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Validation of LRSID products

View validation statistics and plots for: The latest version of the Validation Report is here.

NH Validation results for merged / multi-sensor product

In the following table, monthly validation statistics for the multi-sensor/merged sea ice drift product are reported upon. X and Y denote the 2 components of the drift vectors. b() is the bias and s() the standard deviation of the error e(X) = Xproduct - Xreference (in km). Columns 6, 7 and 8 are respectively the slope, the intercept of the regression line, and the Pearson correlation coefficient between Product and Reference data pairs. N is the number of collocation data pairs.
Merged / Multi-sensor product (NH)
Periodb(X) [km]b(Y) [km]s(X) [km]s(Y) [km]ab [km]corrNplots
Jan2012-0.291-0.0603.0012.4750.95-0.2980.98266map1, map2
Feb2012-0.195+0.0432.2752.1730.95-0.0840.97241
Mar2012-0.150-0.1772.5572.2360.95-0.1560.94265
Apr2012-0.378+0.5343.0963.0850.87+0.1810.94234
May2012--------------0
Jun2012--------------0
Jul2012--------------0map1, map2
Aug2012--------------0
Sep2012--------------0
Oct2012-0.355+0.0914.1323.9910.92+0.0890.95436
Nov2012-0.017+0.0733.8023.7950.95+0.0970.97506
Dec2012+0.096+0.0443.3492.9880.93+0.1920.96526
Jan2013+0.448+0.0963.1733.0760.96+0.0380.98430map1, map2
Feb2013+0.187-0.2902.8903.1120.92-0.0510.93354
Mar2013-0.089+0.5423.7613.6820.92+0.2260.97351
Apr2013-0.163-0.6843.0415.5460.82-0.2630.92358
May2013--------------0
Jun2013--------------0
Jul2013--------------0map1, map2
Aug2013--------------0
Sep2013--------------0
Oct2013-0.548-0.5963.7693.9680.95-0.2950.96450
Nov2013-0.113-0.6253.9434.9740.90+0.2370.95424
Dec2013+0.265-0.2053.1703.0710.95+0.0250.97335
Jan2014+0.404+0.3063.8343.5680.93+0.1510.96328map1, map2, map3, qqplot, scattdXdY, scatteXeY
Feb2014+0.005-0.3253.1383.3220.94-0.1760.96317
Mar2014-0.120-0.0692.7912.7050.98-0.0570.96427
Apr2014-0.339-0.1473.3513.1180.97-0.0990.96514
May2014--------------0
Jun2014--------------0
Jul2014--------------0map1, map2, map3, qqplot, scattdXdY, scatteXeY
Aug2014--------------0
Sep2014--------------0
Oct2014-0.225+0.2804.7705.1080.90-0.1480.93413
Nov2014+0.459-0.1013.5083.4630.95+0.2660.96458
Dec2014-0.187-0.2662.8832.9610.97-0.2430.97477
Jan2015+0.138-0.3013.2023.0350.93-0.0800.95489map1, map2, map3, qqplot, scattdXdY, scatteXeY
Feb2015-0.669-0.4063.6012.8310.92-0.3360.96403
Mar2015-0.288-0.3873.7304.3340.82-0.0190.93405
Apr2015+0.172-0.4043.4112.8030.95-0.1010.96366
May2015--------------0
Jun2015--------------0
Jul2015--------------0map1, map2, map3, qqplot, scattdXdY, scatteXeY
Aug2015--------------0
Sep2015--------------0
Oct2015-0.497+0.7544.4644.8940.77+1.4020.91143
Nov2015-0.455-0.1233.1653.0040.89-0.0670.97417
Dec2015-0.218-0.3763.1353.4980.93-0.1690.97415
Jan2016-0.049-0.1452.3622.4280.95-0.0410.98613mapMisLen, mapTime, mapNetw, qqplot, scattdXdY, scatteXeY
Feb2016-0.262+0.2602.6692.3460.960.0390.98536
Mar2016-0.463-0.1432.7802.2310.91-0.1140.95508
Apr2016+0.096-0.5361.6282.1470.96-0.1100.97446
May2016--------------0
Jun2016--------------0
Jul2016--------------0mapMisLen, mapTime, mapNetw, qqplot, scattdXdY, scatteXeY
Aug2016--------------0
Sep2016--------------0
Oct2016+0.391-0.3255.0984.6120.880.2070.94379
Nov2016-0.409-0.5123.8444.4090.90-0.4100.96385
Dec2016+0.100-0.9473.1714.8190.88-0.1790.96335
Jan2017-0.379+0.1362.3912.0710.970.1410.98258mapMisLen, mapTime, mapNetw, qqplot, scattdXdY, scatteXeY
Feb2017+0.237+0.2441.7511.7080.980.2850.99219
Mar2017-0.321-0.0492.3402.0990.940.4150.98251
Apr2017+0.201-0.1471.7101.8250.980.0830.98231
May2017+1.057-1.3753.7182.4420.96-0.3410.9426
Jun2017-0.578-1.2654.0894.2310.90-0.7100.93140
Validation results for the multi-sensor ice drift (multi-oi) product in North Hemisphere. See text for details.

Validation dataset

Drifting stations

Validation is performed by collocation of the drift vectors with the trajectories of in situ drifters. Those drifting objects are generally buoys (e.g. the Ice Tethered Profilers) or ice camps (e.g. the Russian manned stations) that report their position at typically hourly intervals. Those trajectories are generally made available in near-real-time or at the end of the mission onto the ice.
Position records are acquired either via the GPS (e.g. those of the ITPs) or the Argos Doppler-shift system (those of the iABP). GPS positions are very accurate (accuracy better than 50 m) while those obtained by Argos have worse accuracy (approximately 350 m for 'high quality' records).

SAR-based motion vectors

The ice drift product processed from Envisat ASAR WSM scenes at the Danish Technological Institute (DTU) and available via the MyOcean project have been used as validation data for the OSI SAF low resolution ice drit products (mainly for SH).
Vectors originally spanning 24-hours are concatenated to producte 2-days displacements that are collocated with the OSI-405 ice drift vectors.

Collocation strategy

A nearest-neighbor approach is used for the collocation, and a collocation pair enters the validation dataset if and only if:
  • The distance between the satellite product and the buoy is less than 30 km; and
  • the mismatch of start time of the drift is less than 3 hours; and
  • the mismatch of drift duration is less than 3 hours.
In the case when several validation vectors are collocated to a unique OSI-405 ice drift vector, only one is kept for the validation, preferably GPS-based vectors, then SAR-based, then Argos-based. The matchup database is futher thinned so that all data pairs are at least 2 * 62.5 = 125 km apart.

Acknowledgement and data sources

  • The Ice-Tethered Profiler data are collected and made available by the Ice-Tethered Profiler Program based at the Woods Hole Oceanographic Institution.
  • Ice Mass Balance buoys from the Cold Regions Research and Engineering Laboratory (CRREL) are collected and made available by Perovich, et al. (2013).
  • Ice Mass Balance buoys in NAACOS (Danish strategic research council), KOPRI (co-funded between EU-Access and KOPRI), EU FP7 ACCESS, and AWI campaigns are operated by the Scottish Association for Marine Science.
  • GPS-located data from Russsian stations (NP35, NP36, NP37, NP38, etc...) are kindly provided by the Arctic and Antarctic Research Institute (AARI) of Roshydromet, PIs Vladimir Sokolov and Vasily Smolyanitsky.
  • Position records from the International Arctic Buoy Programme IABP (Argos positioning) are kindly provided by the University of Washington, PIs Ignatius Rigor and Mark Ortmeyer.
  • ASAR WSM ice motion vectors are processed at the Danish Technical University - Space institute (see http://www.seaice.dk) and distributed by the Sea Ice and Winds Thematic Assembly Centre (SIW TAC) of the MyOcean project.



Validation results for the single-sensor products

AMSR2 GCOM-W1 (operational since October 2015)

Single-sensor product: AMSR2 (GCOM-W1)
Periodb(X) [km]b(Y) [km]s(X) [km]s(Y) [km]ab [km]corrNplots
Jul2015--------------0map1, map2, map3, qqplot, scattdXdY, scatteXeY
Aug2015--------------0
Sep2015--------------0
Oct2015-0.825+0.5895.7475.0040.75+1.3510.89133
Nov2015-0.309-0.1932.7842.4610.93-0.0990.98390
Dec2015-0.124+0.0532.5442.2960.98-0.0070.98374
Jan2016+0.058-0.0501.6351.6600.990.0120.99568mapMisLen, mapTime, mapNetw, qqplot, scattdXdY, scatteXeY
Feb2016-0.217+0.2192.0322.2270.980.0190.98478
Mar2016-0.165-0.0711.4831.7290.98-0.0900.98416
Apr2016+0.066-0.5781.5252.0580.97-0.1760.97374
May2016--------------0
Jun2016--------------0
Jul2016--------------0mapMisLen, mapTime, mapNetw, qqplot, scattdXdY, scatteXeY
Aug2016--------------0
Sep2016--------------0
Oct2016+0.065-0.2943.9823.9630.930.0270.95318
Nov2016-0.164-0.5983.0533.4130.94-0.3990.97358
Dec2016-0.177-1.3083.1945.0030.88-0.5590.95297
Jan2017-0.451+0.2632.1011.6860.990.0040.99234mapMisLen, mapTime, mapNetw, qqplot, scattdXdY, scatteXeY
Feb2017+0.350+0.2171.5691.5260.980.3300.99220
Mar2017-0.155+0.0231.6441.7780.960.3390.99245
Apr2017+0.117-0.1691.6901.7740.980.0260.98221
May2017--------------0
Jun2017--------------0
Validation results for the amsr2-gw1 (single-sensor) ice drift product. Same columns as tables above.

SSMIS F17 (earlier SSM/I F15)


Single-sensor product: SSM/I (F15)
Periodb(X) [km]b(Y) [km]s(X) [km]s(Y) [km]ab [km]corrNplots
Jan2012-0.477+0.0043.7443.0430.97-0.3060.96255map1, map2
Feb2012-0.151+0.0402.7022.8280.97-0.0590.95242
Mar2012-0.243-0.1262.9102.7760.98-0.1810.92264
Apr2012-0.480+0.4463.7893.7420.85-0.0340.90196
May2012--------------0
Jun2012--------------0
Jul2012--------------0map1, map2
Aug2012--------------0
Sep2012--------------0
Oct2012-0.432+0.5934.4054.8230.94+0.2550.93383
Nov2012-0.067-0.1864.8144.8440.96-0.0650.95473
Dec2012+0.117+0.2543.5223.5570.94+0.2590.95508
Switch to SSMIS (F17)
Jan2013+0.484-0.1193.1593.3570.97-0.0070.97408map1, map2
Feb2013+0.089-0.1513.0882.5700.98-0.0340.94346
Mar2013+0.021+0.6343.6693.4230.94+0.3300.97316
Apr2013-0.156-0.4433.8365.6200.84-0.3540.90312
May2013--------------0
Jun2013--------------0
Jul2013--------------0map1, map2
Aug2013--------------0
Sep2013--------------0
Oct2013-0.411-0.5224.4374.2030.97-0.2810.95406
Nov2013-0.133-0.1074.1613.6900.95+0.1320.96389
Dec2013+0.200-0.0772.9763.3980.96+0.0540.96327
Jan2014+0.298+0.1804.2733.8940.94+0.0460.95325map1, map2, map3, qqplot, scattdXdY, scatteXeY
Feb2014+0.022-0.2784.3074.0040.95-0.1210.94306
Mar2014-0.137-0.1193.3122.9110.99-0.1150.95414
Apr2014-0.320-0.0354.0543.8680.98-0.1060.94460
May2014--------------0
Jun2014--------------0
Jul2014--------------0map1, map2, map3, qqplot, scattdXdY, scatteXeY
Aug2014--------------0
Sep2014--------------0
Oct2014-0.365+0.3154.7955.0900.93-0.1550.93346
Nov2014+0.506-0.1203.6833.1660.97+0.2450.96419
Dec2014-0.135-0.1483.4273.1890.98-0.1490.96464
Jan2015+0.032-0.2173.6493.3900.95-0.0920.94474map1, map2, map3, qqplot, scattdXdY, scatteXeY
Feb2015-0.360-0.4343.3902.9010.96-0.3150.96380
Mar2015+0.001-0.2063.2723.0720.92-0.0130.95378
Apr2015-0.008-0.3633.8263.6250.95-0.1960.94337
May2015--------------0
Jun2015--------------0
Jul2015--------------0map1, map2, map3, qqplot, scattdXdY, scatteXeY
Aug2015--------------0
Sep2015--------------0
Oct2015-0.422+0.6404.5096.3080.81+1.1990.88127
Nov2015+0.054-0.0324.2353.8810.91+0.1920.95360
Dec2015-0.406-0.5234.1453.8120.96-0.3780.96376
Jan2016+0.001-0.1423.8154.0930.98-0.0520.94525mapMisLen, mapTime, mapNetw, qqplot, scattdXdY, scatteXeY
Feb2016-0.291+0.4134.4493.8330.960.1110.94438
Mar2016-0.172-0.6693.4073.8320.97-0.3760.90367
Apr2016+0.238-0.4583.0133.1330.99-0.0870.93370
May2016--------------0
Jun2016--------------0
Jul2016--------------0mapMisLen, mapTime, mapNetw, qqplot, scattdXdY, scatteXeY
Aug2016--------------0
Sep2016--------------0
Oct2016+0.550-0.5824.9204.7770.890.1390.94310
Nov2016+0.233-0.1804.9194.5160.93-0.0180.94340
Dec2016+0.275-0.4684.6984.8260.910.0630.93295
Jan2017-0.541-0.0803.4183.6240.96-0.0260.96218mapMisLen, mapTime, mapNetw, qqplot, scattdXdY, scatteXeY
Feb2017+0.331+0.2153.4972.9980.970.3440.96215
Mar2017-0.367-0.2293.6943.5320.930.3430.95243
Apr2017+0.527-0.2973.2853.3681.020.0520.93215
May2017--------------0
Jun2017--------------0
Validation results for the ssmis-f17 and ssmi-f15 (single-sensor) ice drift product. Same columns as tables above.

ASCAT MetopA

Single-sensor product: ASCAT (MetOp-A)
Periodb(X) [km]b(Y) [km]s(X) [km]s(Y) [km]ab [km]corrNplots
Jan2012-0.195+0.0113.3362.9530.97-0.1640.97265map1, map2
Feb2012-0.270+0.0552.7892.9120.95-0.1170.95241
Mar2012-0.054-0.2893.5313.0020.97-0.1660.88263
Apr2012-0.540+0.6774.1204.1030.86+0.1610.89222
May2012--------------0
Jun2012--------------0
Jul2012--------------0map1, map2
Aug2012--------------0
Sep2012--------------0
Oct2012-0.371-0.3455.0715.2590.95-0.1900.91384
Nov2012-0.059+0.0934.4564.5680.95+0.0900.96498
Dec2012+0.300-0.0854.0163.6660.96+0.1620.94513
Jan2013+0.278+0.1174.4083.9820.96-0.0130.96418map1, map2
Feb2013+0.538+0.0164.1924.2240.93+0.2990.84335
Mar2013-0.230+0.3674.7764.6440.95+0.0940.95319
Apr2013+0.049+0.0253.6834.5840.93+0.0200.92323
May2013--------------0
Jun2013--------------0
Jul2013--------------0map1, map2
Aug2013--------------0
Sep2013--------------0
Oct2013-0.353-0.6665.1305.6330.95-0.2220.92421
Nov2013-0.183-0.4474.7004.7750.94-0.0100.95384
Dec2013+0.246-0.2243.7763.9210.96-0.0030.95323
Jan2014+0.589+0.6724.5664.6030.94+0.4400.94317map1, map2, map3, qqplot, scattdXdY, scatteXeY
Feb2014+0.077-0.3603.4494.1030.95-0.1510.95317
Mar2014-0.142+0.1073.3873.9340.98+0.0190.93417
Apr2014-0.173-0.2353.4853.8620.98-0.1060.95482
May2014--------------0
Jun2014--------------0
Jul2014--------------0map1, map2, map3, qqplot, scattdXdY, scatteXeY
Aug2014--------------0
Sep2014--------------0
Oct2014+0.211-0.0466.5056.8600.94+0.0500.87326
Nov2014+0.366+0.0885.0845.4830.95+0.3240.92420
Dec2014-0.210-0.4063.8414.3170.98-0.3140.94457
Jan2015+0.248-0.4103.8204.0390.94-0.0790.92479map1, map2, map3, qqplot, scattdXdY, scatteXeY
Feb2015-0.752-0.5724.8004.5080.91-0.4560.92382
Mar2015-0.060-0.2163.6693.9920.93-0.0790.92369
Apr2015+0.048-0.2333.7923.6540.99-0.0950.94331
May2015--------------0
Jun2015--------------0
Jul2015--------------0map1, map2, map3, qqplot, scattdXdY, scatteXeY
Aug2015--------------0
Sep2015--------------0
Oct2015+0.425+0.4974.2294.5630.94+0.7850.91123
Nov2015-0.280-0.0974.6994.6660.93-0.0550.91366
Dec2015+0.081-0.2864.9254.1490.96-0.0490.94378
Jan2016+0.015-0.0183.8443.2820.970.0250.95568mapMisLen, mapTime, mapNetw, qqplot, scattdXdY, scatteXeY
Feb2016-0.330+0.4034.2043.8270.970.0700.95473
Mar2016-0.189-0.2474.2154.0480.97-0.1700.87385
Apr2016+0.079-0.1783.6323.9940.980.0050.90358
May2016--------------0
Jun2016--------------0
Jul2016--------------0mapMisLen, mapTime, mapNetw, qqplot, scattdXdY, scatteXeY
Aug2016--------------0
Sep2016--------------0
Oct2016+0.322-0.7015.8415.6620.860.0500.90310
Nov2016-0.254-0.1444.9835.6430.92-0.2390.93354
Dec2016-0.055-0.5755.2266.1400.91-0.1920.91306
Jan2017-0.567+0.1304.5244.3170.960.1090.93236mapMisLen, mapTime, mapNetw, qqplot, scattdXdY, scatteXeY
Feb2017-0.151+0.2624.6454.3670.990.0880.93217
Mar2017-0.303-0.2004.2134.0150.940.2550.94243
Apr2017+0.598+0.3773.8403.4330.970.5700.92218
May2017--------------0
Jun2017--------------0
Validation results for the ascat-metopA (single-sensor) ice drift product. Same columns as tables above.

SH Validation results for merged / multi-sensor product

Merged / Multi-sensor product (SH)
Periodb(X) [km]b(Y) [km]s(X) [km]s(Y) [km]ab [km]corrNplots
Jul2016-0.103-0.5576.3816.9480.86-1.0820.95322mapMisLen, mapTime, mapNetw, qqplot, scattdXdY, scatteXeY
Aug2016+0.094+0.6434.3795.6970.91-0.3480.96378
Sep2016-1.100+0.6845.9446.8160.93-0.4040.97321
Oct2016-1.256+0.7767.1175.7230.89-0.6660.96292
Nov2016--------------0
Dec2016--------------0
Jan2017--------------0mapMisLen, mapTime, mapNetw, qqplot, scattdXdY, scatteXeY
Feb2017--------------0
Mar2017--------------0
Apr2017-0.602+1.6175.4606.4770.80-1.6980.8820
May2017--------------0
Jun2017--------------0
Validation results for the multi-sensor ice drift (multi-oi) product in South Hemisphere. See text for details.

SH AMSR2 GCOM-W1 (operational since October 2015)

Single-sensor product: AMSR2 (GCOM-W1)
Periodb(X) [km]b(Y) [km]s(X) [km]s(Y) [km]ab [km]corrNplots
Jul2016-0.256-0.2025.9536.5590.87-0.9910.95293mapMisLen, mapTime, mapNetw, qqplot, scattdXdY, scatteXeY
Aug2016+0.627+0.6694.5565.9560.91-0.1090.96335
Sep2016-0.319-0.1144.7185.6130.98-0.2790.98279
Oct2016-0.064+0.6825.2975.5770.940.0110.97248
Nov2016--------------0
Dec2016--------------0
Jan2017--------------0mapMisLen, mapTime, mapNetw, qqplot, scattdXdY, scatteXeY
Feb2017--------------0
Mar2017--------------0
Apr2017+1.526-1.3513.0723.3070.95-0.3660.9614
May2017--------------0
Jun2017--------------0
Validation results for the amsr2-gw1 (single-sensor) ice drift product. Same columns as tables above.

SSMIS F17 (earlier SSM/I F15)


Single-sensor product: SSM/I (F15)
Periodb(X) [km]b(Y) [km]s(X) [km]s(Y) [km]ab [km]corrNplots
Jul2016-0.022-0.7396.3866.7800.92-0.9180.94271mapMisLen, mapTime, mapNetw, qqplot, scattdXdY, scatteXeY
Aug2016+0.046+0.7496.0566.9820.92-0.2270.94325
Sep2016-1.182+0.2478.4617.8530.94-0.7040.94209
Oct2016-0.137+0.0587.1817.4170.95-0.3610.94204
Nov2016--------------0
Dec2016--------------0
Jan2017--------------0mapMisLen, mapTime, mapNetw, qqplot, scattdXdY, scatteXeY
Feb2017--------------0
Mar2017--------------0
Apr2017+2.358-6.3033.3944.6580.35-6.1230.357
May2017--------------0
Jun2017--------------0
Validation results for the ssmis-f17 and ssmi-f15 (single-sensor) ice drift product. Same columns as tables above.

ASCAT MetopA

Single-sensor product: ASCAT (MetOp-A)
Periodb(X) [km]b(Y) [km]s(X) [km]s(Y) [km]ab [km]corrNplots
Jul2016-0.252-0.3104.3014.6790.96-0.4750.97232mapMisLen, mapTime, mapNetw, qqplot, scattdXdY, scatteXeY
Aug2016+0.812+0.9435.0996.3720.920.2930.95290
Sep2016-1.227+0.2195.7806.1810.94-0.7790.96157
Oct2016-1.241+0.8798.2027.2480.80-1.2610.88109
Nov2016--------------0
Dec2016--------------0
Jan2017--------------0mapMisLen, mapTime, mapNetw, qqplot, scattdXdY, scatteXeY
Feb2017--------------0
Mar2017--------------0
Apr2017-2.144+4.9494.44511.6600.79-2.3110.866
May2017--------------0
Jun2017--------------0
Validation results for the ascat-metopA (single-sensor) ice drift product. Same columns as tables above.

AMSR2 GCOM-W1 (operational since October 2015)

SSMIS F17

ASCAT MetopA

   
       
     

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