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Author Topic: 2017 sea ice area and extent data  (Read 80507 times)

Tor Bejnar

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Re: 2017 sea ice area and extent data
« Reply #350 on: July 23, 2017, 06:19:23 PM »
Upticks both in extent and area. ...
Without actually going back to document my sense, I believe several folks (I was mum on the issue, having somewhat learned the lessen Jim & Terry named) predicted a melting lull that seems to have occurred a little later than expected, but here, none-the-less.  (And congratulations to you unnamed individuals!)
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BornFromTheVoid

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Re: 2017 sea ice area and extent data
« Reply #351 on: July 23, 2017, 06:41:26 PM »
A double update today, to make up for missing out last weekend.

Update for the week to July 15th

The current 5 day trailing average is on 8,114,000km2 while the 1 day extent is at 7,857,000km2.

(All the following data is based on a trailing 5 day average)
The daily anomaly (compared to 81-10) is at -1,638,000km2, an increase from -1,498,000km2 last week. The anomaly compared to the 07, 11 and 12 average is at +134,000km2, an increase from +63,000km2 last week. We're currently 4th lowest on record, up from 5th lowest last week.



The average daily change over the last 7 days was -101.5k/day, compared to the long term average of -81.5k/day, and the 07, 11 and 12 average of -111.6k/day.
The average long term change over the next week is -89.3k/day, with the 07, 11, and 12 average being -90.9k/day.



The extent loss so far this July is the 10th largest on record. To achieve the largest loss, a drop of at least 125.0k/day is required (more than -124.4k/day with single day values), while the smallest loss requires a drop of less than 30.8k/day (less than 16.8k/day with single day values) and an average loss requires a drop of 71.8k/day (63.7k/day with single day values).


BornFromTheVoid

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Re: 2017 sea ice area and extent data
« Reply #352 on: July 23, 2017, 06:44:36 PM »
Update for the week to July 22nd

The current 5 day trailing average is on 7,417,000km2 while the 1 day extent is at 7,289,000km2.

(All the following data is based on a trailing 5 day average)
The daily anomaly (compared to 81-10) is at -1,710,000km2, an increase from -1,638,000km2 last week. The anomaly compared to the 07, 11 and 12 average is at +74,000km2, a decrease from +134,000km2 last week. We're currently 3rd lowest on record, up from 4th lowest last week.



The average daily change over the last 7 days was -99.6k/day, compared to the long term average of -89.3k/day, and the 07, 11 and 12 average of -90.9k/day.
The average long term change over the next week is -87.1k/day, with the 07, 11, and 12 average being -81.6k/day.



The extent loss so far this July is the 7th largest on record. To achieve the largest loss, a drop of at least 144.7k/day is required (more than -167.6k/day with single day values), while the smallest loss requires an increase of over 22.7k/day (over 47.5k/day with single day values) and an average loss requires a drop of 50.1k/day (46.2k/day with single day values).


Jim Hunt

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Re: 2017 sea ice area and extent data
« Reply #353 on: July 23, 2017, 06:46:08 PM »
I believe several folks (I was mum on the issue, having somewhat learned the lessen Jim & Terry named) predicted a melting lull that seems to have occurred a little later than expected.

Bear in mind that the "melting lull" might merely be an artifact of the way NSIDC do their sums (math as they call it in the good ol' U S of A). The JAXA and "homebrew" AMSR2 numbers are still declining, and as Wipneus put it:

The 15% cutoff may play a role here
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Neven

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Re: 2017 sea ice area and extent data
« Reply #354 on: July 23, 2017, 11:55:28 PM »
One final off-topic post (as it happened in this thread): I've been having some PM conversations with some of the folks involved, and have stressed again that it isn't the 'going out on a limb' that is the problem per se, but the reaction to the push-back that inevitably follows. I've asked again to refrain from sarcasm and Galileo-arguments. At the same time I want to ask those who are annoyed by it (including myself) to try and be less annoyed by it.

Given the seriousness of Arctic sea ice loss and AGW, I'm afraid this dynamic will remain part of the ASIF for a while to come. I will try and keep a balance as best as I can. I've always stressed that to me the over-all atmosphere on the Forum is most important, while allowing room for heated debates, frustrations and the occasional insults, of course. It's not a hospital.

Anyone wanting to discuss more, might do so on the 'climate porn vs not alarmed enough' thread. Unfortunately I haven't had the time to follow or participate in that discussion.

Okay, back on-topic now. I think we'll know more in one-two weeks from now, as more data comes in during this period where a persistent cyclone should cause something of a stall.  Let's watch together and analyze as it happens.
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Tigertown

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Re: 2017 sea ice area and extent data
« Reply #355 on: July 24, 2017, 01:15:25 AM »
I believe several folks (I was mum on the issue, having somewhat learned the lessen Jim & Terry named) predicted a melting lull that seems to have occurred a little later than expected.

Bear in mind that the "melting lull" might merely be an artifact of the way NSIDC do their sums (math as they call it in the good ol' U S of A). The JAXA and "homebrew" AMSR2 numbers are still declining, and as Wipneus put it:

The 15% cutoff may play a role here
.
I figured it to be a little bit of 'spersion.

Jim Pettit

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Re: 2017 sea ice area and extent data
« Reply #356 on: July 24, 2017, 01:46:38 PM »
Interesting factoid: between 2000 and this year, NSIDC has only seen three July days on which extent has increased by more than 30k. One was in 2010; the other two were the two just passed. Or to look at it another way: the average two-day SIE change at this time of year from 2000 through 2016 was -176k; this year has seen +84k. (It's also the largest two-day increase in NSIDC extent since the first week of April.)

NSIDC extent has fallen the past two days from 2nd place to 5th.

Wipneus

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Re: 2017 sea ice area and extent data
« Reply #357 on: July 24, 2017, 02:38:38 PM »
Indeed another uptick in extent, +37k7. Area managed to drop a similar amount, mostly CAB.

Regional Arctic Sea Ice Extent and Area calculated from NSIDC NASA Team concentration data
Date: 2017-07-23 12:00  Values in 1000 km^2

Extent (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  4426.5   +9.2    -0.3    436.8  -12.7  -368.5    486.3  +19.3   -65.2
               Kara Sea             Barents Sea           Greenland Sea
   214.2   +5.8  -325.7     56.4   +1.8  -101.0    252.0  -12.7  -144.8
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
   308.9  +10.5   -12.0      9.9   +3.2    +9.9    153.3   +7.3  -127.5
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   554.1   -0.8  -102.2    265.3   -0.1  -119.6    121.6   -1.1  -197.9
             Bering Sea          Sea of Okhotsk                   Lakes
    16.2   +5.4   +10.7     22.9   +2.7   +22.9    151.0  +29.3   +24.4
          Other regions       Total (ex. lakes)
     2.9   +0.0    +2.9   7327.2  +37.7 -1518.1

Area (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  3494.1  -40.5  -204.8    210.5   -6.7  -305.3    262.4  +16.0   -79.7
               Kara Sea             Barents Sea           Greenland Sea
    95.0   +5.3  -228.9     15.1   -2.3   -51.9    103.9  -11.1   -86.2
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
   131.3   +3.8    -9.0      2.3   +0.9    +2.3     55.7   -1.0   -66.4
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   364.8   +6.0   -67.5    144.4  -11.8  -100.0     45.9   +0.3  -141.1
             Bering Sea          Sea of Okhotsk                   Lakes
     3.2   +1.0    +1.9      6.0   +1.3    +6.0     90.8  +16.2   +35.4
          Other regions       Total (ex. lakes)
     2.2   -0.0    +2.2   4936.9  -38.7 -1328.6


Delta map attached: red/blue means the concentration went below/over the 15% cut-off. Reddish/bluish means the concentration decreased/increased by more than 7%.

greatdying2

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Re: 2017 sea ice area and extent data
« Reply #358 on: July 24, 2017, 11:22:49 PM »
I've asked again to refrain from sarcasm and Galileo-arguments. At the same time I want to ask those who are annoyed by it (including myself) to try and be less annoyed by it.
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Wipneus

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Re: 2017 sea ice area and extent data
« Reply #359 on: July 25, 2017, 06:11:09 PM »
Also extent and area from  NSIDC sea ice concentration declines are back to usual rates.

Regional Arctic Sea Ice Extent and Area calculated from NSIDC NASA Team concentration data
Date: 2017-07-24 12:00  Values in 1000 km^2

Extent (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  4422.5   -3.9    -2.5    450.2  +13.3  -347.7    476.1  -10.2   -64.4
               Kara Sea             Barents Sea           Greenland Sea
   213.0   -1.1  -312.9     52.0   -4.4  -103.7    249.7   -2.3  -138.3
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
   293.8  -15.2   -13.7      4.1   -5.8    +4.1    149.4   -3.8  -119.3
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   547.3   -6.7   -98.9    237.3  -27.9  -144.9     99.5  -22.1  -218.6
             Bering Sea          Sea of Okhotsk                   Lakes
    11.4   -4.8    +5.8     33.0  +10.1   +33.0    185.8  +34.3   +63.9
          Other regions       Total (ex. lakes)
     2.9   +0.0    +2.9   7242.2  -85.0 -1519.1

Area (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  3484.5   -9.6  -203.3    212.4   +1.9  -295.3    247.3  -15.1   -87.7
               Kara Sea             Barents Sea           Greenland Sea
    92.1   -2.9  -222.4     15.0   -0.1   -51.0    100.4   -3.5   -84.9
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
   122.1   -9.3   -12.0      1.1   -1.2    +1.1     54.3   -1.4   -61.0
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   348.9  -15.9   -73.9    142.7   -1.7   -95.6     36.8   -9.1  -144.3
             Bering Sea          Sea of Okhotsk                   Lakes
     2.4   -0.8    +1.1     10.9   +5.0   +10.9    100.0   +9.2   +45.8
          Other regions       Total (ex. lakes)
     2.3   +0.1    +2.3   4873.4  -63.5 -1316.0


Delta map attached: red/blue means the concentration went below/over the 15% cut-off. Reddish/bluish means the concentration decreased/increased by more than 7%.

Wipneus

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Re: 2017 sea ice area and extent data
« Reply #360 on: July 26, 2017, 06:58:17 PM »
Laptev and ESS contribute most. Ice in the north of the Hudson region (Foxe Basin) is being cleared as well.

Regional Arctic Sea Ice Extent and Area calculated from NSIDC NASA Team concentration data
Date: 2017-07-25 12:00  Values in 1000 km^2

Extent (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  4426.5   +3.9    +5.2    424.0  -26.2  -368.4    448.6  -27.5   -79.9
               Kara Sea             Barents Sea           Greenland Sea
   209.1   -3.9  -304.3     52.7   +0.8   -94.7    230.2  -19.5  -148.5
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
   281.8  -12.0   -12.8      6.7   +2.6    +6.7    130.6  -18.9  -128.3
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   557.4  +10.1   -83.4    248.1  +10.8  -134.0    104.7   +5.2  -209.2
             Bering Sea          Sea of Okhotsk                   Lakes
     5.4   -6.0    +0.1     20.9  -12.1   +20.9    176.1  -10.1   +54.6
          Other regions       Total (ex. lakes)
     2.9   +0.0    +2.9   7149.6  -92.6 -1527.7

Area (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  3499.0  +14.5  -179.0    196.3  -16.1  -306.9    234.1  -13.2   -87.5
               Kara Sea             Barents Sea           Greenland Sea
    94.8   +2.7  -208.4     16.3   +1.3   -47.3     99.2   -1.2   -80.7
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
   113.6   -8.5   -12.0      1.4   +0.3    +1.4     45.5   -8.8   -63.9
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   345.1   -3.8   -68.6    130.3  -12.4  -104.2     36.7   -0.1  -139.4
             Bering Sea          Sea of Okhotsk                   Lakes
     2.4   -0.0    +1.0      4.8   -6.1    +4.8     95.3   -4.9   +40.3
          Other regions       Total (ex. lakes)
     2.2   -0.0    +2.2   4821.8  -51.6 -1288.6


Delta map attached: red/blue means the concentration went below/over the 15% cut-off. Reddish/bluish means the concentration decreased/increased by more than 7%.

Wipneus

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Re: 2017 sea ice area and extent data
« Reply #361 on: July 27, 2017, 06:07:58 PM »
Extent increases in the north of the Hudson region offsets extent drops in ESS and Laptev. Area in those regions does changes less, so my impression is that there is little actual melting.

Regional Arctic Sea Ice Extent and Area calculated from NSIDC NASA Team concentration data
Date: 2017-07-26 12:00  Values in 1000 km^2

Extent (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  4421.9   -4.6    +4.0    386.3  -37.6  -393.2    433.3  -15.3   -85.0
               Kara Sea             Barents Sea           Greenland Sea
   213.0   +3.9  -289.2     41.1  -11.6  -105.0    225.8   -4.4  -145.7
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
   283.6   +1.8    -0.4      8.3   +1.6    +8.3    162.7  +32.2   -89.9
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   567.7  +10.3   -71.5    252.6   +4.4  -127.1     97.1   -7.6  -210.6
             Bering Sea          Sea of Okhotsk                   Lakes
    13.8   +8.4    +8.7     18.2   -2.7   +18.2    129.7  -46.4    +5.4
          Other regions       Total (ex. lakes)
     2.9   +0.0    +2.9   7128.4  -21.3 -1475.4

Area (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  3514.6  +15.7  -168.6    182.4  -13.9  -313.2    229.0   -5.1   -80.7
               Kara Sea             Barents Sea           Greenland Sea
    91.5   -3.3  -203.9     13.7   -2.6   -48.1     95.4   -3.8   -80.4
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
   109.6   -4.0   -11.2      2.2   +0.8    +2.2     53.3   +7.8   -53.7
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   345.4   +0.3   -61.9    133.1   +2.8   -96.3     33.3   -3.4  -137.4
             Bering Sea          Sea of Okhotsk                   Lakes
     3.8   +1.4    +2.4      4.2   -0.7    +4.2     80.8  -14.4   +25.2
          Other regions       Total (ex. lakes)
     2.1   -0.1    +2.1   4813.6   -8.3 -1244.5


Delta map attached: red/blue means the concentration went below/over the 15% cut-off. Reddish/bluish means the concentration decreased/increased by more than 7%.

Steven

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Re: 2017 sea ice area and extent data
« Reply #362 on: July 28, 2017, 02:22:57 PM »
NSIDC Arctic sea ice area anomaly is now -1.19 million km2, which is 7th lowest for the date:



Compactness:


Wipneus

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Re: 2017 sea ice area and extent data
« Reply #363 on: July 28, 2017, 06:48:29 PM »
Also the NSIDC sea ice concentration drops most in ESS.

Regional Arctic Sea Ice Extent and Area calculated from NSIDC NASA Team concentration data
Date: 2017-07-27 12:00  Values in 1000 km^2

Extent (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  4421.9   +0.0    +5.8    341.2  -45.1  -421.9    437.8   +4.6   -65.1
               Kara Sea             Barents Sea           Greenland Sea
   198.9  -14.1  -293.4     33.2   -7.9  -107.5    216.5   -9.3  -149.7
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
   263.9  -16.7    -9.4      7.8   +0.0    +7.8    138.2  -24.6  -105.6
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   570.1   +2.4   -63.5    251.9   -0.7  -123.6     89.8   -7.3  -210.1
             Bering Sea          Sea of Okhotsk                   Lakes
    14.5   +0.7    +9.4     17.5   -0.7   +17.5    142.0  +12.8   +17.4
          Other regions       Total (ex. lakes)
     2.9   +0.0    +2.9   7006.2 -118.7 -1506.4

Area (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  3552.5  +37.8  -125.6    170.1  -12.4  -314.3    229.3   +0.4   -71.3
               Kara Sea             Barents Sea           Greenland Sea
    84.8   -6.7  -202.9      9.5   -4.1   -49.1     89.5   -5.9   -82.8
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
    96.3  -12.8   -19.3      2.2   +0.1    +2.2     42.5  -10.9   -60.4
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   346.4   +1.1   -54.2    141.2   +8.1   -86.5     28.0   -5.4  -136.9
             Bering Sea          Sea of Okhotsk                   Lakes
     3.0   -0.8    +1.7      4.3   +0.2    +4.3     82.5   +1.8   +27.3
          Other regions       Total (ex. lakes)
     2.1   -0.0    +2.1   4801.7  -11.3 -1192.9


Delta map attached: red/blue means the concentration went below/over the 15% cut-off. Reddish/bluish means the concentration decreased/increased by more than 7%.

Jim Pettit

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Re: 2017 sea ice area and extent data
« Reply #364 on: July 29, 2017, 01:57:38 PM »
NSIDC SIE dropped 196k, just shy of a double century, and the second largest drop this year that didn't occur on the first day of the month. 2017 Extent is already below the minimums measured in 11 earlier seasons (1980-83, 1986-1989, 1992, 1994, and 1996).

Wipneus

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Re: 2017 sea ice area and extent data
« Reply #365 on: July 29, 2017, 03:39:17 PM »
Indeed Jim, and nearly four times as large as the drop in area. The most impressive drop was in the Baffin region, but Laptev, Kara and Chukchi combined was even bigger.

Regional Arctic Sea Ice Extent and Area calculated from NSIDC NASA Team concentration data
Date: 2017-07-28 12:00  Values in 1000 km^2

Extent (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  4415.5   -6.4    +1.6    310.4  -30.8  -436.7    415.5  -22.4   -76.6
               Kara Sea             Barents Sea           Greenland Sea
   180.0  -18.9  -306.5     35.6   +2.4   -97.6    218.5   +2.0  -142.5
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
   209.3  -53.6   -53.3      6.2   -1.6    +6.2    124.9  -13.3  -108.4
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   566.3   -3.8   -63.0    242.4   -9.5  -129.3     58.6  -31.1  -233.7
             Bering Sea          Sea of Okhotsk                   Lakes
     7.8   -6.6    +2.8     16.0   -1.5   +16.0    178.0  +24.7   +54.9
          Other regions       Total (ex. lakes)
     2.9   +0.0    +2.9   6809.9 -195.1 -1618.2

Area (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  3548.0   -4.4  -121.3    155.9  -14.2  -315.6    228.1   -1.2   -65.2
               Kara Sea             Barents Sea           Greenland Sea
    78.4   -6.4  -203.1     10.0   +0.4   -45.6     93.0   +3.5   -76.5
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
    80.0  -16.1   -30.8      1.8   -0.5    +1.8     39.8   -2.6   -58.4
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   346.8   +0.4   -46.9    141.2   +0.0   -87.8     19.1   -8.9  -142.0
             Bering Sea          Sea of Okhotsk                   Lakes
     1.4   -1.6    +0.0      4.0   -0.4    +4.0     93.9   +8.5   +38.9
          Other regions       Total (ex. lakes)
     2.2   +0.1    +2.2   4749.7  -51.9 -1185.3


Delta map attached: red/blue means the concentration went below/over the 15% cut-off. Reddish/bluish means the concentration decreased/increased by more than 7%.

Wipneus

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Re: 2017 sea ice area and extent data
« Reply #366 on: July 30, 2017, 06:22:35 PM »
NSIDC sea ice concentration shows a similar extent drop as UH AMSR2 in the area where Beaufort, Chukchi and CAB border. The drop is "spoiled" by extent rebounds in some regions, Hudson, ESS and Baffin to name a few.

Regional Arctic Sea Ice Extent and Area calculated from NSIDC NASA Team concentration data
Date: 2017-07-29 12:00  Values in 1000 km^2

Extent (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  4395.6  -19.9   -15.2    337.7  +27.3  -396.4    391.1  -24.4   -95.1
               Kara Sea             Barents Sea           Greenland Sea
   170.3   -9.7  -312.7     37.2   +1.6   -85.8    215.4   -3.1  -137.9
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
   221.0  +12.2   -31.9      6.7   +0.5    +6.7    162.4  +37.5   -56.6
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   578.0  +11.7   -43.0    223.3  -19.1  -144.2     37.6  -21.0  -247.6
             Bering Sea          Sea of Okhotsk                   Lakes
     6.0   -1.8    +1.2     12.0   -4.0   +12.0    201.5  +22.5   +77.8
          Other regions       Total (ex. lakes)
     2.9   +0.0    +2.9   6797.2  -12.2 -1543.5

Area (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  3556.4   +8.4  -110.4    168.6  +12.7  -293.1    222.9   -5.2   -65.9
               Kara Sea             Barents Sea           Greenland Sea
    73.1   -5.3  -204.3     11.3   +1.4   -39.2     91.5   -1.5   -73.9
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
    76.9   -3.0   -28.5      1.8   +0.0    +1.8     53.1  +13.3   -37.0
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   335.6  -11.3   -53.1    133.8   -7.4   -90.7     13.6   -5.4  -143.0
             Bering Sea          Sea of Okhotsk                   Lakes
     1.4   +0.1    +0.2      2.7   -1.3    +2.7    100.8   +6.8   +46.4
          Other regions       Total (ex. lakes)
     2.1   -0.1    +2.1   4745.0   -4.7 -1132.3


Delta map attached: red/blue means the concentration went below/over the 15% cut-off. Reddish/bluish means the concentration decreased/increased by more than 7%.

BornFromTheVoid

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Re: 2017 sea ice area and extent data
« Reply #367 on: July 30, 2017, 08:30:45 PM »
Update for the week to July 29th

The current 5 day trailing average is on 7,417,000km2 while the 1 day extent is at 7,289,000km2.

(All the following data is based on a trailing 5 day average)
The daily anomaly (compared to 81-10) is at -1,540,000km2, a decrease from -1,710,000km2 last week. The anomaly compared to the 07, 11 and 12 average is at +205,000km2, an increase from +134,000km2 last week. We're currently 4th lowest on record, down from 3rd lowest last week.



The average daily change over the last 7 days was -62.8k/day, compared to the long term average of -87.1k/day, and the 07, 11 and 12 average of -81.6k/day.
The average long term change over the next week is -81.5k/day, with the 07, 11, and 12 average being -73.0k/day.



The extent loss so far this July is the 15th largest on record. To achieve the largest loss, a drop of at least 431.0k/day is required (more than -1,209.5k/day with single day values), while the smallest loss requires an increase of over 322.0k/day (over 1,303.3k/day with single day values) and an average loss requires a drop of 5.7k/day (an increase of 208.0k/day with single day values).


Wipneus

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Re: 2017 sea ice area and extent data
« Reply #368 on: August 01, 2017, 09:28:19 AM »
Late report of 2017-7-30. The numbers seem skewed by big extent drops in Baffin and Hudson that combined are larger than the total change in extent.

Regional Arctic Sea Ice Extent and Area calculated from NSIDC NASA Team concentration data
Date: 2017-07-30 12:00  Values in 1000 km^2

Extent (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  4408.5  +12.9    -0.5    332.0   -5.6  -388.6    380.3  -10.8   -97.1
               Kara Sea             Barents Sea           Greenland Sea
   169.6   -0.7  -305.8     46.0   +8.8   -70.9    203.6  -11.8  -147.6
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
   185.0  -35.9   -54.5      5.2   -1.6    +5.2    120.7  -41.7   -91.7
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   581.8   +3.8   -32.9    213.2  -10.1  -149.4     55.6  +18.0  -225.1
             Bering Sea          Sea of Okhotsk                   Lakes
    12.7   +6.7    +8.5     18.7   +6.6   +18.7    151.6  -49.8   +26.9
          Other regions       Total (ex. lakes)
     2.9   +0.0    +2.9   6735.7  -61.5 -1528.8

Area (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  3539.5  -16.9  -121.4    152.9  -15.7  -299.5    215.4   -7.5   -65.8
               Kara Sea             Barents Sea           Greenland Sea
    75.5   +2.5  -194.7     13.3   +1.9   -34.5     84.4   -7.1   -79.3
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
    70.6   -6.3   -28.5      1.4   -0.4    +1.4     37.5  -15.6   -48.2
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   347.8  +12.3   -35.3    120.8  -13.1   -98.0     15.1   +1.5  -137.6
             Bering Sea          Sea of Okhotsk                   Lakes
     3.9   +2.5    +2.8      4.8   +2.1    +4.8     85.9  -14.7   +29.7
          Other regions       Total (ex. lakes)
     2.2   +0.1    +2.2   4685.2  -59.8 -1131.6


Delta map attached: red/blue means the concentration went below/over the 15% cut-off. Reddish/bluish means the concentration decreased/increased by more than 7%.

Wipneus

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Re: 2017 sea ice area and extent data
« Reply #369 on: August 01, 2017, 05:18:13 PM »
Big drop in the central basin causes a century area drop in the CAB. ESS has biggest extent drop, but the extent increase in Kara more than compensates that.

Regional Arctic Sea Ice Extent and Area calculated from NSIDC NASA Team concentration data
Date: 2017-07-31 12:00  Values in 1000 km^2

Extent (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  4397.0  -11.5    -9.6    301.4  -30.6  -398.5    372.6   -7.6   -94.9
               Kara Sea             Barents Sea           Greenland Sea
   213.9  +44.4  -253.0     53.7   +7.7   -55.3    196.5   -7.1  -147.6
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
   162.7  -22.4   -65.3      4.1   -1.0    +4.1    113.7   -7.0   -88.6
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   549.0  -32.7   -61.2    203.5   -9.7  -154.6     57.8   +2.2  -206.0
             Bering Sea          Sea of Okhotsk                   Lakes
    14.4   +1.7   +12.3     16.8   -1.8   +16.8    135.9  -15.7   +16.5
          Other regions       Total (ex. lakes)
     2.9   +0.0    +2.9   6660.2  -75.5 -1498.6

Area (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  3411.0 -128.6  -252.1    138.4  -14.4  -299.2    213.7   -1.7   -61.0
               Kara Sea             Barents Sea           Greenland Sea
    84.2   +8.7  -180.7     14.4   +1.1   -31.1     79.7   -4.7   -80.8
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
    58.8  -11.8   -32.8      1.0   -0.4    +1.0     34.8   -2.7   -46.6
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   342.5   -5.4   -34.5    116.9   -3.9  -102.7     14.4   -0.7  -131.4
             Bering Sea          Sea of Okhotsk                   Lakes
     2.9   -1.0    +2.5      3.6   -1.2    +3.6     82.6   -3.3   +30.7
          Other regions       Total (ex. lakes)
     2.2   +0.0    +2.2   4518.4 -166.8 -1243.5


Delta map attached: red/blue means the concentration went below/over the 15% cut-off. Reddish/bluish means the concentration decreased/increased by more than 7%.

Shared Humanity

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Re: 2017 sea ice area and extent data
« Reply #370 on: August 01, 2017, 05:39:57 PM »
Wow! Can Kara possibly be correct? Looking at the image, it seems wrong.

Wipneus

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Re: 2017 sea ice area and extent data
« Reply #371 on: August 01, 2017, 05:45:26 PM »
Update of NSIDC based extent and area graphs for the Basin regions only.
 

Wipneus

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Re: 2017 sea ice area and extent data
« Reply #372 on: August 01, 2017, 05:53:10 PM »
Wow! Can Kara possibly be correct? Looking at the image, it seems wrong.


In case of Kara, there was a polar low just over it. Waves are probably the explanation.


epiphyte

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Re: 2017 sea ice area and extent data
« Reply #373 on: August 01, 2017, 06:49:28 PM »
There's coastal ice "appearing" all over the place today. Did a mask change, or something?

Wipneus

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Re: 2017 sea ice area and extent data
« Reply #374 on: August 01, 2017, 07:01:04 PM »
There's coastal ice "appearing" all over the place today. Did a mask change, or something?

Tomorrow will have a new monthly mask applied, so expect a first-of-the-month drop.

I think the (false) coastal ice in the Bering, Okhotsk and Baltic regions is to disappear, as well as a few minor shavings. Altogether the FOTM drop will be perhaps about 35k extent.

Dharma Rupa

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Re: 2017 sea ice area and extent data
« Reply #375 on: August 01, 2017, 11:22:57 PM »
There's coastal ice "appearing" all over the place today. Did a mask change, or something?

Tomorrow will have a new monthly mask applied, so expect a first-of-the-month drop.

I think the (false) coastal ice in the Bering, Okhotsk and Baltic regions is to disappear, as well as a few minor shavings. Altogether the FOTM drop will be perhaps about 35k extent.

Um...I've been watching you long enough that I want a translation.

I kinda get how you know the satellite's failings, but I just see the woof and wain without enough understanding of what is real and what is a ghost.

Rob Dekker

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Re: 2017 sea ice area and extent data
« Reply #376 on: August 02, 2017, 07:53:17 AM »
Um...I've been watching you long enough that I want a translation.

I kinda get how you know the satellite's failings, but I just see the woof and wain without enough understanding of what is real and what is a ghost.

As Wipneus explained a couple of times :
These masks, created by NSIDC, remove any ice from places where we know no ice does exist. As ice in winter can be found much further south than in summer, a different mask has been created for each month.

NSIDC has a good explanation here :
https://nsidc.org/data/pm/ocean-masks

Jim Pettit

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Re: 2017 sea ice area and extent data
« Reply #377 on: August 02, 2017, 01:37:41 PM »
Exactly a 200k (double-century) drop in NSIDC SIE, plunging 2017 into second place (though just barely) for only the second time since April. Much of that is, of course, from the typical application of NSIDC's first-of-the-month mask. But still: that's a big one, the third largest of the year, and the fifth biggest August drop since 2000 (2003 and 2008 each saw one, and the 2012 GAC induced two).
« Last Edit: August 02, 2017, 01:52:01 PM by Jim Pettit »

Wipneus

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Re: 2017 sea ice area and extent data
« Reply #378 on: August 02, 2017, 02:29:43 PM »
Well Jim, looking at the numbers for Bering , Okhotsk and St.Lawrence the first of the month step was not so big after all 12k or so. So the extent drop is big and is mainly within the Basin. Ice in the Beaufort, Chukchi, CAB border region is getting a beating from a storm, some of the ice apparently lost may pop back in a few days after that is settled. Further ice in the ESS and Laptev looses plenty of extent.

Regional Arctic Sea Ice Extent and Area calculated from NSIDC NASA Team concentration data
Date: 2017-08-01 12:00  Values in 1000 km^2

Extent (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  4357.1  -39.9   -46.5    273.3  -28.1  -427.5    343.2  -29.4  -115.0
               Kara Sea             Barents Sea           Greenland Sea
   224.3  +10.3  -229.2     43.1  -10.6   -62.4    186.2  -10.3  -151.7
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
   156.5   -6.1   -55.6      0.0   -4.1    +0.0    112.8   -0.9   -84.7
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   534.0  -15.0   -68.3    152.0  -51.5  -202.5     41.6  -16.3  -216.9
             Bering Sea          Sea of Okhotsk                   Lakes
     4.2  -10.2    +4.1     20.2   +3.4   +20.2    147.1  +11.1   +24.2
          Other regions       Total (ex. lakes)
    11.8   +8.9   +11.8   6460.5 -199.7 -1624.0

Area (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  3305.0 -106.0  -352.7    139.3   +0.8  -294.0    213.2   -0.5   -56.2
               Kara Sea             Barents Sea           Greenland Sea
    87.3   +3.1  -170.2     11.9   -2.5   -31.2     72.1   -7.5   -85.5
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
    56.4   -2.4   -28.6      0.0   -1.0    +0.0     33.4   -1.5   -43.8
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   327.6  -14.9   -44.7     95.8  -21.1  -119.9     10.7   -3.6  -128.9
             Bering Sea          Sea of Okhotsk                   Lakes
     0.8   -2.1    +0.7      6.2   +2.6    +6.2     87.3   +4.8   +33.2
          Other regions       Total (ex. lakes)
     8.2   +6.0    +8.2   4367.9 -150.5 -1340.5


Delta map attached: red/blue means the concentration went below/over the 15% cut-off. Reddish/bluish means the concentration decreased/increased by more than 7%.

Rob Dekker

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Re: 2017 sea ice area and extent data
« Reply #379 on: August 03, 2017, 08:50:50 AM »
A few days ago, on the "melting" thread I suggested that since ice concentration was running very high (2013/2014 levels), and I suggested that 'extent' was about to 'stall' since typically 'area' is a better indicator of actual ice melt, and 'area' has been running quite high for some time.

Only to get slapped around the ears with two century breaks in 'area' and a double century break in 'extent', while the only thing of significance that could have caused that is a mild storm on the Pacific side. One that 'normally' should actually cool down things, and cause some dispersion.

The only reasonable explanation for these century breaks seems to be that (as many of us have pointed out before) that the ice in 2017 is simply thinner and thus more sensitive than in prior years, just like PIOMAS told us all along. It's just that the effect of that thinner ice is really starting to show up now at the end of the melting season.

High ice concentration (and 'area') were at the core of my 'high' projection, and I'm starting to feel a bit concerned now that we may see a lot more ice disappear rather than preserved before the end of the season....

EgalSust

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Re: 2017 sea ice area and extent data
« Reply #380 on: August 03, 2017, 02:51:04 PM »
NSIDC extent down 100k:

2017,    08,  01,      6.460
2017,    08,  02,      6.358

Running a couple hundred thousand behind 2012:

2012,    08,  01,      6.255
2012,    08,  02,      6.152

Wipneus

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Re: 2017 sea ice area and extent data
« Reply #381 on: August 03, 2017, 07:02:06 PM »
Peculiar differences with UH AMSR2 today. NSIDC sees most of the drop in Kara, none in the CAB (a plus actually).

Regional Arctic Sea Ice Extent and Area calculated from NSIDC NASA Team concentration data
Date: 2017-08-02 12:00  Values in 1000 km^2

Extent (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  4375.1  +18.0   -26.3    260.5  -12.8  -431.3    322.7  -20.5  -125.0
               Kara Sea             Barents Sea           Greenland Sea
   162.1  -62.2  -279.1     34.6   -8.5   -65.4    191.4   +5.2  -140.8
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
   191.6  +35.1    -7.8      0.0   +0.0    +0.0     93.2  -19.6   -98.7
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   506.3  -27.7   -89.0    151.4   -0.6  -198.6     35.2   -6.3  -215.3
             Bering Sea          Sea of Okhotsk                   Lakes
     4.1   -0.1    +4.1     17.4   -2.8   +17.4    158.7  +11.1   +30.4
          Other regions       Total (ex. lakes)
    12.5   +0.6   +12.5   6358.1 -102.4 -1643.5

Area (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  3253.5  -51.5  -401.7    137.6   -1.7  -290.8    203.1  -10.1   -60.1
               Kara Sea             Barents Sea           Greenland Sea
    64.8  -22.5  -184.2      9.5   -2.4   -32.0     77.0   +4.8   -78.0
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
    67.8  +11.4   -11.7      0.0   +0.0    +0.0     27.1   -6.3   -46.8
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   311.9  -15.7   -52.3     79.6  -16.2  -129.1      9.3   -1.4  -124.1
             Bering Sea          Sea of Okhotsk                   Lakes
     0.9   +0.1    +0.9      5.3   -0.9    +5.3     89.9   +2.5   +33.4
          Other regions       Total (ex. lakes)
     7.8   -0.5    +7.8   4255.0 -112.9 -1396.8


Delta map attached: red/blue means the concentration went below/over the 15% cut-off. Reddish/bluish means the concentration decreased/increased by more than 7%.

Wipneus

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Re: 2017 sea ice area and extent data
« Reply #382 on: August 04, 2017, 06:12:12 PM »
Nearly a century extent drop, mostly caused by the Baffin region. CAB area had a regional century increase.

Regional Arctic Sea Ice Extent and Area calculated from NSIDC NASA Team concentration data
Date: 2017-08-03 12:00  Values in 1000 km^2

Extent (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  4374.5   -0.7   -25.3    242.6  -17.9  -436.8    316.8   -5.9  -123.6
               Kara Sea             Barents Sea           Greenland Sea
   156.9   -5.2  -273.7     43.7   +9.1   -52.0    174.5  -16.9  -153.3
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
   146.7  -44.9   -49.0      0.0   +0.0    +0.0     74.4  -18.8  -112.1
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   511.7   +5.4   -78.5    151.4   -0.0  -198.9     34.6   -0.6  -212.1
             Bering Sea          Sea of Okhotsk                   Lakes
     1.7   -2.4    +1.7     19.1   +1.7   +19.1    150.0   -9.2   +21.1
          Other regions       Total (ex. lakes)
    11.8   -0.6   +11.8   6260.3  -97.8 -1682.7

Area (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  3355.8 +102.3  -293.2    121.7  -15.9  -301.9    183.5  -19.6   -74.0
               Kara Sea             Barents Sea           Greenland Sea
    62.1   -2.7  -179.7     13.5   +4.0   -26.1     68.6   -8.4   -84.9
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
    54.1  -13.7   -23.0      0.0   +0.0    +0.0     24.0   -3.1   -47.7
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   300.6  -11.2   -56.7     79.3   -0.3  -125.9      8.4   -0.9  -121.5
             Bering Sea          Sea of Okhotsk                   Lakes
     0.4   -0.4    +0.4      6.2   +0.9    +6.2     91.9   +1.9   +34.7
          Other regions       Total (ex. lakes)
     8.6   +0.8    +8.6   4286.8  +31.8 -1319.5


Delta map attached: red/blue means the concentration went below/over the 15% cut-off. Reddish/bluish means the concentration decreased/increased by more than 7%.

Wipneus

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Re: 2017 sea ice area and extent data
« Reply #383 on: August 04, 2017, 06:15:43 PM »
Updates of the basin-only graphs.

Shared Humanity

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Re: 2017 sea ice area and extent data
« Reply #384 on: August 04, 2017, 09:03:10 PM »
That latest image highlights a persistent feature of this melt season, nonexistent transport through the Fram. This has played a major role in the slow decline in SIE and SIA.

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Re: 2017 sea ice area and extent data
« Reply #385 on: August 05, 2017, 04:16:47 PM »
Another century extent drop, much of it coming from the ESS and its neighbors.

Regional Arctic Sea Ice Extent and Area calculated from NSIDC NASA Team concentration data
Date: 2017-08-04 12:00  Values in 1000 km^2

Extent (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  4358.3  -16.2   -38.2    207.3  -35.3  -464.5    299.5  -17.3  -128.7
               Kara Sea             Barents Sea           Greenland Sea
   146.5  -10.4  -274.8     37.2   -6.5   -54.0    169.3   -5.2  -153.9
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
   134.2  -12.5   -53.5      0.0   +0.0    +0.0     61.0  -13.4  -121.1
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   489.2  -22.5   -96.5    155.1   +3.7  -195.6     25.0   -9.6  -214.5
             Bering Sea          Sea of Okhotsk                   Lakes
     4.1   +2.4    +4.1     17.9   -1.1   +17.9    167.7  +17.7   +35.2
          Other regions       Total (ex. lakes)
    13.0   +1.1   +13.0   6117.5 -142.8 -1760.4

Area (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  3329.0  -26.8  -307.1    109.6  -12.1  -307.0    176.0   -7.5   -77.2
               Kara Sea             Barents Sea           Greenland Sea
    55.4   -6.6  -180.2     12.0   -1.5   -25.4     68.3   -0.3   -82.1
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
    47.4   -6.7   -26.6      0.0   +0.0    +0.0     19.7   -4.3   -49.9
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   300.7   +0.1   -49.1     77.9   -1.4  -125.3      5.9   -2.5  -118.8
             Bering Sea          Sea of Okhotsk                   Lakes
     0.8   +0.4    +0.8      5.8   -0.5    +5.8     98.7   +6.8   +39.8
          Other regions       Total (ex. lakes)
     8.7   +0.1    +8.7   4217.2  -69.6 -1333.4


Delta map attached: red/blue means the concentration went below/over the 15% cut-off. Reddish/bluish means the concentration decreased/increased by more than 7%.

BornFromTheVoid

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Re: 2017 sea ice area and extent data
« Reply #386 on: August 06, 2017, 07:18:01 PM »
Update for the week to August 5th

The current 5 day trailing average is on 6,268,000km2 while the 1 day extent is at 6,146,000km2.

(All the following data is based on a trailing 5 day average)
The daily anomaly (compared to 81-10) is at -1,679,000km2, an increase from -1,540,000km2 last week. The anomaly compared to the 07, 11 and 12 average is at +7,000km2, a decrease from +205,000km2 last week. We're currently 3rd lowest on record, up from 4th lowest last week.



The average daily change over the last 7 days was -101.3k/day, compared to the long term average of -81.5k/day, and the 07, 11 and 12 average of -73.0k/day.
The average long term change over the next week is -67.1k/day, with the 07, 11, and 12 average being -104.1k/day.



The extent loss so far this August is the 3rd largest on record. To achieve the largest loss, a drop of at least 86.2k/day is required (more than 88.3k/day with single day values), while the smallest loss requires a drop of less than 27.3k/day (less than 24.3k/day with single day values) and an average loss requires a drop of 47.8k/day (46.7k/day with single day values).



The extent loss in July was the 15th largest on record while the average extent was the 4th smallest on record.




Wipneus

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Re: 2017 sea ice area and extent data
« Reply #387 on: August 07, 2017, 05:38:04 PM »
The sea ice concentration products agree (for one day): most of area and extent losses are found in the CAB on the side of the Beaufort and Chukchi.

Regional Arctic Sea Ice Extent and Area calculated from NSIDC NASA Team concentration data
Date: 2017-08-06 12:00  Values in 1000 km^2

Extent (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  4319.0  -29.0   -74.3    190.6  -19.9  -459.3    271.4   -5.1  -141.0
               Kara Sea             Barents Sea           Greenland Sea
   170.4  +13.3  -234.8     37.1   -0.0   -49.1    155.7  -11.7  -155.6
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
   149.8  -10.8   -21.8      0.0   +0.0    +0.0     66.2   +2.2   -99.4
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   523.8  +14.1   -46.4    151.9   -8.2  -193.3      8.3  -10.2  -220.4
             Bering Sea          Sea of Okhotsk                   Lakes
     2.9   -1.8    +2.9     16.3   -3.3   +16.3    182.3  -10.7   +41.8
          Other regions       Total (ex. lakes)
    11.8   +0.0   +11.8   6075.3  -70.5 -1664.3

Area (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  3138.7  -98.0  -495.8     89.7   -9.6  -309.5    174.7  +12.5   -71.2
               Kara Sea             Barents Sea           Greenland Sea
    68.1   +3.9  -161.3     13.7   +1.5   -21.6     60.3   -3.4   -83.9
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
    54.0   -2.7   -13.8      0.0   +0.0    +0.0     21.6   +0.9   -39.9
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   318.0   +7.6   -16.9     77.9   -9.8  -121.2      1.6   -2.3  -116.3
             Bering Sea          Sea of Okhotsk                   Lakes
     0.8   -0.2    +0.8      5.5   -1.4    +5.5     96.6   -4.9   +34.8
          Other regions       Total (ex. lakes)
     8.3   +0.1    +8.3   4032.7 -100.5 -1436.8


Delta map attached: red/blue means the concentration went below/over the 15% cut-off. Reddish/bluish means the concentration decreased/increased by more than 7%.

Wipneus

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Re: 2017 sea ice area and extent data
« Reply #388 on: August 08, 2017, 02:27:35 PM »
Extent is being lost in a wide Beaufort/Chukchi bite. Area not so much.

Regional Arctic Sea Ice Extent and Area calculated from NSIDC NASA Team concentration data
Date: 2017-08-07 12:00  Values in 1000 km^2

Extent (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  4273.8  -45.3  -117.6    181.6   -9.0  -455.8    272.0   +0.7  -133.0
               Kara Sea             Barents Sea           Greenland Sea
   177.6   +7.2  -220.9     32.0   -5.0   -50.8    149.8   -5.8  -155.8
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
   146.1   -3.8   -13.3      0.0   +0.0    +0.0     54.1  -12.1  -102.3
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   518.8   -5.0   -44.9    148.1   -3.8  -194.0      5.7   -2.6  -216.4
             Bering Sea          Sea of Okhotsk                   Lakes
     4.1   +1.2    +4.1     17.5   +1.2   +17.5    172.9   -9.9   +34.5
          Other regions       Total (ex. lakes)
    13.0   +1.1   +13.0   5994.3  -81.0 -1670.0

Area (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  3147.9   +9.2  -497.6     90.5   +0.8  -297.8    174.1   -0.6   -64.4
               Kara Sea             Barents Sea           Greenland Sea
    73.4   +5.3  -147.3     10.9   -2.8   -22.9     56.9   -3.4   -83.2
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
    50.5   -3.5   -12.4      0.0   +0.0    +0.0     15.6   -6.0   -42.2
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   307.5  -10.5   -22.4     80.6   +2.7  -114.7      1.1   -0.5  -113.4
             Bering Sea          Sea of Okhotsk                   Lakes
     1.0   +0.3    +1.0      7.3   +1.8    +7.3     91.5   -5.2   +29.9
          Other regions       Total (ex. lakes)
     9.0   +0.7    +9.0   4026.2   -6.5 -1401.2


Delta map attached: red/blue means the concentration went below/over the 15% cut-off. Reddish/bluish means the concentration decreased/increased by more than 7%.

Wipneus

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Re: 2017 sea ice area and extent data
« Reply #389 on: August 09, 2017, 06:27:34 PM »
A century extent drop, about half outside the basin: CAA. Baffin, Greenland Sea.
Area actually increased a bit.

Regional Arctic Sea Ice Extent and Area calculated from NSIDC NASA Team concentration data
Date: 2017-08-08 12:00  Values in 1000 km^2

Extent (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  4258.2  -15.6  -129.1    174.1   -7.6  -459.6    268.9   -3.1  -126.5
               Kara Sea             Barents Sea           Greenland Sea
   174.1   -3.5  -216.6     27.5   -4.6   -51.6    138.1  -11.8  -161.5
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
   120.7  -25.4   -32.7      0.0   +0.0    +0.0     54.5   +0.4   -99.1
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   498.0  -20.8   -65.0    139.2   -8.9  -196.8      4.5   -1.2  -213.6
             Bering Sea          Sea of Okhotsk                   Lakes
     4.0   -0.0    +4.0     15.2   -2.3   +15.2    179.2   +6.2   +44.0
          Other regions       Total (ex. lakes)
    13.4   +0.5   +13.4   5890.3 -103.9 -1719.3

Area (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  3169.6  +21.7  -466.7     93.7   +3.2  -285.4    175.3   +1.2   -58.3
               Kara Sea             Barents Sea           Greenland Sea
    77.6   +4.2  -140.2      9.7   -1.2   -22.2     54.8   -2.1   -82.0
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
    41.1   -9.3   -19.2      0.0   +0.0    +0.0     16.1   +0.4   -39.6
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   308.8   +1.3   -20.5     70.6  -10.1  -118.4      1.0   -0.1  -109.3
             Bering Sea          Sea of Okhotsk                   Lakes
     0.8   -0.2    +0.8      6.0   -1.3    +6.0     96.0   +4.5   +36.3
          Other regions       Total (ex. lakes)
     8.8   -0.1    +8.8   4033.8   +7.7 -1346.1


Delta map attached: red/blue means the concentration went below/over the 15% cut-off. Reddish/bluish means the concentration decreased/increased by more than 7%.

Wipneus

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Re: 2017 sea ice area and extent data
« Reply #390 on: August 10, 2017, 06:29:39 PM »
Same as the past few days. Extent is lost mainly along the ice edge facing Beaufort and Chukchi.

Regional Arctic Sea Ice Extent and Area calculated from NSIDC NASA Team concentration data
Date: 2017-08-09 12:00  Values in 1000 km^2

Extent (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  4193.6  -64.6  -189.8    181.6   +7.5  -445.6    270.2   +1.3  -110.1
               Kara Sea             Barents Sea           Greenland Sea
   159.7  -14.4  -220.9     26.8   -0.6   -51.6    131.5   -6.6  -162.1
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
   100.3  -20.4   -49.2      0.0   +0.0    +0.0     53.2   -1.3   -93.5
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   501.0   +3.0   -49.9    143.0   +3.8  -188.6      0.6   -3.8  -213.9
             Bering Sea          Sea of Okhotsk                   Lakes
     4.7   +0.7    +4.7     18.6   +3.4   +18.6    176.8   -2.4   +46.1
          Other regions       Total (ex. lakes)
    12.3   -1.1   +12.3   5797.1  -93.2 -1739.5

Area (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  3144.0  -25.6  -494.0     88.2   -5.4  -284.2    184.5   +9.2   -43.7
               Kara Sea             Barents Sea           Greenland Sea
    67.5  -10.1  -146.3     10.0   +0.3   -21.4     52.7   -2.1   -83.1
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
    34.7   -6.4   -24.7      0.0   +0.0    +0.0     17.1   +1.0   -35.5
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   298.1  -10.7   -27.3     78.8   +8.2  -107.4      0.5   -0.5  -107.3
             Bering Sea          Sea of Okhotsk                   Lakes
     0.9   +0.1    +0.9      6.1   +0.1    +6.1     99.8   +3.8   +40.7
          Other regions       Total (ex. lakes)
     8.7   -0.1    +8.7   3991.7  -42.1 -1359.2


Delta map attached: red/blue means the concentration went below/over the 15% cut-off. Reddish/bluish means the concentration decreased/increased by more than 7%.

CalamityCountdown

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Re: 2017 sea ice area and extent data
« Reply #391 on: August 10, 2017, 08:58:25 PM »
Based on NSIDC reports, the daily extent has bounced around from 2nd to 4th lowest in their records over the last few days. Would not be terribly surprising if it continued to do so for the remainder of the melt season.

Shared Humanity

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Re: 2017 sea ice area and extent data
« Reply #392 on: August 10, 2017, 09:59:14 PM »
Based on NSIDC reports, the daily extent has bounced around from 2nd to 4th lowest in their records over the last few days. Would not be terribly surprising if it continued to do so for the remainder of the melt season.

Yep.

Wipneus

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Re: 2017 sea ice area and extent data
« Reply #393 on: August 11, 2017, 06:15:06 PM »
Extent drops in the same place again. The area drop is significant.

Regional Arctic Sea Ice Extent and Area calculated from NSIDC NASA Team concentration data
Date: 2017-08-10 12:00  Values in 1000 km^2

Extent (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  4144.3  -49.3  -235.0    182.9   +1.3  -432.9    272.2   +1.9  -106.4
               Kara Sea             Barents Sea           Greenland Sea
   151.9   -7.8  -218.7     33.8   +7.0   -40.9    117.9  -13.5  -168.9
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
   104.8   +4.6   -34.6      0.0   +0.0    +0.0     47.0   -6.2   -91.9
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   487.9  -13.1   -55.1    133.5   -9.5  -195.9      0.6   +0.0  -207.6
             Bering Sea          Sea of Okhotsk                   Lakes
     4.7   -0.0    +4.7     11.2   -7.4   +11.2    163.0  -14.3   +32.1
          Other regions       Total (ex. lakes)
    14.4   +2.1   +14.4   5707.1  -90.0 -1757.5

Area (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  3038.4 -105.6  -595.3     93.0   +4.7  -275.2    191.8   +7.3   -32.5
               Kara Sea             Barents Sea           Greenland Sea
    65.6   -1.9  -144.8     10.4   +0.3   -19.6     44.4   -8.3   -88.6
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
    35.3   +0.6   -20.3      0.0   +0.0    +0.0     15.3   -1.7   -33.9
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   281.8  -16.4   -36.9     65.6  -13.2  -117.7      0.1   -0.3  -104.7
             Bering Sea          Sea of Okhotsk                   Lakes
     1.2   +0.3    +1.2      2.6   -3.4    +2.6     99.9   +0.1   +42.8
          Other regions       Total (ex. lakes)
     9.1   +0.4    +9.1   3854.6 -137.1 -1456.5


Delta map attached: red/blue means the concentration went below/over the 15% cut-off. Reddish/bluish means the concentration decreased/increased by more than 7%.

Over the CAB crescent-like  shaped area of concentration drops can be seen. In attached nullschool image, you can see it neatly matches a similar shaped area with precipitation.

Jim Pettit

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Re: 2017 sea ice area and extent data
« Reply #394 on: August 12, 2017, 02:17:10 PM »
NSIDC extent is back in second place (barely) after another century-plus drop:



With four-five weeks or so left in the melt season, 2017 extent is now below every minimum recorded from 1979-2004, along with 2006.

The extent projector suggest 2017 should bottom out around 4.2M km2, and see a September average of 4.3M:



Side note: I haven't seen whether the change is permanent, but the daily NSIDC data seems to have moved from:

OLD URL: ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/north/daily/data/N_seaice_extent_daily_v2.1.csv+AO219

To...

NEW URL: ftp://sidads.colorado.edu/pub/DATASETS/NOAA/G02135/north/daily/data/N_seaice_extent_daily_v2.1.csv

Wipneus

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Re: 2017 sea ice area and extent data
« Reply #395 on: August 12, 2017, 06:03:18 PM »
As noted a century extent drop and one for area as well. The CAB/Beaufort sea ice loss continues. Big changes in the CAA and Kara as well, but look like noise and mostly cancel each other in the net figures.

Regional Arctic Sea Ice Extent and Area calculated from NSIDC NASA Team concentration data
Date: 2017-08-11 12:00  Values in 1000 km^2

Extent (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  4099.5  -44.8  -277.1    185.5   +2.6  -425.4    273.4   +1.3   -99.0
               Kara Sea             Barents Sea           Greenland Sea
   183.2  +31.3  -179.7     22.2  -11.6   -49.8    110.3   -7.7  -175.3
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
    85.0  -19.9   -44.7      0.0   +0.0    +0.0     31.4  -15.6  -105.4
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   431.6  -56.2  -104.6    110.0  -23.5  -218.0      8.7   +8.1  -193.6
             Bering Sea          Sea of Okhotsk                   Lakes
     8.3   +3.6    +8.3     17.9   +6.7   +17.9    141.8  -21.1   +11.3
          Other regions       Total (ex. lakes)
    15.1   +0.6   +15.1   5582.1 -125.1 -1831.3

Area (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  2966.3  -72.1  -642.6     93.0   +0.0  -275.8    189.1   -2.7   -30.6
               Kara Sea             Barents Sea           Greenland Sea
    76.0  +10.4  -127.9      7.3   -3.1   -21.6     41.2   -3.2   -90.5
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
    31.7   -3.6   -20.3      0.0   +0.0    +0.0      9.7   -5.6   -38.3
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   263.9  -17.9   -49.7     58.6   -7.0  -121.5      1.9   +1.8   -99.9
             Bering Sea          Sea of Okhotsk                   Lakes
     1.9   +0.7    +1.9      5.4   +2.7    +5.4     83.7  -16.1   +26.9
          Other regions       Total (ex. lakes)
     8.5   -0.7    +8.5   3754.4 -100.3 -1502.8


Delta map attached: red/blue means the concentration went below/over the 15% cut-off. Reddish/bluish means the concentration decreased/increased by more than 7%.

Wipneus

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Re: 2017 sea ice area and extent data
« Reply #396 on: August 12, 2017, 06:13:49 PM »
Update of the Basin-only graphs of NSIDC derived extent and area.

Assuming that going lower than 2012 will not happen, several other possibilities are still open.

Tor Bejnar

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Re: 2017 sea ice area and extent data
« Reply #397 on: August 12, 2017, 09:21:35 PM »
"Anything can still happen."  (I don't know who I'm quoting!)  Per the NSIDC graph, 2017 is approximately where 2013 was 'today', and 2013 all but 'caught up to' 2012 at one point later in the season.  Although statistically unlikely, there remains a (convoluted) path towards a record melt.  (I'm not holding my breath.)
Arctic ice is healthy for children and other living things.

Csnavywx

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Re: 2017 sea ice area and extent data
« Reply #398 on: August 13, 2017, 05:25:57 PM »
Might have a slowdown for a day or two before the big torch hits and lights a fire under the metrics.

Wipneus

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Re: 2017 sea ice area and extent data
« Reply #399 on: August 13, 2017, 06:16:43 PM »
NSIDC sea ice concentration looses extent in the CAA, Kara and Laptev. The CAA has lost over a century in two days.

Regional Arctic Sea Ice Extent and Area calculated from NSIDC NASA Team concentration data
Date: 2017-08-12 12:00  Values in 1000 km^2

Extent (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  4090.4   -9.1  -282.1    184.8   -0.7  -417.1    246.2  -27.2  -119.9
               Kara Sea             Barents Sea           Greenland Sea
   132.7  -50.5  -217.9     15.0   -7.2   -53.7    121.4  +11.1  -158.9
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
    86.0   +1.0   -39.8      0.0   +0.0    +0.0     37.2   +5.9   -97.7
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   381.3  -50.4  -152.7    117.0   +6.9  -206.5      3.7   -5.0  -195.4
             Bering Sea          Sea of Okhotsk                   Lakes
     4.7   -3.6    +4.7     19.1   +1.3   +19.1    155.8  +13.0   +25.5
          Other regions       Total (ex. lakes)
    17.4   +2.4   +17.4   5456.9 -125.2 -1900.4

Area (value, one day change, anomaly):
   Central Arctic Basin       East Siberian Sea              Laptev Sea
  2956.5   -9.8  -644.6     95.8   +2.8  -270.1    183.2   -5.8   -31.0
               Kara Sea             Barents Sea           Greenland Sea
    57.4  -18.6  -139.2      4.7   -2.6   -23.0     47.3   +6.1   -82.0
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
    30.8   -0.9   -20.6      0.0   +0.0    +0.0     12.2   +2.5   -35.7
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
   241.2  -22.7   -67.4     57.7   -0.8  -120.0      1.3   -0.6   -99.2
             Bering Sea          Sea of Okhotsk                   Lakes
     1.0   -0.9    +1.0      5.7   +0.4    +5.7     87.8   +3.9   +30.4
          Other regions       Total (ex. lakes)
    10.4   +1.9   +10.4   3705.2  -49.2 -1515.7


Delta map attached: red/blue means the concentration went below/over the 15% cut-off. Reddish/bluish means the concentration decreased/increased by more than 7%.