Arctic Ice Mid April

 

BOday1042012to2018
Click on image to enlarge.

The most obvious Arctic ice feature this year has been the shrinkage in the Pacific basins, especially Bering Sea (on the right).  The image shows extents on day 104 from the decadal high in 2012 to 2018 (yesterday).  Bering has only 200k km2 mid April 2018 compared to 1100k km2 six years ago.  On the left, Okhotsk has gone through ups and downs, but 2018 is comparable to 2012.  there is a Siberian influence on Okhotsk, while It appears Bering is dominated by Northeast Pacific warming, whose effects are moderated in Okhotsk by Siberian conditions.

This is evident in the current nullschool simulation of wind patterns in the region:

https://earth.nullschool.net/#current/wind/surface/level/orthographic=-182.77,53.61,1130/loc=-167.641,51.083

On the European side, Barents continues to show more ice than in recent years. Ice in Barents Sea has retreated in recent days, but extent there is still above average and slightly larger than 2014,the iciest recent year.  As the graph shows 2017 came on late in Spring to surpass 2014 for awhile.

The graph below shows how Arctic extent over the last six weeks compared to the 11 year average and to some years of interest.

Note the average max on day 62 and 2018 max on day 74.  In recent weeks 2018 is matching 2017 and slightly higher than 2007. SII (NOAA) continues to show ~200k km2 less extent. The graph below shows that the deficit to average is entirely due to Bering and Okhotsk Seas, since removing those two basins eliminates the deficit to average.

The table below confirms that the core Arctic ice remains firmly in place.

Region 2018104 Day 104 
Average
2018-Ave. 2007104 2018-2017
 (0) Northern_Hemisphere 13956065 14373298 -417234 13862996 93068
 (1) Beaufort_Sea 1070445 1068880 1565 1058157 12288
 (2) Chukchi_Sea 962477 965131 -2654 960944 1532
 (3) East_Siberian_Sea 1087137 1085763 1374 1074001 13136
 (4) Laptev_Sea 897845 894331 3514 866524 31321
 (5) Kara_Sea 934919 925323 9596 912398 22521
 (6) Barents_Sea 708699 609715 98984 521344 187355
 (7) Greenland_Sea 575274 663379 -88104 691751 -116477
 (8) Baffin_Bay_Gulf_of_St._Lawrence 1340040 1352819 -12779 1222152 117888
 (9) Canadian_Archipelago 853109 852426 683 846282 6827
 (10) Hudson_Bay 1260022 1245760 14263 1212987 47035
 (11) Central_Arctic 3200334 3238761 -38426 3245148 -44813
 (12) Bering_Sea 189180 780469 -591289 645687 -456507
 (13) Baltic_Sea 68363 44683 23681 20075 48289
 (14) Sea_of_Okhotsk 805400 639794 165606 576913 228487

The overall deficit is~3%, entirely due to Bering Sea.  Okhotsk and Barents are above average, but not enough to offset lack of ice in Bering.

Drift ice in Okhotsk Sea at sunrise.

 

via Science Matters

https://ift.tt/2JLfi80

April 15, 2018 at 11:19AM

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

w

Connecting to %s

%d bloggers like this: