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Click on the dates or types to select other images. Clicking on an already selected date or type enables hover mode. Then the images will switch on mouse movements, but be patient the first time an image loads (or preload them first). Clicking on the image steps to the next date or stops a running animation. Data are from the Global Data Assimilation System (GDAS). Current data are available at ftpprd.ncep.noaa.gov, an incomplete archive is at NOMADS. Note that this model is intended to be used as initialization in numerical weather predictions and isn't a specialized ice model. Ice concentration is based on the NCEP sea ice analysis, thickness is modeled based on analyzed surface fluxes and presumably doesn't contain any real measurements. The model doesn't account for ice movements. Some notes on the current (?) GFS/GDAS sea ice model are here. Due to model changes, the data aren't necessarily consistent over time. A change in ice thickness that cannot be explained by normal model operation has occurred on 2007-12-04 (images: Arctic, Antarctic; note that the displayed changes are from one model cycle to the other (6 hours) and not changes within 24 hours as in the other images), another on 2008-09-17 (Arctic, Antarctic). There may be more. I don't know the reason. Occasionally, ice thickness is reset to zero because of erroneous ice concentration data. You can see a stark example in the 2008-04-03 images. The modeled ice thickness still hasn't recovered completely half a year later. The sea surface height in the model can be substantially above or below normal sea level near coasts. This is due to the use of spherical harmonics, which cannot describe a totally flat surface or abrupt changes in gradient and have lower resolution than the grid cells used to calculate surface values (you can estimate the effective T382 resolution by the moiré-like patterns in the orography). Together with spurious coastal ice, this may contribute to anomalous ice thickness values. The values below are calculated with
GrADS' Modeled ice thickness seems to be always zero where ice concentration
is below 25 %.
The 3 values for average thickness refer to ice extent
( |
Extent / 10³ km² Area / 10³ km² Area+ / 10³ km² Volume / km³ ThickE / cm ThickA / cm ThickT / cm Date NH SH Gl NH SH Gl NH SH Gl NH SH Gl NH SH Gl NH SH Gl NH SH Gl 2007-03-06 12Z: 15042 3020 18062 13263 2378 15641 13291 2386 15677 16647 2304 18951 111 76 105 125 97 121 127 99 123 2007-03-10 12Z: 15367 3248 18616 13395 2583 15978 13422 2592 16014 16900 2388 19288 110 74 104 126 92 120 128 94 123 2007-03-15 12Z: 15124 3541 18664 13244 2862 16106 13270 2870 16140 17120 2496 19616 113 71 105 129 87 122 131 88 124 2007-03-20 12Z: 14872 3744 18617 13032 3049 16081 13059 3058 16117 17258 2604 19862 116 70 107 132 85 123 135 87 125 2007-03-25 12Z: 14926 3986 18912 13068 3283 16351 13093 3291 16384 17399 2709 20109 117 68 106 133 82 123 135 84 125 2007-03-30 00Z: 14462 4367 18829 12606 3584 16190 12632 3592 16224 17413 2872 20285 120 66 108 138 80 125 140 81 127 2007-04-04 12Z: 14557 4753 19310 12701 3956 16658 12727 3965 16692 17548 3065 20613 121 64 107 138 77 123 140 78 125 2007-04-09 12Z: 14276 5312 19588 12499 4445 16943 12523 4453 16976 17416 3305 20721 122 62 106 139 74 122 141 75 124 2007-04-14 12Z: 14256 5831 20087 12572 4925 17496 12594 4932 17527 17554 3569 21124 123 61 105 139 72 121 142 73 122 2007-04-19 12Z: 13987 6432 20419 12271 5531 17802 12294 5539 17832 17404 3888 21292 124 60 104 142 70 119 144 71 121 2007-04-24 12Z: 13686 7001 20687 12044 6008 18052 12067 6016 18083 17390 4173 21563 127 60 104 144 69 119 146 70 121 2007-04-29 12Z: 13585 7474 21059 11993 6438 18431 12014 6447 18461 17435 4463 21899 128 60 104 145 69 119 147 70 120 2007-05-04 12Z: 13441 7758 21199 11905 6676 18582 11925 6686 18612 17317 4596 21914 129 59 103 145 69 118 148 69 119 2007-05-10 00Z: 13138 8320 21458 11644 7342 18986 11664 7352 19015 17203 5019 22222 131 60 104 147 68 117 150 69 118 2007-05-14 12Z: 12873 9005 21878 11358 7998 19356 11377 8006 19383 16974 5382 22356 132 60 102 149 67 115 152 68 117 2007-05-20 06Z: 12744 9566 22310 11177 8475 19653 11196 8484 19680 16794 5737 22531 132 60 101 150 68 114 152 68 116 2007-05-24 12Z: 12422 10208 22630 10844 9011 19855 10864 9019 19883 16508 6104 22612 133 60 100 152 68 114 154 68 115 2007-05-29 12Z: 12187 10691 22878 10654 9538 20193 10674 9547 20222 16201 6471 22673 133 61 99 152 68 112 154 68 113 2007-06-03 12Z: 11981 11533 23514 10424 10260 20683 10444 10268 20713 15735 6937 22672 131 60 96 151 68 109 153 68 111 2007-06-08 12Z: 11727 11964 23690 9919 10652 20570 9939 10661 20600 14757 7286 22043 126 61 93 148 68 107 151 69 108 2007-06-16 00Z: 10528 12813 23342 8634 11378 20012 8654 11386 20040 13098 7809 20907 124 61 90 151 69 104 154 69 105 2007-06-19 12Z: 10444 13362 23806 8496 12013 20509 8519 12022 20542 12369 8233 20602 118 62 87 145 68 100 148 69 101 2007-06-25 00Z: 9515 13806 23321 7743 12478 20221 7764 12487 20251 11187 8739 19926 118 63 85 144 70 98 147 70 99 2007-06-28 12Z: 8994 13996 22990 7394 12691 20085 7413 12700 20112 10506 9031 19536 117 65 85 142 71 97 144 71 98 2007-07-04 00Z: 8585 14577 23162 6915 13176 20091 6934 13184 20118 9457 9425 18882 110 65 82 136 71 94 139 72 95 2007-07-08 12Z: 8029 14748 22777 6532 13221 19753 6548 13231 19778 8809 9703 18512 110 66 81 135 73 94 137 74 94 2007-07-13 12Z: 7363 15080 22442 5884 13608 19492 5899 13618 19517 8016 10124 18139 109 67 81 136 74 93 138 75 94 2007-07-19 00Z: 6540 15630 22170 5127 14072 19198 5145 14083 19227 7016 10586 17602 107 68 79 136 75 92 139 76 92 2007-07-23 12Z: 6309 16189 22498 4918 14677 19594 4934 14687 19621 6437 11101 17539 102 69 78 130 76 89 133 76 90 2007-07-27 18Z: 5568 16528 22096 4431 14830 19262 4445 14842 19287 6097 11386 17482 109 69 79 137 77 91 140 77 91 2007-08-02 12Z: 5497 16830 22327 4320 15133 19453 4333 15144 19477 5842 11904 17745 106 71 79 135 79 91 137 79 92 2007-08-07 12Z: 5262 16849 22110 4140 15147 19287 4152 15158 19311 5553 12197 17750 106 72 80 134 80 92 136 81 93 2007-08-12 12Z: 4734 17197 21930 3730 15410 19140 3743 15420 19162 5283 12520 17803 112 73 81 141 81 93 144 82 94 2007-08-17 12Z: 4345 16990 21335 3384 15335 18720 3396 15344 18740 4970 12862 17832 114 76 84 146 84 95 149 84 96 2007-08-22 12Z: 4188 17183 21371 3266 15556 18822 3276 15565 18842 4802 13231 18034 115 77 84 147 85 96 149 85 96 2007-08-27 12Z: 4166 17718 21883 3350 16059 19408 3359 16067 19427 4876 13639 18515 117 77 85 145 85 95 148 85 96 2007-09-01 12Z: 3845 18046 21891 3157 16388 19546 3165 16399 19564 4750 14128 18878 124 78 86 150 86 96 152 87 97 2007-09-07 00Z: 3593 18371 21964 2952 16692 19644 2960 16701 19661 4525 14570 19094 126 79 87 153 87 97 155 88 98 2007-09-11 12Z: 3640 18351 21991 3084 16775 19860 3091 16786 19878 4625 14876 19501 127 81 89 150 89 98 152 89 99 2007-09-16 12Z: 3689 18524 22213 3109 16883 19991 3116 16893 20009 4557 15153 19710 124 82 89 146 90 99 149 90 99 2007-09-21 12Z: 3830 18550 22380 3188 16984 20172 3196 16994 20190 4566 15502 20068 119 84 90 143 91 99 145 92 100 2007-09-26 12Z: 3817 18586 22404 3177 16950 20128 3184 16960 20144 4569 15714 20283 120 85 91 143 93 101 146 93 101 2007-10-01 12Z: 4175 18548 22724 3574 16901 20476 3582 16911 20493 4790 15895 20685 115 86 91 134 94 101 136 94 102 2007-10-06 12Z: 4488 18367 22856 3786 16579 20365 3794 16588 20382 4926 15948 20874 110 87 91 130 96 102 132 97 103 2007-10-11 12Z: 5008 18126 23134 4173 16270 20442 4185 16279 20464 5096 15992 21088 102 88 91 122 98 103 124 99 104 2007-10-16 12Z: 5403 18336 23739 4542 16409 20951 4554 16419 20972 5249 16188 21437 97 88 90 115 99 102 117 99 103 2007-10-21 12Z: 5744 17904 23647 4838 16151 20989 4851 16161 21011 5432 16407 21839 95 92 92 112 102 104 114 102 105 2007-10-26 12Z: 7038 17819 24858 5837 16051 21889 5853 16062 21915 5725 16173 21897 81 91 88 98 101 100 100 101 101 2007-10-31 12Z: 8220 17306 25526 6962 15320 22282 6977 15332 22309 6195 15864 22059 75 92 86 89 103 99 90 104 100 2007-11-05 12Z: 9039 16754 25794 7885 14836 22721 7900 14846 22747 6662 15708 22371 74 94 87 84 106 98 86 106 99 2007-11-10 12Z: 9650 16164 25814 8376 14198 22574 8392 14208 22600 7072 15312 22384 73 95 87 84 108 99 86 108 100 2007-11-15 12Z: 10108 15366 25474 8811 13625 22436 8827 13636 22464 7465 15047 22512 74 98 88 85 110 100 86 111 101 2007-11-20 12Z: 10398 14816 25214 8960 13073 22033 8977 13084 22061 7787 14606 22394 75 99 89 87 112 102 88 112 103 2007-11-25 12Z: 10646 14078 24724 9217 12395 21613 9235 12407 21642 8103 14137 22240 76 100 90 88 114 103 89 115 104 2007-11-30 12Z: 11064 13637 24702 9631 11852 21483 9651 11864 21516 8535 13663 22198 77 100 90 88 115 103 90 116 104 2007-12-06 00Z: 11424 13059 24483 9834 11350 21184 9855 11360 21216 8757 13407 22164 77 103 91 89 118 104 90 119 106 2007-12-11 18Z: 12024 12430 24454 10496 10485 20981 10515 10496 21012 9316 12462 21778 77 100 89 89 119 104 90 119 105 2007-12-15 18Z: 12323 11861 24184 10767 9861 20628 10788 9875 20663 9598 11707 21306 78 99 88 89 119 103 90 119 104 2007-12-20 12Z: 12721 11124 23845 11228 9155 20383 11249 9169 20418 10091 10935 21026 79 98 88 90 119 103 91 120 104 2007-12-25 12Z: 13142 9915 23057 11478 8022 19500 11501 8037 19538 10545 9728 20274 80 98 88 92 121 104 93 122 105 2007-12-30 12Z: 13444 8798 22241 11722 7086 18808 11746 7101 18848 11023 8664 19686 82 98 89 94 122 104 95 123 106 2008-01-04 12Z: 13737 7744 21481 11954 6045 17999 11978 6060 18039 11414 7509 18924 83 97 88 95 124 105 97 126 107 2008-01-09 12Z: 13864 6903 20766 12067 5368 17435 12090 5382 17472 11891 6701 18592 86 97 90 98 124 106 100 126 108 2008-01-14 12Z: 14331 5889 20220 12493 4494 16986 12518 4508 17026 12399 5754 18153 87 98 90 99 128 107 101 130 109 2008-01-19 12Z: 14326 5079 19404 12374 3872 16246 12400 3887 16287 12658 5002 17660 88 98 91 102 129 108 104 131 110 2008-01-24 12Z: 14857 4395 19252 12831 3415 16246 12858 3428 16287 13164 4528 17693 89 103 92 102 132 109 104 135 111 2008-01-29 12Z: 14646 3958 18604 12715 3026 15741 12740 3038 15777 13430 4026 17457 92 102 94 105 133 111 107 136 113 2008-02-03 12Z: 15068 3521 18589 12945 2771 15716 12971 2782 15752 13738 3748 17487 91 106 94 106 135 111 108 138 113 2008-02-08 12Z: 15265 3419 18684 13180 2680 15860 13206 2691 15896 14155 3594 17748 93 105 95 107 134 112 109 137 114 2008-02-13 12Z: 15607 3241 18848 13409 2533 15942 13436 2542 15978 14510 3413 17923 93 105 95 108 134 112 110 137 114 2008-02-18 12Z: 15102 3307 18409 12983 2538 15521 13011 2548 15559 14664 3309 17973 97 100 98 113 130 116 115 133 118 2008-02-23 18Z: 15554 3333 18887 13485 2567 16052 13512 2577 16090 15188 3279 18466 98 98 98 112 127 115 114 130 117 2008-02-28 12Z: 15648 3625 19273 13528 2776 16304 13554 2786 16341 15454 3315 18769 99 91 97 114 119 115 116 122 117 2008-03-04 12Z: 15423 4008 19430 13410 3193 16602 13435 3201 16636 15712 3473 19185 102 87 99 117 109 115 119 110 117 2008-03-09 12Z: 15669 4344 20013 13691 3476 17167 13717 3485 17202 15997 3589 19586 102 83 98 117 103 114 119 105 116 2008-03-14 12Z: 15648 4632 20281 13610 3847 17456 13636 3855 17491 16206 3781 19987 104 82 99 119 98 114 121 99 116 2008-03-19 12Z: 15635 5170 20805 13578 4356 17934 13604 4365 17969 16455 4003 20459 105 77 98 121 92 114 123 93 116 2008-03-24 12Z: 15592 5602 21195 13563 4669 18232 13588 4677 18265 16675 4155 20830 107 74 98 123 89 114 125 90 116 2008-03-29 12Z: 15362 6073 21435 13436 5071 18508 13462 5080 18542 16878 4336 21214 110 71 99 125 85 114 127 86 116 2008-04-03 12Z: 12231 5854 18085 10454 4979 15432 10481 4987 15468 14306 4283 18589 117 73 103 136 86 120 139 87 122 2008-04-08 12Z: 15159 7141 22300 13237 6100 19337 13261 6108 19369 15381 4712 20093 101 66 90 116 77 104 118 78 105 2008-04-13 12Z: 14682 7642 22324 12990 6598 19588 13014 6606 19620 15608 4971 20579 106 65 92 120 75 105 122 76 106 2008-04-18 12Z: 14474 8197 22671 12688 7228 19916 12712 7237 19948 15589 5362 20951 108 65 92 123 74 105 125 75 106 2008-04-23 12Z: 14112 8721 22834 12398 7574 19972 12422 7583 20004 15567 5556 21123 110 64 93 125 73 106 127 74 107 2008-04-28 12Z: 14092 8999 23091 12394 7676 20069 12415 7685 20100 15670 5728 21398 111 64 93 126 75 106 128 75 108 2008-05-03 12Z: 13906 9498 23403 12223 8274 20498 12245 8283 20528 15721 6087 21808 113 64 93 128 73 106 130 74 108 2008-05-08 12Z: 13798 9934 23732 12081 8736 20816 12102 8744 20846 15530 6374 21905 113 64 92 128 73 105 130 73 106 2008-05-13 12Z: 13479 10362 23841 11738 9232 20970 11762 9240 21002 15394 6670 22065 114 64 93 131 72 105 133 73 106 2008-05-18 12Z: 13130 10825 23956 11401 9658 21059 11423 9666 21089 15028 7060 22089 114 65 92 132 73 105 134 73 106 2008-05-22 12Z: 12812 11212 24023 11116 9997 21114 11138 10005 21144 14810 7302 22112 116 65 92 133 73 105 135 73 106 2008-05-28 12Z: 12674 11825 24499 10848 10508 21357 10869 10516 21385 14351 7711 22062 113 65 90 132 73 103 134 74 104 2008-06-02 12Z: 12435 12289 24723 10688 11064 21751 10709 11071 21780 14128 8149 22277 114 66 90 132 74 102 134 74 103 2008-06-07 12Z: 12002 12815 24818 10126 11471 21598 10147 11480 21628 13442 8545 21987 112 67 89 132 74 102 135 75 103 2008-06-13 18Z: 11572 13572 25144 9676 12186 21863 9698 12196 21894 12679 9100 21779 110 67 87 131 75 99 133 75 101 2008-06-17 12Z: 11048 13827 24875 9158 12449 21606 9180 12458 21638 12059 9408 21468 109 68 86 131 76 99 134 76 100 2008-06-22 12Z: 10488 14391 24879 8556 13152 21708 8578 13161 21739 11208 10030 21238 107 70 85 131 76 98 133 77 99 2008-06-27 12Z: 10354 14785 25139 8398 13438 21835 8419 13448 21866 10504 10388 20891 101 70 83 125 77 96 127 78 96 2008-07-02 12Z: 10047 14817 24865 7977 13464 21441 7998 13473 21470 9450 10748 20198 94 73 81 118 80 94 120 80 95 2008-07-07 12Z: 9514 15267 24781 7493 13888 21380 7513 13897 21410 8690 11145 19835 91 73 80 116 80 93 118 81 93 2008-07-12 12Z: 9033 15446 24479 6935 13899 20834 6956 13908 20864 7936 11408 19345 88 74 79 114 82 93 116 82 94 2008-07-17 12Z: 8372 15994 24366 6567 14486 21054 6587 14496 21083 7429 11916 19345 89 75 79 113 82 92 115 83 93 2008-07-22 12Z: 7978 16211 24189 6264 14654 20918 6282 14664 20946 6938 12265 19203 87 76 79 110 84 92 112 84 92 2008-07-27 12Z: 7202 16008 23210 5703 14442 20145 5720 14452 20171 6559 12470 19029 91 78 82 115 86 94 117 87 95 2008-08-01 12Z: 6667 16618 23285 5154 14971 20125 5170 14981 20151 5971 12839 18810 90 77 81 115 86 93 118 86 94 2008-08-06 12Z: 6349 16890 23239 4934 15197 20131 4949 15206 20156 5529 13191 18720 87 78 81 112 87 93 114 87 94 2008-08-11 12Z: 5661 17222 22883 4288 15840 20128 4303 15850 20153 5081 13848 18929 90 80 83 118 87 94 120 88 95 2008-08-16 12Z: 5168 17530 22698 4014 15829 19843 4027 15838 19865 4867 14022 18888 94 80 83 121 89 95 123 89 96 2008-08-21 18Z: 4901 17444 22345 3847 15767 19614 3859 15776 19635 4797 14380 19177 98 82 86 124 91 98 126 92 98 2008-08-26 12Z: 4355 17510 21865 3451 15921 19373 3462 15930 19392 4536 14690 19226 104 84 88 131 92 99 133 93 100 2008-08-31 12Z: 4459 17772 22232 3531 16098 19629 3543 16106 19649 4553 14974 19527 102 84 88 129 93 99 131 93 100 2008-09-05 12Z: 4283 17949 22232 3449 16215 19664 3460 16224 19684 4491 15278 19769 105 85 89 130 94 100 132 95 101 2008-09-10 12Z: 4020 17754 21774 3254 15939 19192 3262 15949 19211 4377 15468 19846 109 87 91 134 97 103 136 97 104 2008-09-15 12Z: 4163 17794 21957 3397 15985 19382 3407 15994 19401 4450 15678 20128 107 88 92 131 98 104 133 98 104 2008-09-20 12Z: 4312 17882 22194 3530 15950 19480 3538 15960 19499 4576 15931 20507 106 89 92 129 100 105 131 100 106 2008-09-25 12Z: 4544 17698 22242 3798 15814 19612 3808 15824 19632 4686 16104 20791 103 91 93 123 102 106 125 102 107 2008-09-30 12Z: 4837 17776 22612 4095 15603 19698 4104 15613 19717 4805 16076 20881 99 90 92 117 103 106 119 103 107 2008-10-05 12Z: 5190 17853 23043 4468 15902 20370 4479 15911 20390 4974 16442 21417 96 92 93 111 103 105 113 104 106 2008-10-10 12Z: 6006 17663 23669 5064 15730 20794 5077 15741 20818 5174 16633 21806 86 94 92 102 106 105 103 106 105 2008-10-15 12Z: 6881 17786 24667 5789 15894 21682 5801 15903 21704 5468 16833 22301 79 95 90 94 106 103 96 106 103 2008-10-20 12Z: 7956 17533 25489 6832 15724 22556 6847 15733 22580 5872 17053 22925 74 97 90 86 108 102 87 109 102 2008-10-25 12Z: 8855 17446 26301 7514 15654 23169 7530 15664 23194 6185 17130 23315 70 98 89 82 109 101 83 110 101 2008-10-30 12Z: 9517 17493 27010 8298 15605 23903 8313 15615 23928 6581 17144 23726 69 98 88 79 110 99 80 110 100 2008-11-04 12Z: 9583 17163 26746 8372 15051 23423 8387 15062 23449 6832 16839 23672 71 98 89 81 112 101 83 112 102 2008-11-09 18Z: 10256 16736 26991 9094 14606 23700 9109 14617 23726 7315 16634 23949 71 99 89 80 114 101 81 114 102 2008-11-14 12Z: 10418 16072 26490 9215 13990 23205 9231 14000 23230 7581 16389 23970 73 102 90 82 117 103 83 118 104 Date NH SH Gl NH SH Gl NH SH Gl NH SH Gl NH SH Gl NH SH Gl NH SH Gl Extent / 10³ km² Area / 10³ km² Area+ / 10³ km² Volume / km³ ThickE / cm ThickA / cm ThickT / cm
