 2015 melt season.

We even can do better and include the “accident-years” [as deniers use to call it] into a comparision. The “accident-years” being 2002, 2007 and 2012. Note there seems to be a 5 years space between each “accident”.

Just click onto this link: NSIDC semptember comparison. 2005 which was a minimum record year too is included too.

To compare other months, just change the month selection and click onto refresh. And of course, you can include other years too if you would like it to do so.

[Hans Gunnstaddar]

"I notice that the press is full of the July temps being comprehensively higher than 98, finally putting to bed the whole denialist "pause" rubbish."

Until 2016 is 'cooler' than 2015 (because warming is uneven year to year, yet spiraling higher), then they will claim the planet is getting cooler just as they did after 1998.

For whatever reason, whether it is denial or just plain obstinate, unless the temps are consistently increasing in a 'linear' fashion over a long period of time in which each successive year is obviously greater than the previous year and there are no deviations to that rule, denialists will continue to remain in that state.

That same situation is true of Arctic ice. Even though September 2012 hit a shockingly low all time record minimum, once 2013 & 2014 rebounded somewhat higher, the denialists became convinced it can all be chalked up to natural fluctuations, missing completely the overall undulating downward spiraling trend.

It's also possible that being in denial is simply no different than not caring. A lot of people (myself not included) just don't care about anything except themselves, so if they think it won't unduly affect them negatively within their lifetime, they simply don't care. Otherwise why would they fight the idea of global warming so hard? They fight it out of a fear their lives will have to change if there is a threshold acceptance of global warming, and instead of having a giant internal combustion truck gurgling and popping down the street they have to switch to a silent economy electric vehicle charged by PV panels. They want hardwood floors from illegally cut wood out of South America. They want fuel from any source including arctic oil.

[Bill Fothergill]

NeilT wrote:

It would be interesting to compare the 98 melt season with the 2015 melt season.

Kris supplied a very interesting link to NSIDC's BIST tool. However, if anyone is unfamiliar with this, it might be easier to start with this unparameterised link...
http://nsidc.org/cgi-bin/bist/bist.pl

(Or simply use the Search function on the NSIDC website with the string "Browse Image Spreadsheet Tool", and pick up BIST from the obvious result.)

When it is initialised with certain preset parameters, it can be difficult to get BIST to access all the functionality contained therein.

For example Neil, if you select the "Extent & Concentration Trends" option, then chose 2 columns and 12 rows - with one column set to Conc and the other to Extent, the 12 rows will populate automatically for each of the months.

Alternately, for a possibly far better comparison, use the NSIDC's "Charctic" tool to compare Extent values. If you deselect everything except 1998 and 2015, the comparison is stark in the extreme.
http://nsidc.org/arcticseaicenews/charctic-interactive-sea-ice-graph/

One can repeat this for SIA using CT's interactive visual tool...
http://arctic.atmos.uiuc.edu/cryosphere/arctic.sea.ice.interactive.html

It's a bit more clunky on CT, as I've yet to find a "Select All or Deselect All", and therefore each year has to be turned on/off individually.

Hope that helps

[Tanada1945]

For some reason I can never remember if Positive or Negative AO is the one that encourages more ice to flow out through the Fram Strait. Thus I don't know if the building negative AO value will increase the transport rate or slow the transport rate down to a lower value.

Right now the current 2015 CIA reading from the Cryosphere Today web page is below the seasonal minimums for all years before 2007 as well as 2009, 2013 and 2014. The next records to be passed will be 2010 with 3,072,130 km^2 and 2008 with 3,003,560 km^2 I think it is highly probable 2015 will pass both of them in the next 20 days but I am not a climate scientist, just as interested observer trying to figure things out with the data available for free online.

[George Phillies]

While we are focused on the Arctic, it is perhaps worth a mention that the Antarctic, on the Bremen graphs, is not doing a very good job of freezing this year. Of course, it has a while to go, but on current trends may be another spike in the denialist coffin.

[Bill Fothergill]

@ George P

Regarding the White Continent, CT SIA for Day 230 is nearly 1.5 million sq kms down on the equivalent date in 2014. When ranked, that puts Day 230 in the middle of the lower quartile.

Note however, that things can change very quickly given the circumpolar circulations down there. Between Days 239-261 last year, there was an upward hike of just over 1.5 million sq kms. Timed so close to the equinox, that was unlikely to be genuine freezing - more a case of spreading due to wind/wave action.

[AbbottisGone]

Regarding the comparison of things: I've found 2005 to be a possible tipping point. Does anyone else agree?

[AbbottisGone]

http://nsidc.org/cgi-bin/bist/bist.pl?annot=1&legend=1&scale=75&tab_cols=2&tab_rows=2&config=seaice_extent_trends&submit=Refresh&hemis0=N&img0=trnd&hemis1=N&img1=plot&mo0=06&year0=2015&mo1=07&year1=2015
Interesting, cheers Bill. August and September trends were obviously worse but I felt like looking at June and July so ... I guess that itch has now been scratched ~#^>'///,<

[DavidR]

NeilT wrote
"It would be interesting to compare the 98 melt season with the 2015 melt season. Just to rub in what is going on and crush any last idiocy of a pause..."

2015 and 1998 are NOT comparable. The El Nino we associate with 1998 started in 1997, setting a global temperature record, and then finished in April 1998, setting another record more than 0.15 degrees hotter than 1997. We never saw another year cooler than the previous record set in 1995.

If this El Nino finishes in April 2016 as expected we should expect to see a new temperature record in 2016. If that occurs it is unlikely that we will see another year as cool as 2014 in our lifetimes.

[DavidR]

Bill Fothergill wrote:
"Alternately, for a possibly far better comparison, use the NSIDC's "Charctic" tool to compare Extent values. If you deselect everything except 1998 and 2015, the comparison is stark in the extreme.
http://nsidc.org/arcticseaicenews/charctic-interactive-sea-ice-graph/"

If you compare 1983/1984 or 1998/1999 you can see what happens to the arctic the year AFTER the El Nino finishes (2017) and that should REALLY concern us.

[AbbottisGone]

..DavidR,

You are saying the year after an el nino the sea-ice extent minimum in the arctic drops?!!?

You are perhaps also saying the maximum drops aswell!??!

(I'm just asking for the purposes of clarity!)

[John Christensen]

"a massive detachment of multi-year ice (I'll have more on that in a couple of days when all of the detached ice has melted out)"

The fate of this MYI detachment will probably be the cliffhanger exciting question for the end of this melting season.
I agreed back on Aug. 20 that this should melt out, but with the lowering of the air temps, the forecast, and the limited heat energy remaining in the nearby waters, I am no longer sure this detachment will be parting with us this year.

[John Christensen]

DavidR,

Great observation: I had never reviewed the year after a larger El Nino and so had not spotted this relationship.

Looking at 1983 (El Nino ends) and 1984, PIOMAS data shows that in 1984 after reaching nearly the same max. volume as the year before, the volume declined faster from mid-March to end-June compared to 1983, and freezing was also reduced in late-Sep/Oct. of 1984 compared to 1983.

[DavidR]

AbbottisGone,
The maximums are low but not necessarily records at the start of the year.

The 82/83 El Nino ended in Apr 1983 and SIE extent dropped 800K km^2 to a record low in 1984.

The 97/98 El Nino ended in Apr 1998 and SIE droppped over 600K km^2 to a record low in 1999.

This El Nino is predicted to end in Apr 2016, you can draw your own conclusions about 2017 but my even money bet says 'Record Low Year'

[NeilT]

Thanks everyone for the suggestions. I changed jobs Fri/Mon and had a long weekend of travel and home stuff.

Still finding time to sort stuff out.

[AbbottisGone]

Interesting, thankyou DavidR.

[Kris]

Noteworthy, Baffin Island has regained his full status of island now (time being) as can be deduced from today"s Uni-Bremen map.
At the other end of the archipelago, shelves on the loose are more and more blocking the M'Clure Strait. Well, this year there is a record amount of shelves on the loose, isn't it?

[Philip]

with the significant uptick on CT area it suggests a curtailed melting season. similar significant disruptions to the curve have happened in the past in 1983 1994 and 2004 when with the brakes on the remainder of the final melt was between 200,000 and 500,000 km2. I therefore predict that the final figure will be between 3.05 and 3.4 million km2. a lower final figure now looks unlikely to me unless we get another significant weather event to disrupt the situation.