June Arctic Ice Returns to Mean

 

Arctic2021159

A previous post reported that Arctic Sea Ice has persisted this year despite a wavy Polar Vortex this spring, bringing cold down to mid-latitudes, and warming air into Arctic regions.  Now in June, after tracking in deficit the sea ice extent is matching the 14-year average on day 159.  Note that SII (Sea Ice Index) since mid-May has been showing 200 to 400k km2 more ice than MASIE, and currently the two datasets have converged on a value of ~11.25 M km2.

Note that on the 14-year average, during this period ~1.7M km2 of ice extent is lost, which 2021 is matching, as did 2007.  Both 2020 and 2019 were much lower than average at this date, by ~600k and ~700k respectively.  

Why is this important?  All the claims of global climate emergency depend on dangerously higher temperatures, lower sea ice, and rising sea levels.  The lack of additional warming is documented in a post Adios, Global Warming

The lack of acceleration in sea levels along coastlines has been discussed also.  See USCS Warnings of Coastal Floodings

Also, a longer term perspective is informative:

post-glacial_sea_level
The table below shows the distribution of Sea Ice across the Arctic Regions, on average, this year and 2007.

Region 2021159 Day 159 Average 2021-Ave. 2007159 2021-2007
 (0) Northern_Hemisphere 11240999 11259536  -18538  11316498 -75500 
 (1) Beaufort_Sea 1019264 964689  54575  1000434 18830 
 (2) Chukchi_Sea 849650 820007  29642  828275 21375 
 (3) East_Siberian_Sea 1018939 1060847  -41907  1065467 -46528 
 (4) Laptev_Sea 719152 797804  -78652  750975 -31824 
 (5) Kara_Sea 786077 768820  17257  805583 -19506 
 (6) Barents_Sea 253238 260182  -6944  312729 -59491 
 (7) Greenland_Sea 664297 581528  82769  579724 84573 
 (8) Baffin_Bay_Gulf_of_St._Lawrence 755645 803058  -47412  811860 -56215 
 (9) Canadian_Archipelago 802846 802905  -60  783908 18938 
 (10) Hudson_Bay 1022997 1058859  -35862  1027039 -4042 
 (11) Central_Arctic 3233401 3215315  18085  3235047 -1646 
 (12) Bering_Sea 59415 70145  -10729  62751 -3336 
 (13) Baltic_Sea 0 8 -8  0
 (14) Sea_of_Okhotsk 54471 53989  482  51031 3440 

The main deficits are in Laptev and East Siberian Seas, Baffin and Hudson Bays, offset by surpluses in Beaufort, Chukchi and Greenland Seas.

 

Ordinary Arctic Ice Extents in May

Arctic2021151

A previous post reported that Arctic Sea Ice has persisted this year despite a wavy Polar Vortex this spring, bringing cold down to mid-latitudes, and warming air into Arctic regions.  Now in May, the sea ice extent matched the 14-year average on day 144, tracking alongside until month end.  Surprisingly  SII (Sea Ice Index) is showing ~400k km2 more ice, which is also ~70k km2 higher than the 14-year average for SII on day 151 (not shown in chart).

Note that on the 14-year average, May loses ~2M km2 of ice extent, which 2021 matched, as did 2007.  Both 2020 and 2019 finished lower than average, by 300k and 400k respectively.  In contrast SII shows a May loss of only 1.3M km2.

Why is this important?  All the claims of global climate emergency depend on dangerously higher temperatures, lower sea ice, and rising sea levels.  The lack of additional warming is documented in a post Adios, Global Warming

The lack of acceleration in sea levels along coastlines has been discussed also.  See USCS Warnings of Coastal Floodings

Also, a longer term perspective is informative:

post-glacial_sea_level
The table below shows the distribution of Sea Ice across the Arctic Regions, on average, this year and 2007.

Region 2021151 Day 151 Average 2021-Ave. 2007151 2021-2007
 (0) Northern_Hemisphere 11605537 11733260  -127723  11846659 -241122 
 (1) Beaufort_Sea 1034779 992955  41825  1059461 -24682 
 (2) Chukchi_Sea 900868 861978  38891  894617 6251 
 (3) East_Siberian_Sea 1051959 1065828  -13869  1069198 -17239 
 (4) Laptev_Sea 738294 831217  -92923  754651 -16357 
 (5) Kara_Sea 824068 831440  -7373  895678 -71610 
 (6) Barents_Sea 325745 322981  2765  323801 1944 
 (7) Greenland_Sea 615174 567365  47810  591919 23255 
 (8) Baffin_Bay_Gulf_of_St._Lawrence 812548 908759  -96211  934257 -121709 
 (9) Canadian_Archipelago 811040 811378  -338  818055 -7015 
 (10) Hudson_Bay 1084892 1098368  -13476  1077744 7148 
 (11) Central_Arctic 3232324 3219180  13144  3230109 2215 
 (12) Bering_Sea 89124 122512  -33388  112353 -23228 
 (13) Baltic_Sea 0 161 -161  0
 (14) Sea_of_Okhotsk 83572 97612  -14040  83076 495 

The overall deficit to average happened yesterday, being an extent 1% lower, and two days earlier than average.  The largest deficits to average are in Baffin Bay and Laptev Sea, along with Bering and Okhotsk.  These are partly offset by surpluses elsewhere, mostly in Beaufort, Chukchi, and Greenland Seas.

 

 

May 24, 2021 Arctic Ice Matches Average

Arctic2021144

A previous post reported that Arctic Sea Ice has persisted this year despite a wavy Polar Vortex this spring, bringing cold down to mid-latitudes, and warming air into Arctic regions.  Now in May, the sea ice extent matches the 14-year average.  In the chart above, MASIE has caught up to its average, while SII (Sea Ice Index) is showing 300k km2 more ice.  This is also 200k km2 higher than the 14-year average for SII on day 144 (not shown in chart).

Why is this important?  All the claims of global climate emergency depend on dangerously higher temperatures, lower sea ice, and rising sea levels.  The lack of additional warming is documented in a post Adios, Global Warming

The lack of acceleration in sea levels along coastlines has been discussed also.  See USCS Warnings of Coastal Floodings

Also, a longer term perspective is informative:

post-glacial_sea_level
The table below shows the distribution of Sea Ice across the Arctic Regions, on average, this year and 2007.

Region 2021144 Day 144 Average 2021-Ave. 2007144 2021-2007
 (0) Northern_Hemisphere 12146819 12145771  1048  12035185 111634 
 (1) Beaufort_Sea 1014946 1014623  323  1063324 -48378 
 (2) Chukchi_Sea 926443 884593  41850  925212 1232 
 (3) East_Siberian_Sea 1074468 1068410  6057  1061115 13353 
 (4) Laptev_Sea 847289 862328  -15040  797581 49708 
 (5) Kara_Sea 850992 857488  -6495  898743 -47750 
 (6) Barents_Sea 414971 371726  43245  302721 112250 
 (7) Greenland_Sea 621173 588159  33015  573583 47591 
 (8) Baffin_Bay_Gulf_of_St._Lawrence 861138 985037  -123899  962331 -101193 
 (9) Canadian_Archipelago 836025 824730  11295  828387 7638 
 (10) Hudson_Bay 1109942 1135136  -25194  1091181 18761 
 (11) Central_Arctic 3241735 3223613  18121  3231990 9744 
 (12) Bering_Sea 212840 196725  16115  190680 22160 
 (13) Baltic_Sea 0 1039 -1039  619 -619 
 (14) Sea_of_Okhotsk 133703 130236  3467  105796 27907 

The largest deficit to average is in Baffin Bay, with Laptev and Hudson Bay also starting to melt.  These are offset by surpluses elsewhere, mostly in Chukchi, Barents, and Greenland Sea.

 

 

Mid May 2021 Persistent Arctic Ice

ArcDay135 2007 to 2021

 

Typically in climate observations, averages are referenced without paying attention to the high degree of component variability from year to year, and over longer time periods.  Mid May is when the Spring melt is well underway, but with the Arctic core still frozen solid.  Yet the animation above shows on day 135 over the last 15 years, there are considerable differences as to how much ice is in which regions. 

On the bottom left is Bering Sea which had ice extents on this day ranging from a high of 682k km2 (2012) to a low of 38k km2 (2018).  The day 135 average for Bering is 293k km2, but with a standard deviation of 192k (65%).  Okhotsk center left is the next most variable, from 290k (2012) to 99k (2019), averaging 188k with std. deviation of 63K (33%).  Barents Sea center top has a large variability from 568k km2 (2009) to 223k (2012), averaging 422k km2 +/- 111 k km2.  Other Arctic regions vary little on this day from year to year.  For example, Hudson Bay is close to 1.2M km2 every year on day 135.

The effect on NH total ice extents is presented in the graph below for the period mid April to mid May, comparing the 14-year average with 2021 MASIE and SII, and some other years of interest.

Arctic2021135

Note on average this period shows an ice loss of 1.5M km2.  MASIE 2021 is about 200k km2 below average, 1.6% down, or having the same total extent 3 days ahead of average.  Interestingly, SII shows about 200k higher, matching the MASIE average for day 135.

The table below shows the distribution of sea ice across the Arctic regions.

Region 2021135 Day 135 Average 2021-Ave. 2007135 2021-2007
 (0) Northern_Hemisphere 12490666 12692542  -201876  12431928 58738 
 (1) Beaufort_Sea 1058904 1044067  14837  1057649 1255 
 (2) Chukchi_Sea 926504 921289  5215  953491 -26987 
 (3) East_Siberian_Sea 1083562 1081242  2320  1075314 8248 
 (4) Laptev_Sea 852338 881285  -28948  828738 23600 
 (5) Kara_Sea 858111 882730  -24619  876053 -17942 
 (6) Barents_Sea 396873 421592  -24719  351553 45320 
 (7) Greenland_Sea 669899 618664  51235  564865 105035 
 (8) Baffin_Bay_Gulf_of_St._Lawrence 892167 1093916  -201749  1018780 -126614 
 (9) Canadian_Archipelago 852422 838509  13913  830604 21818 
 (10) Hudson_Bay 1160950 1194448  -33497  1167310 -6360 
 (11) Central_Arctic 3242075 3223985  18089  3234305 7769 
 (12) Bering_Sea 271137 293222  -22085  298268 -27130 
 (13) Baltic_Sea 3752 7215 -3463  6368 -2617 
 (14) Sea_of_Okhotsk 220784 188072  32712  164833 55951 

Overall NH extent March 31 was below average by 200k km2,  equivalent to the deficit in Baffin Bay.  Elsewhere smaller deficits were offset with surpluses. The onset of spring melt is as usual in most regions.

April 2021 Resilient Arctic Ice

 

ArcApr2021 107 to 120

Previous posts noted how Arctic ice extents waxed and waned in response to the wavy Polar Vortex this year.  The animation above showed how the ice fluctuated over the last two weeks.  Okhhotsk upper left steadily lost ~225k km2, while Bering Sea lower left lost ~130k km2 in the first week then waffled around the same extent.  Barents at the top lost ~170k km2 early, then in the last 10 days gained back most of it. Greenland Sea middle right waffled down and up with little change up to yesterday.  Baffin Bay lower right produced the largest deficit on the Atlantic side ~180k km2.

The effect on NH total ice extents is presented in the graph below.Arctic2021120The graph above shows ice extent through April comparing 2021 MASIE reports with the 14-year average, other recent years and with SII.  The average April drops about 1.1M km2 of ice extent.  This year MASIE showed two sharp drops and two recoveries, the last one coming close to average day 118.  SII showed a less than average April loss of ~870k km2.  In the end MASIE 2021 matched 2020, and higher then 2007.

The table below shows the distribution of sea ice across the Arctic regions.

Region 2021120 Day 120 Average 2021-Ave. 2007120 2021-2007
 (0) Northern_Hemisphere 13311402 13551290  -239888  13108068 203334 
 (1) Beaufort_Sea 1058557 1068405  -9848  1059189 -632 
 (2) Chukchi_Sea 962680 954463  8217  949246 13434 
 (3) East_Siberian_Sea 1087137 1085503  1635  1080176 6961 
 (4) Laptev_Sea 897827 888936  8891  875661 22166 
 (5) Kara_Sea 915674 911257  4417  864664 51010 
 (6) Barents_Sea 572380 558256  14124  396544 175837 
 (7) Greenland_Sea 605335 649955  -44620  644438 -39103 
 (8) Baffin_Bay_Gulf_of_St._Lawrence 1004774 1231673  -226899  1147115 -142341 
 (9) Canadian_Archipelago 854597 848502  6095  838032 16565 
 (10) Hudson_Bay 1236512 1242200  -5687  1222074 14439 
 (11) Central_Arctic 3239759 3238255  1504  3241034 -1275 
 (12) Bering_Sea 426670 473606  -46936  475489 -48819 
 (13) Baltic_Sea 12293 20617.28786 -8324  14684 -2390 
 (14) Sea_of_Okhotsk 435360 376555  58804  295743 139617 

Overall NH extent March 31 was below average by 240k km2, or 2%.  With Bering deficit offset by Okhotsk surplus, the entire difference from average matches the Baffin Bay deficit. The onset of spring melt is as usual in most regions.

March 2021 Arctic Ice Persists

March Arctic ice 2007 to 2021

Previous posts showed 2021 Arctic Ice fell short of breaking the 15M km2 ceiling mid March due to a February Polar Vortex disruption.  As we shall see below, another smaller PV disruption is now occurring accelerating the normal spring melting season.  The graph above shows that the March monthly average has varied little since 2007, typically around the SII average of 14.7 M km2.  Of course there are regional differences as described later on.

Dr. Judah Cohen at AER provides an image of how this latest PV disruption appears:

gfs_animation_010hpa_20210322_20210407

The High pressure areas were forecast to warm over the Pacific Arctic basins, and extending over to the European side, while the cold Low area is presently extending down into North America, bringing some snow on April 1 in Montreal (no joke).  The effect on Arctic Ice is shown in the animation below:

ArcticMarch2021 080 to 090

Over the last 10 days, Okhotsk upper left lost 180k km2 while Bering lower left lost half that with a slight recovery yesterday.  Barents Sea upper right lost 145k km2 over the same period.  The effect on NH total ice extents is presented in the graph below.

Arctic2021090

The graph above shows ice extent through March comparing 2021 MASIE reports with the 14-year average, other recent years and with SII.  After drawing close to average by day 80, 2021 ice extents dropped sharply and at March end matched both 2020 and 2007.  Despite losses from this PV event, the 2020 March monthly average ended up comparable to other years, as seen in the chart at the top.  In fact, the SII dataset of monthly gains and losses shows March 2021 gained slightly over end of February, compared to a 200k km2 loss for the average March.

 

The table below shows the distribution of sea ice across the Arctic regions.

Region 2021090 Day 090 Average 2021-Ave. 2007090 2021-2007
 (0) Northern_Hemisphere 14266634 14692014  -425380  14222916 43718 
 (1) Beaufort_Sea 1070689 1070177  512  1069711 978 
 (2) Chukchi_Sea 966006 964100  1907  966006
 (3) East_Siberian_Sea 1087137 1086134  1003  1074908 12229 
 (4) Laptev_Sea 897827 896838  989  884340 13487 
 (5) Kara_Sea 935023 916581  18442  892157 42866 
 (6) Barents_Sea 602392 649566  -47174  441970 160422 
 (7) Greenland_Sea 620574 658050  -37476  686312 -65739 
 (8) Baffin_Bay_Gulf_of_St._Lawrence 1243739 1438412  -194673  1217467 26272 
 (9) Canadian_Archipelago 854597 852959  1638  850127 4470 
 (10) Hudson_Bay 1260903 1254727  6176  1229995 30908 
 (11) Central_Arctic 3192844 3234463  -41619  3242237 -49393 
 (12) Bering_Sea 549939 736829  -186890  814788 -264849 
 (13) Baltic_Sea 33543 608741 -27331  45897 -12354 
 (14) Sea_of_Okhotsk 942085 861234  80850  794657 147428 

Overall NH extent March 31 was below average by 425k km2, or 3%.  The bulk of the deficit is seen in Bering and Baffin, along with Barents Sea.  Okhotsk remains above average in spite of recent losses.  The onset of spring melt is as usual in most regions.

March 25 Arctic Melt Season Ensues

As anticipated in a previous post, Arctic ice extent appears to have peaked under the 15M km2 threshold.  An earlier discussion noted that the wavy Polar Vortex that froze Texas with cold Arctic air in February, allowed warmer southern air into Arctic regions, reducing ice extent.  The ice recovered afterward ( see March 1, 2021 Arctic Ice Recovers from PV Hit ), but 2021 was no longer going to reach 15M km2.  As shown by the graph below, ice extents this year did persist and draw close to the 14 year average, before beginning the melt season this week.

Arctic2021083

Starting March MASIE 2021 shows Arctic extents were about 400k km2 below average, but for the first 20 days added 200k while the average lost about 100k, reducing the difference to 85k km2 on day 80.  Now in the last 3 days the melt season has erased the gains in 2021 and restored the deficit to nearly 300k km2, 2% of the 14-year average.  SII reported mostly lower extents than MASIE, but presently the two are similar.  The table shows the distribution of ice over the Arctic regions.

Region 2021083 Day 083 Average 2021-Ave. 2007083 2021-2007
 (0) Northern_Hemisphere 14565743 14844057 -278315 14412819 152924
 (1) Beaufort_Sea 1070689 1070239 450 1069711 978
 (2) Chukchi_Sea 966006 965879 127 966006 0
 (3) East_Siberian_Sea 1087137 1087066 72 1087137 0
 (4) Laptev_Sea 897827 897599 228 897845 -18
 (5) Kara_Sea 935023 918802 16221 904153 30870
 (6) Barents_Sea 689316 649153 40163 472230 217086
 (7) Greenland_Sea 657096 631454 25642 609918 47178
 (8) Baffin_Bay_Gulf_of_St._Lawrence 1284957 1509201 -224244 1323453 -38496
 (9) Canadian_Archipelago 854597 853068 1529 852767 1830
 (10) Hudson_Bay 1260903 1260717 186 1259717 1186
 (11) Central_Arctic 3203492 3230083 -26591 3234061 -30569
 (12) Bering_Sea 592244 746974 -154730 883221 -290977
 (13) Baltic_Sea 46648 70687.87 -24040 70484 -23836
 (14) Sea_of_Okhotsk 1010021 938704 71317 765577 244443

Interestingly, both Okhotsk and Barents Seas peaked well above average, and are still in surplus after starting to retreat.  The main deficits are in Bering and Baffin Bay.  The central Arctic, Siberian and Canadian regions remain solidly frozen.

Background previous post Arctic Ice Moment of Truth 2021

For ice extent in the Arctic, the bar is set at 15M km2. The average peak in the last 14 years occurs on day 62 at 15.04M km2 before descending, though the average can still be above 15M at late as day 73.  Nine of the last 14 years were able to clear 15M, but recently only 2016 and 2020 ice extents cleared the bar at 15M km2; the others came up short. The actual annual peak ice extent day varied between day 59 (2016) to day 82 (2012).

The animation shows in two weeks how this year’s ice extents contracted and then regrew greater than before, coincidental with the wavy Polar Vortex (PV) first admitting warmer southern air and then keeping the cold air in.

As reported previously, most of the action was firstly in the Pacific, especially Sea of Okhotsk upper left, ice shrinking one week by 200k km2 and rapidly growing back 210k km2 ice extent the next.  Okhotsk ice is now 1.1M km2, 96% of 2020 max.  On the Atlantic side, Barents sea upper right lost 100k km2 retreating from Svalbard, then gained 120k km2 back.  Greenland Sea ice middle right lost 100k km2, and then gained 150k km2.  Barents now has 3% more ice than 2020 max, while Greenland sea ice is 85% of last year’s max.

Drift ice in Okhotsk Sea at sunrise.

For more on the Pacific basins see post Meet Bering and Okhotsk Seas

Mid March Arctic Ice Update

As anticipated in the previous post reprinted below, Arctic ice extent appears to have peaked under the 15M km2 threshold.  An earlier discussion at 2020 year end noted that March actually ends up with less ice extent than end of February, so the rest of the month is not likely to add any more ice.  Here is the graph for March including yesterday.

Arctic2021073

The graph shows this year did recover from a 400k km2 deficit to the 14-year average, to about 100k by day 70, and has now fallen back to almost 300k km2 down (2%).  It is also apparent that extent will likely decline in the next two weeks, by about 300k km2 on average, already matched by 2021.  Climatology uses SII March monthly average as the annual maximum, so that will come out lower as well.

Interestingly, both Okhotsk and Barents Seas peaked well above 2020, and are now starting to retreat, along with other marginal basins.  The central Arctic, Siberian and Canadian regions remain solidly frozen.

Background previous post Arctic Ice Moment of Truth 2021

For ice extent in the Arctic, the bar is set at 15M km2. The average peak in the last 14 years occurs on day 62 at 15.04M km2 before descending, though the average can still be above 15M at late as day 73.  Nine of the last 14 years were able to clear 15M, but recently only 2016 and 2020 ice extents cleared the bar at 15M km2; the others came up short. The actual annual peak ice extent day varied between day 59 (2016) to day 82 (2012).

The animation shows in two weeks how this year’s ice extents contracted and then regrew greater than before, coincidental with the wavy Polar Vortex (PV) first admitting warmer southern air and then keeping the cold air in.

As reported previously, most of the action was firstly in the Pacific, especially Sea of Okhotsk upper left, ice shrinking one week by 200k km2 and rapidly growing back 210k km2 ice extent the next.  Okhotsk ice is now 1.1M km2, 96% of 2020 max.  On the Atlantic side, Barents sea upper right lost 100k km2 retreating from Svalbard, then gained 120k km2 back.  Greenland Sea ice middle right lost 100k km2, and then gained 150k km2.  Barents now has 3% more ice than 2020 max, while Greenland sea ice is 85% of last year’s max.

All of this means that 2021 will be hard pressed to pass the 15M km2 threshold.  The graph below shows the situation evolving over the last two weeks anticipating the annual maximum to appear within the fortnight.

Note that Sea Ice Index (SII) went offline day 51 so the MASIE record alone shows the loss of ice extent ending day 56 and climbing up to the present.  The NH ice extent gap is at 244k km2, or 1.6%.  Since the 14 year average has already peaked, further growth will narrow the margin.  (Note that ice extent is affected also by winds piling up drift ice, as well as melting from intrusions of warmer air or water.)

Last year surpassed the average while other recent years were lower.  We shall see what this year does with only 10 days or so to make a difference.

Region 2021063 Day 063 Average 2021-Ave. 2007063 2021-2007
 (0) Northern_Hemisphere 14772617 15016830 -244214 14665491 107126
 (1) Beaufort_Sea 1070689 1070254 435 1069711 978
 (2) Chukchi_Sea 966006 964118 1888 966006 0
 (3) East_Siberian_Sea 1087120 1087134 -14 1087137 -17
 (4) Laptev_Sea 897827 897842 -15 897845 -18
 (5) Kara_Sea 935006 929650 5356 932067 2939
 (6) Barents_Sea 805710 649490 156220 626044 179666
 (7) Greenland_Sea 669651 625085 44566 616841 52809
 (8) Baffin_Bay_Gulf_of_St._Lawrence 1224508 1553901 -329393 1220513 3995
 (9) Canadian_Archipelago 854597 853148 1450 852767 1830
 (10) Hudson_Bay 1260471 1260567 -96 1256718 3753
 (11) Central_Arctic 3197627 3222365 -24738 3229824 -32197
 (12) Bering_Sea 631115 686765 -55650 660726 -29612
 (13) Baltic_Sea 65146 97873 -32727 104884 -39738
 (14) Sea_of_Okhotsk 1090295 1084593 5703 1129107 -38812

The main deficit to average is in Baffin Bay, partly offset by a surplus in Barents.  Smaller pluses and minuses are found in other regions.

Typically, Arctic ice extent loses 67 to 70% of the March maximum by mid September, before recovering the ice in building toward the next March.

What will the ice do this year?  Where will 2020 rank in the annual Arctic Ice High Jump competition?

Drift ice in Okhotsk Sea at sunrise.

For more on the Pacific basins see post Meet Bering and Okhotsk Seas

Arctic Ice Moment of Truth 2021

For ice extent in the Arctic, the bar is set at 15M km2. The average peak in the last 14 years occurs on day 62 at 15.04M km2 before descending, though the average can still be above 15M at late as day 73.  Nine of the last 14 years were able to clear 15M, but recently only 2016 and 2020 ice extents cleared the bar at 15M km2; the others came up short. The actual annual peak ice extent day varied between day 59 (2016) to day 82 (2012).

The animation shows in two weeks how this year’s ice extents contracted and then regrew greater than before, coincidental with the wavy Polar Vortex (PV) first admitting warmer southern air and then keeping the cold air in.

As reported previously, most of the action was firstly in the Pacific, especially Sea of Okhotsk upper left, ice shrinking one week by 200k km2 and rapidly growing back 210k km2 ice extent the next.  Okhotsk ice is now 1.1M km2, 96% of 2020 max.  On the Atlantic side, Barents sea upper right lost 100k km2 retreating from Svalbard, then gained 120k km2 back.  Greenland Sea ice middle right lost 100k km2, and then gained 150k km2.  Barents now has 3% more ice than 2020 max, while Greenland sea ice is 85% of last year’s max.

All of this means that 2021 will be hard pressed to pass the 15M km2 threshold.  The graph below shows the situation evolving over the last two weeks anticipating the annual maximum to appear within the fortnight.

Note that Sea Ice Index (SII) went offline day 51 so the MASIE record alone shows the loss of ice extent ending day 56 and climbing up to the present.  The NH ice extent gap is at 244k km2, or 1.6%.  Since the 14 year average has already peaked, further growth will narrow the margin.  (Note that ice extent is affected also by winds piling up drift ice, as well as melting from intrusions of warmer air or water.)

Last year surpassed the average while other recent years were lower.  We shall see what this year does with only 10 days or so to make a difference.

Region 2021063 Day 063 Average 2021-Ave. 2007063 2021-2007
 (0) Northern_Hemisphere 14772617 15016830 -244214 14665491 107126
 (1) Beaufort_Sea 1070689 1070254 435 1069711 978
 (2) Chukchi_Sea 966006 964118 1888 966006 0
 (3) East_Siberian_Sea 1087120 1087134 -14 1087137 -17
 (4) Laptev_Sea 897827 897842 -15 897845 -18
 (5) Kara_Sea 935006 929650 5356 932067 2939
 (6) Barents_Sea 805710 649490 156220 626044 179666
 (7) Greenland_Sea 669651 625085 44566 616841 52809
 (8) Baffin_Bay_Gulf_of_St._Lawrence 1224508 1553901 -329393 1220513 3995
 (9) Canadian_Archipelago 854597 853148 1450 852767 1830
 (10) Hudson_Bay 1260471 1260567 -96 1256718 3753
 (11) Central_Arctic 3197627 3222365 -24738 3229824 -32197
 (12) Bering_Sea 631115 686765 -55650 660726 -29612
 (13) Baltic_Sea 65146 97873 -32727 104884 -39738
 (14) Sea_of_Okhotsk 1090295 1084593 5703 1129107 -38812

The main deficit to average is in Baffin Bay, partly offset by a surplus in Barents.  Smaller pluses and minuses are found in other regions.

Typically, Arctic ice extent loses 67 to 70% of the March maximum by mid September, before recovering the ice in building toward the next March.

What will the ice do this year?  Where will 2020 rank in the annual Arctic Ice High Jump competition?

Drift ice in Okhotsk Sea at sunrise.

For more on the Pacific basins see post Meet Bering and Okhotsk Seas

March 1, 2021 Arctic Ice Recovers from PV Hit

 

Update March 1, 2021 to previous post

This update is to note a dramatic effect on Okhotsk Sea ice coincidental with the Polar Vortex (PV) event that froze Texas and other midwestern US states mid-February.  When Arctic air extends so far south due to the weak and wavy vortex, warmer air replaces the icy air in Arctic regions.  In this case, the deficits to sea ice extent appeared mostly in the Sea of Okhotsk in the Pacific and Barents Sea in the Atlantic.  After a sharp drop, ice extents are again building toward the Arctic annual maximum, typically mid-March.

The animation above shows the drop and recovery in the last two weeks.  In the Pacific, the PV did little to Bering Sea ice on the lower left, ending the month up about 50k km2.  More dramatic was the PV effect in Okhotsk upper left, where 200k km2 of ice was lost in 5 days, followed by gaining it all back plus some new ice to reach a new high for the year at 95% of 2020 March maximum.  In the Atlantic Barents Sea upper right first retreats from Svalbard, before refreezing.  Middle right Greenland Sea ice is seen receding and then growing, while bottom right Baffin Bay shows a similar pattern. Barents Sea ice was higher than last year,  before losing 175k km2 during the PV, then recovering some back ending the month at 95% of March 2020 maximum.

The graph below shows the February drop and recovery.

Note both MASIE and SII showing a peak of 14.6M km2 nearing the 14-year average on day 46.  Something went wrong with SII, which has not updated its record since day 50.  MASIE has continued, showing losses down to day 56, followed by a sharp rise ending the month at 14.7M km2, a new max for the year.

Some comments from Dr. Judah Cohen Feb. 15 from his AER blog Arctic Oscillation and Polar Vortex Analysis and Forecasts  Excerpts in italics with my bolds.

I have been writing how the stratospheric PV disruption that has been so influential on our weather since mid-January has been unusual and perhaps even unique in the observational record, so I guess then it should be no surprise that it’s ending is also highly unusual. I was admittedly skeptical, but it does seem that the coupling between the stratospheric PV and the tropospheric circulation is about to come to an abrupt end.

The elevated polar cap geopotential height anomalies (PCHs) related to what I like to refer to the third and final PV disruption at the end of January/early February quickly propagates to the surface and even amplifies, peaking this past weekend. And as I have argued, it is during spikes in PCH when severe winter is most likely across the NH mid-latitudes, as demonstrated in Cohen et al. (2018).

But rather than the typical gradual influence from the stratospheric PV disruption over many weeks, maybe akin to the drip, drip, drip of a leaky faucet, the entire signal dropped all at once like an anchor. This also likely contributed to the severity of the current Arctic outbreak in the Central US that is generational and even historical in its severity. But based on the forecast the PV gave all it had all at once, and the entire troposphere-stratosphere-troposphere coupling depicted in Figure ii is about to abruptly end in the next few days.

I am hesitant to bring analogs before 2000 but the extreme cold in Texas did remind me of another winter that brought historic Arctic outbreaks including cold to Texas – January 1977. It does appear that the downward influence from the stratospheric PV to the surface came to an abrupt end at the end of January 1977 . . . Relative to normal, January 1977 was the coldest month for both Eurasia and the US when stratosphere-troposphere coupling was active. But the relative cold did persist in both the Eastern US and northern Eurasia in February post the stratosphere-troposphere coupling. By March the cold weather in the Eastern US was over but persisted for northern Eurasia.

See also No, CO2 Doesn’t Drive the Polar Vortex

Background from Previous Post

In January, most of the Arctic ocean basins are frozen over, and so the growth of ice extent slows down.  According to SII (Sea Ice Index) January on average adds 1.3M km2, and this month it was 1.4M.  (background is at Arctic Ice Year-End 2020).  The few basins that can grow ice this time of year tend to fluctuate and alternate waxing and waning, which appears as a see saw pattern in these images.

Two weeks into February Arctic ice extents are growing faster than the 14-year average, such that they are approaching the mean.  The graph below shows the ice recovery since mid-January for 2021, the 14-year average and several recent years.

The graph shows mid January a small deficit to average, then slow 2021 growth for some days before picking up the pace in the latter weeks.  Presently extents are slightly (1%) below average, close to 2019 and 2020 and higher than 2018.

February Ice Growth Despite See Saws in Atlantic and Pacific

As noted above, this time of year the Arctic adds ice on the fringes since the central basins are already frozen over.  The animation above shows Barents Sea on the right (Atlantic side) grew in the last two weeks by 175k km2 and is now 9% greater than the maximum last March.  Meanwhile on the left (Pacific side)  Bering below and Okhotsk above wax and wane over this period. Okhotsk is seen growing 210k km2 the first week, and giving half of it back the second week.  Bering waffles up and down ending sightly higher in the end.

The table below presents ice extents in the Arctic regions for day 44 (Feb. 13) compared to the 14 year average and 2018.

Region 2021044 Day 044 Average 2021-Ave. 2018044 2021-2018
 (0) Northern_Hemisphere 14546503 14678564 -132061 14140166 406337
 (1) Beaufort_Sea 1070689 1070254 435 1070445 244
 (2) Chukchi_Sea 966006 965691 315 965971 35
 (3) East_Siberian_Sea 1087120 1087134 -14 1087120 0
 (4) Laptev_Sea 897827 897842 -15 897845 -18
 (5) Kara_Sea 934988 906346 28642 874714 60274
 (6) Barents_Sea 837458 563224 274235 465024 372434
 (7) Greenland_Sea 645918 610436 35482 529094 116824
 (8) Baffin_Bay_Gulf_of_St._Lawrence 1057623 1487547 -429924 1655681 -598058
 (9) Canadian_Archipelago 854597 853146 1451 853109 1489
 (10) Hudson_Bay 1260471 1260741 -270 1260838 -367
 (11) Central_Arctic 3206263 3211892 -5630 3117143 89120
 (12) Bering_Sea 559961 674196 -114235 319927 240034
 (13) Baltic_Sea 116090 94341 21749 76404 39686
 (14) Sea_of_Okhotsk 1027249 930357 96892 911105 116144
 (15) Yellow_Sea 9235 28237 -19002 33313 -24078
 (16) Cook_Inlet 223 11137 -10914 11029 -10806

The table shows that Bering defict to average is offset by surplus in Okhotsk.  Baffin Bay show the largest deficit, mostly offset by surpluses in Barents, Kara and Greenland Sea.

The polar bears have a Valentine Day’s wish for Arctic Ice.

welovearcticicefinal

And Arctic Ice loves them back, returning every year so the bears can roam and hunt for seals.

Footnote:

Seesaw accurately describes Arctic ice in another sense:  The ice we see now is not the same ice we saw previously.  It is better to think of the Arctic as an ice blender than as an ice cap, explained in the post The Great Arctic Ice Exchange.