Meltponds and leads in the Arctic ice cap show evidence of refreezing

The daily ice extent minimums are behind us, and now the story is how fast will be this year’s recovery of ice compared to other years.

First the daily situation at the end of September:

September 30 day 273 results from MASIE. 2015 has overcome 2/3 of 2014 ice extent lead.

Since the annual minimum on day 262, 2015 recovery rate was 60k m2 per day compared to 41k per day in 2014.

2015 ice extent now trails 2014 by 6.1%, which is about 337k km2 difference.

Extent in BCE region is building ice now at 81% of last year. Largest recent increases were in Laptev 43k, Kara 33k, Beaufort 15k, CAA 23k, and most importantly, the Central Arctic is now 220k above its minimum 29 days ago.

The graph shows that a gap opened when 2015 ice dropped at the time of an Arctic cyclone late August.  The differential of almost 1M km2 has now been cut to 337k km2. and closing. 2015 ice extent was lower than 5M km2 for only 28 days.

2015 Recap:

The 30 days of September 2015 are in the books, so we now have the melt season conclusion beyond the daily minimums.

Sept. results for recent years from MASIE Plots   h/t to Andres Valencia

https://nsidc.org/data/masie/masie_plots.html

For most of the season, 2015 Arctic sea ice extent was tracking 2014. In fact the July average extent was slightly higher than 2014. Then weather intervened in the last week of August. A large and strong cyclone centered over Chukchi Sea began breaking up ice in the BCE Region and affecting CAA (Canadian Archipelago) and the Central Arctic.  In addition, most of the summer the Arctic Oscillation (AO) was in negative phase, meaning fewer clouds, more direct insolation and ice melting.  More discussion of these two factors is at the end of this post.

The effects of this storm are seen in the rapid increase in water extent ( 482k km2 in one week) so that August 31 2015 had less ice than did 2014 at minimum September 19. Water extent continued to grow, and then stabilized once the storm abated and the AO went from negative to neutral.  Now the ice is growing beyond the daily minimum.

Comparing MASIE and NOAA Ice Extents.

The table shows July 2015 was above 2014 but late August weather caused a drop in monthly averages.  The August average shows ice extent dropped ~2.7M km2 from July, compared to a 2014 loss of ~2.0M. That difference persisted until the minimum was reached. NOAA typically reports a lower extent than MASIE, a difference that averaged ~300k km2.  Then in one week MASIE dropped while NOAA plateaued, and until recently NOAA September extents were quite close to MASIE, some days showing a higher number.

With the September daily ice starting out lower than 2014 the monthly average ended up smaller.  The SIPN median forecasts for September (dated July and August) were 4.8M km2 and NOAA came in a 4.6M.

In any case, I am not alarmed over open water in the Arctic. Steadily increasing and above average September ice extents signify the coming of the next ice age, a genuine threat to human life and prosperity.  Fortunately, that is not the indication this year.

Current and Recent Weather in the Arctic

In addition to the storm, the negative AO has been conducive to accelerating ice melting by increased insolation.

September 30 Arctic Oscillation Forecast from AER:

Currently, the AO is neutral but is predicted in the short term to trend positive and peak at moderate to strong positive values this weekend (Figure 2). The positive AO trend is reflective of the below normal geopotential heights dominating the Arctic basin while positive geopotential heights dominate the mid-latitudes, especially the North Atlantic sector.   The AO value for this past July and August was the second lowest observed since 1950.

“The positive trend in the AO and the setting sun may have brought an early end to the Arctic sea ice melt season but not before sea ice extent achieved its fourth lowest value since observations began.  It is likely that the extremely low AO values observed in July and August are reflective of atmospheric conditions (sunny and warm) that were conducive to rapid sea ice melt.”

https://www.aer.com/science-research/climate-weather/arctic-oscillation

The Alaska Dispatch News reported August 27 on the storm effects at Barrow, Alaska:

“The service has issued a coastal flood warning for Barrow until Friday morning, along with a high surf advisory for the western part of the North Slope and a gale warning for much of the Beaufort and Chukchi Seas. Seas up to 14 feet were forecast for Thursday in the Chukchi. . .Thursday’s high waves and flooding are products of a large storm that’s being felt as far as Southcentral Alaska, where high winds are forecast, Metzger said. “It’s a pretty big low-pressure system that’s over the Arctic Ocean,” he said. ”

https://www.adn.com/article/20150827/high-winds-causing-big-waves-flooding-barrow

a quarter million square KM of arctic ice in the CAB, adjacent to the Beaufort and Chukchi. 20150829

This storm is reminiscent of the 2012 event that resulted in the lowest ice, greatest water extent this century. The high winds, waves and swells have several effects: Gales push ice floes, opening water between them and pushing them toward warmer waters; Ice pieces are churned and fractured increasing the melt rate; Wave action can flood ice packs or can cause compacting, further reducing extent.

Update October 4

Fooling Around

Dosbat has commented on my Arctic Ice posts: http://dosbat.blogspot.co.uk/2015/10/a-fool-by-any-other-name.html

He sees clearly and correctly that I am “playing the fool.” That is, I am not taking the conventional view of Arctic Sea Ice. We call someone “foolish” for not saying and seeing things the same as the rest of us.

It’s a long, respected tradition. Monarchs valued highly their fools because they would speak to the king of things contrary to what everyone, including the king believed to be true. King Canute himself played the fool to show his court the truth. And it was an innocent child who broke the silence over a king’s nakedness.

It’s a risky business, because you could be right or wrong.  Who’s fooling whom?

More foolery coming soon.

And from the “Open Mind”

Tamino (Grant Foster) recently posted a hit piece against my Arctic Ice Rebound article.
https://tamino.wordpress.com/2015/09/28/epidemic-of-denial/

I went there, to the  “Open Mind”  blog to clarify some misunderstandings, but for my few comments I was ridiculed and insulted.  So I disengaged.

Some commentators thought I should be ashamed of my last name.  So let me introduce them to my extended family:

That’s right, we had a starring role in the Oscar-winning movie, The Grand Budapest Hotel.

Meet the Lutzes:

They take very seriously insults against the family name, and as the movie shows, they can be quite determined and extreme in their retaliations.  Just saying.

But Seriously, What is the Problem?

Grant Foster and friends are committed to a warmer future and expect Arctic Ice extent to decline.  They are unhappy with me pointing out the lack of decline recently. So my post is off-message, and they are attacking the messenger.  Same old, same old.

Foster was considerate to write a longish post against my work, and he included a number of graphs that confirm one of my main points: not much is happening with the Arctic ice cap, despite the seasonal fluctuations.  Tamino found an issue as an excuse to dismiss my entire analysis (and me and my blog along with it). I had included an annual average for 2015 which covers only the first 3/4 of this year.  I mentioned this figure would not be known for certain until year end.  Foster cleverly figured out that in the days (and weeks) ahead the figure will go down.  But come November and December it will rise again.  Not even Tamino knows what it will be until December 31.  It depends on the future rate of seasonal ice recovery.

My graph included only historical observations from MASIE, not projections or estimations.  The proper scientific thing would be to wait for the year to end.  But climate science, as we all know, is not only science, it is a movement and a media blitz ahead of a major (last ditch?) conference in Paris.  The story of Arctic ice will be written and sold to the public long before the year’s observations are complete.

Another Way to Get Perspective

I prefer a calendar year frame for Arctic Ice not only for ease of understanding, but also because the break point in annual cycle is neutral, occurring mid-way between minimum and maximum.  In order to avoid using a provisional value, but still incorporate all the data, I have done an analysis taking 12 month averages from the end of September backwards; in effect combining the last quarter of the previous year with 3/4 of the current year, and so forth for preceding years.  For the first year, 2006, I present the average as reported; that is, rather than estimating the last quarter of 2005, I have included the actual 2006 data.

The graph shows the annual averages Oct 1 through Sept. 30.  On this basis, the variability of ice extent is reduced, and  2014 has the highest extent, with 2015 in second place.  The decadal  trend is still an increasing one, though at a lower rate than when the calendar year is used.  The basic findings are the same.  This analysis substitutes the 2014 last quarter recovery rate for the actual  next 3 months yet to be observed.  Since the 2015 maximum was unusually low, the actual next quarter results may go higher.  We shall have to wait and see.

Note: I use the term “trend” in its dictionary definition: “the general direction of changes or developments” (Cambridge Dictionary).  In any time series, there is an overall trend or direction, and within are usually periods identifiable by change points where short-term trends deviate from the overall.  Evidence is mounting that 2007 may be such a change point.

Some say that trend can only be mentioned with the meaning of expected values, and the dataset is not long enough to say this surely. This is the same gambit made when surface temperatures stopped rising.  Whether it is the temperature or the ice plateau, the advice is the same: “You should ignore what is happening before your eyes because it is not real, statistically speaking, unless it continues for another decade or so.  Meanwhile let’s wrap up the emissions treaty.”

Summary

Those hoping for an Arctic ice collapse this year are disappointed.  Everything was in their favor: a low March maximum, the Blob melting out Bering Sea early, a negative AO (Arctic Oscillation) with higher insolation most of the summer, and a major cyclone last August when ice edges are most fragile. Despite all that working against the ice, the extent was lower than 5M km2 ( 2014 minimum) for a period of only 28 days. Furthermore, the 12 month averages show extent slightly rising over the last 10 years, with 2015 second only to 2014.

Note on datasets

MASIE is not the only dataset to show this lull in Arctic ice decline. It is also obvious in Foster’s final graph.  Some were upset that I used the MASIE data, despite NSIDC cautions against it.  For the record, the NSIDC Background cites as support a study by Partington et al (2003).  Reading that study, one finds that the authors preferred the MASIE data and said this:
“This analysis has been based on ice chart data rather than the more commonly analyzed passive microwave derived ice concentrations. Differences between the NIC ice chart sea ice record and the passive microwave sea ice record are highly significant despite the fact that the NIC charts are semi-dependent on the passive microwave data, and it is worth noting these differences. . .In summer, the difference between the two sources of data rises to a maximum of 23% peaking in early August, equivalent to ice coverage the size of Greenland.” (my bold)  For clarity: the ice chart data show higher extents than passive microwave data.

http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1058&context=usdeptcommercepub

In any case, NSIDC’s last word was this:  “In June 2014, we decided to make the MASIE product available back to 2006. This was done in response to user requests, and because the IMS product output, upon which MASIE is based, appeared to be reasonably consistent.”  And thus, the data appeared this September.

Conclusion

Arctic ice extent is no longer declining and a slight increase was observed in the last decade.  People have a right to know about this as a context to evaluate claims that are coming.

Nothing alarming is happening to Arctic ice.