Tag Archives: Bering Sea

The 2018 Maximum Arctic Sea Ice Extent

According to the latest edition of the National Snow and Ice Data Center’s “Arctic Sea Ice News”

On March 17, 2018, Arctic sea ice likely reached its maximum extent for the year, at 14.48 million square kilometers (5.59 million square miles), the second lowest in the 39-year satellite record, falling just behind 2017. This year’s maximum extent is 1.16 million square kilometers (448,000 square miles) below the 1981 to 2010 average maximum of 15.64 million square kilometers (6.04 million square miles).

The four lowest seasonal maxima have all occurred during the last four years. The 2018 maximum is 60,000 square kilometers (23,200 square miles) above the record low maximum that occurred on March 7, 2017.

Here’s a close up view of recent maxima via the NSIDC’s Charctic interactive sea ice graph:

Charctic-20180323

Next let’s take a look at extent data from the Japanese National Institute of Polar Research, colloquially referred to as “JAXA extent”

VISHOP_Extent-20180323

In this case the maximum was 13.89 million square kilometers, also on March 17th.

Here too are the extent and area graphs based on Wipneus’ processing of the University of Hamburg’s AMSR2 based concentration data:

UH-Arctic-Extent-2018-03-23

UH-Arctic-Area-2018-03-23

They highlight the surge in Arctic sea ice area in the middle of March due to the sudden “cold snap”:

meanT_2018-03-24
Looking at the third Arctic dimension, here’s the latest SMOS thickness map from the University of Bremen:

SMOS-20180323

and here’s the latest CryoSat-2 thickness map:

CS2-thk_28-2018-03-21

They reveal large areas of relatively thin sea ice in the Okhotsk and Barents Seas where the ice can now be expected to melt as quickly as it formed. There is also remarkably little sea ice in the Bering Sea for the time of year:

UH-Bering-Extent-2018-03-23

The 2016 Arctic Winter Sea Ice Puzzle

Professor Judith Curry recently posed the following rhetorical question on her “Climate Etc.” blog:

Arctic sea ice extent has been anomalously low this winter. The greatest anomalies are in the European sector, specifically in the Barents Sea. To what extent are the anomalies associated with warm temperatures?

Which she answered as follows:

So, what might be causing this particular anomaly? Some possibilities are:

  • Gobal warming (January 2016 was warmest Jan on record, according to the surface temperature analyses

  • Multidecadal oscillations (e.g. stadium wave) predicts ice recovery to be occurring in the same region (European Arctic) where we see the sea ice decline).

  • Seasonal weather circulation patterns – this has been a year with with unusual weather patterns, with both low temperature and high temperature records being set.

As regular readers will already be aware we have been blogging about anomalously warm temperatures in the Arctic all year and so felt well qualified to contribute to the “debate”. What a job that turned out to be! Early on in the proceedings the anticipated pronouncement was made by one of Judith’s “denizens”. A link to a ludicrously inaccurate article on Watts Up With That accompanied by the following words of wisdom:

Other measures are high.

Which of course they aren’t! Instead of stating the bleedin’ obvious Professor Curry replied:

I spotted this, no idea what to make of it.

You would think she and her denizens would therefore have been pleased when I attempted to explain to her what to make of it, but you would have been mistaken. The icing on the ad hominem cake was the aforementioned Anthony Watts driving by to accuse me of all sorts of nefarious activities without providing a single shred of evidence and then running for the hills when invited to actually prove his ludicrous allegations.

Since the denizens of “Climate Etc.” aren’t particularly interested let’s take stock here instead shall we? After every Arctic area and extent metric under the sun sitting at “lowest *ever” levels for weeks a recent increase in coverage on the Pacific side of the Arctic has changed that. The most up to date example of that is the JAXA/ADS extent, which currently looks like this:

vishop_extent-20160228

The latest reading is the merest whisker above 2015’s record low maximum. However in other respects things are most certainly not comparable with 2015. See for example this concentration comparison from Andrew Slater of the NSIDC:

ice_con_delt_20160227

Much more ice on the Pacific periphery where it will all have disappeared by September, as opposed to much less ice on the Atlantic side, even well to the north of 80 degrees latitude where the sun still does not shine. Here’s a video revealing how the sea ice North of the Pacific Ocean has been reacting to the sequence of hurricane force storms that have been passing through the area over the past couple of months:

Now let’s take a look at “near real time” Arctic sea ice thickness as measured by the CryoSat 2 satellite:

CryoSat2_20160225

Notice the absence of any thick ice in the Beaufort and Chukchi Seas, an obvious difference from last year? Notice too the large area of thick ice that looks as though it’s heading towards the Fram strait exit from the Central Arctic. Here’s another video, this time of sea ice movement over on the Atlantic side of the Arctic Ocean:

Those dark areas between Svalbard and the North Pole are suddenly starting to look as though they represent reality rather than a mere “artifact”, although perhaps they are merely transient evidence of yet another Arctic “heat wave”?