Copernicus Marine Service Arctic MFC: Validation of thin sea ice

Validation based on satellite data from SMOS

Validation of the Copernicus Marine ARC MFC results for the thickness of thin sea ice is performed using a dataset which is derived from observations from the Soil Moisture and Ocean Salinity (SMOS) satellite. The sea ice thickness data are produced using an emperical algorithm developed by Tian-Kunze et al.. The algorithm takes advantage of data from the microwave radiometer onboard the SMOS satellite. The operational product has been documented by Kaleschke et al..

SMOS-based results for the thickness of thin ice are available (before Oct. 2019) from the Uni Hamburg OPeNDAP server at http://icdc.cen.uni-hamburg.de/thredds/aggregationSmosIcethicknessCatalog.html. From October 2019 SMOS data are available from Alfred Wegener Institute on ftp.awi.de/sea_ice/product/smos/v3.3/nh. SMOS processing was funded by the Support to Science Element Program from ESA.

Results by bulletin date
January 2024
01-04
01-11
01-18
01-25

February 2024
02-01
02-08
02-15
02-22
02-29

March 2024
03-07
03-14
03-21
03-28

January 2023
01-05
01-12
01-19
01-26

February 2023
02-02
02-09
02-16
02-23

March 2023
03-02
03-09
03-16
03-23
03-30

April 2023
04-06
04-13
04-20
04-27

May 2023
05-04
05-11
05-18
05-25

June 2023
06-01
06-08
06-15
06-22
06-29

July 2023
07-06
07-13
07-20
07-27

August 2023
08-03
08-10
08-17
08-24
08-31

September 2023
09-07
09-14
09-21
09-28

October 2023
10-05
10-12
10-19
10-26

November 2023
11-02
11-09
11-16
11-23
11-30

December 2023
12-07
12-14
12-21
12-28

January 2022
01-06
01-13
01-20
01-27

February 2022
02-03
02-10
02-17
02-24

March 2022
03-03
03-10
03-17
03-24
03-31

April 2022
04-07
04-14
04-21
04-28

May 2022
05-05
05-12
05-19
05-26

June 2022
06-02
06-09
06-16
06-23
06-30

July 2022
07-07
07-14
07-21
07-28

August 2022
08-04
08-11
08-18
08-25

September 2022
09-01
09-08
09-15
09-22
09-29

October 2022
10-06
10-13
10-20
10-27

November 2022
11-03
11-10
11-17
11-24

December 2022
12-01
12-08
12-15
12-22
12-29

January 2021
01-07
01-14
01-21
01-28

February 2021
02-04
02-11
02-18
02-25

March 2021
03-04
03-11
03-18
03-25

April 2021
04-01
04-08
04-15
04-22
04-29

May 2021
05-06
05-13
05-20
05-27

June 2021
06-03
06-10
06-17
06-24

July 2021
07-01
07-08
07-15
07-22
07-29

August 2021
08-05
08-12
08-19
08-26

September 2021
09-02
09-09
09-16
09-23
09-30

October 2021
10-07
10-14
10-21
10-28

November 2021
11-04
11-11
11-18
11-25

December 2021
12-02
12-09
12-16
12-23
12-30

January 2020
01-02
01-09
01-16
01-23
01-30

February 2020
02-06
02-13
02-20
02-27

March 2020
03-05
03-12
03-19
03-26

April 2020
04-02
04-09
04-16
04-23
04-30

May 2020
05-07
05-14
05-21
05-28

June 2020
06-04
06-11
06-18
06-25

July 2020
07-02
07-09
07-16
07-23
07-30

August 2020
08-06
08-13
08-20
08-27

September 2020
09-03
09-10
09-17
09-24

October 2020
10-01
10-08
10-15
10-22
10-29

November 2020
11-05
11-12
11-19
11-26

December 2020
12-03
12-10
12-17
12-24
12-31

January 2019
01-03
01-10
01-17
01-24
01-31

February 2019
02-07
02-14
02-21
02-28

March 2019
03-07
03-14
03-21
03-28

April 2019
04-04
04-11
04-18
04-25

May 2019
05-02
05-09
05-16
05-23
05-30

June 2019
06-06
06-13
06-20
06-27

July 2019
07-04
07-11
07-18
07-25

August 2019
08-01
08-08
08-15
08-22
08-29

September 2019
09-05
09-12
09-19
09-26

October 2019
10-03
10-10
10-17
10-24
10-31

November 2019
11-07
11-14
11-21
11-28

December 2019
12-05
12-12
12-19
12-26

January 2018
01-04
01-11
01-18
01-25

February 2018
02-01
02-08
02-15
02-22

March 2018
03-01
03-08
03-15
03-22
03-29

April 2018
04-05
04-12
04-19
04-26

May 2018
05-03
05-10
05-17
05-24
05-31

June 2018
06-07
06-14
06-21
06-28

July 2018
07-05
07-12
07-19
07-26

August 2018
08-02
08-09
08-16
08-23
08-30

September 2018
09-06
09-13
09-20
09-27

October 2018
10-04
10-11
10-18
10-25

November 2018
11-01
11-08
11-15
11-22
11-29

December 2018
12-06
12-13
12-20
12-27

January 2017
01-05
01-12
01-19
01-26

February 2017
02-02
02-09
02-16
02-23

March 2017
03-02
03-09
03-16
03-23
03-30

April 2017
04-06
04-13
04-20
04-27

May 2017
05-04
05-11
05-18
05-25

June 2017
06-01
06-08
06-15
06-22
06-29

July 2017
07-06
07-13
07-20
07-27

August 2017
08-03
08-10
08-17
08-24
08-31

September 2017
09-07
09-14
09-21
09-28

October 2017
10-05
10-12
10-19
10-26

November 2017
11-02
11-09
11-16
11-23
11-30

December 2017
12-07
12-14
12-21
12-28

January 2016
01-07
01-14
01-21
01-28

February 2016
02-04
02-11
02-18
02-25

March 2016
03-03
03-10
03-17
03-24
03-31

April 2016
04-07
04-14
04-21
04-28

May 2016
05-05
05-12
05-19
05-26

June 2016
06-02
06-09
06-16
06-23
06-30

July 2016
07-07
07-14
07-21
07-28

August 2016
08-04
08-11
08-18
08-25

September 2016
09-01
09-08
09-15
09-22
09-29

October 2016
10-06
10-13
10-20
10-27

November 2016
11-03
11-10
11-17
11-24

December 2016
12-01
12-08
12-15
12-22
12-29

April 2015
04-02
04-09
04-16
04-23
04-30

May 2015
05-07
05-14
05-21
05-28

June 2015
06-04
06-11
06-18
06-25

July 2015
07-02
07-09
07-16
07-23
07-30

August 2015
08-06
08-13
08-20
08-27

September 2015
09-03
09-10
09-17
09-24

October 2015
10-01
10-08
10-15
10-22
10-29

November 2015
11-05
11-12
11-19
11-26

December 2015
12-03
12-10
12-17
12-24
12-31


Processing

We use results for the sea ice thickness and the uncertainty of these data, derived from the SMOS observations. Samples of these two fields are displayed below.

SMOS sea ice thickness SMOS sea ice thickness
SMOS sea ice thickness on 2017-03-09 Thickness uncertainty on 2017-03-09

Before the comparison of model results and SMOS-based observations is performed, we restrict the validation region by requiring that the uncertainty does not exceed either 1 m or 75% of the seaice thickness (see the description of Data quality on the Sea Ice Thickness from L3C SMOS web page).

Next, the sea ice thickness bias and RMS difference between model results and observations are computed. Finally, the thickness distribution is categorized into pre-defined thickness classes, and the model/observation category match-up is displayed in contingency tables.

Validation based on satellite data from CryoSat-2

Validation of the Copernicus Marine ARC MFC results for the thickness of thick sea ice is performed using a dataset which is derived from observations from the CryoSat-2 satellite, using observations from its SAR Interferometric Radar Altimeter (SIRAL) instrument. The sea ice thickness data set we use based on the SIRAL observations is provided by the Centre for Polar Observation and Modelling (CPOM), which also provides details and references on data processing that is applied.

CPOM provides access to the sea ice thickness results in an interactive interface. Data are available from CPOM under http://www.cpom.ucl.ac.uk/csopr/sidata/.

Results by bulletin date
January 2024
01-04
01-11
01-18
01-25

February 2024
02-01
02-08
02-15
02-22
02-29

March 2024
03-07
03-14
03-21
03-28

January 2023
01-05
01-12
01-19
01-26

February 2023
02-02
02-09
02-16
02-23

March 2023
03-02
03-09
03-16
03-23
03-30

April 2023
04-06
04-13
04-20
04-27

May 2023
05-04
05-11
05-18
05-25

June 2023
06-01
06-08
06-15
06-22
06-29

July 2023
07-06
07-13
07-20
07-27

August 2023
08-03
08-10
08-17
08-24
08-31

September 2023
09-07
09-14
09-21
09-28

October 2023
10-05
10-12
10-19
10-26

November 2023
11-02
11-09
11-16
11-23
11-30

December 2023
12-07
12-14
12-21
12-28

January 2022
01-06
01-13
01-20
01-27

February 2022
02-03
02-10
02-17
02-24

March 2022
03-03
03-10
03-17
03-24
03-31

April 2022
04-07
04-14
04-21
04-28

May 2022
05-05
05-12
05-19
05-26

June 2022
06-02
06-09
06-16
06-23
06-30

July 2022
07-07
07-14
07-21
07-28

August 2022
08-04
08-11
08-18
08-25

September 2022
09-01
09-08
09-15
09-22
09-29

October 2022
10-06
10-13
10-20
10-27

November 2022
11-03
11-10
11-17
11-24

December 2022
12-01
12-08
12-15
12-22
12-29

January 2021
01-07
01-14
01-21
01-28

February 2021
02-04
02-11
02-18
02-25

March 2021
03-04
03-11
03-18
03-25

April 2021
04-01
04-08
04-15
04-22
04-29

May 2021
05-06
05-13
05-20
05-27

June 2021
06-03
06-10
06-17
06-24

July 2021
07-01
07-08
07-15
07-22
07-29

August 2021
08-05
08-12
08-19
08-26

September 2021
09-02
09-09
09-16
09-23
09-30

October 2021
10-07
10-14
10-21
10-28

November 2021
11-04
11-11
11-18
11-25

December 2021
12-02
12-09
12-16
12-23
12-30

January 2020
01-02
01-09
01-16
01-23
01-30

February 2020
02-06
02-13
02-20
02-27

March 2020
03-05
03-12
03-19
03-26

April 2020
04-02
04-09
04-16
04-23
04-30

May 2020
05-07
05-14
05-21
05-28

June 2020
06-04
06-11
06-18
06-25

July 2020
07-02
07-09
07-16
07-23
07-30

August 2020
08-06
08-13
08-20
08-27

September 2020
09-03
09-10
09-17
09-24

October 2020
10-01
10-08
10-15
10-22
10-29

November 2020
11-05
11-12
11-19
11-26

December 2020
12-03
12-10
12-17
12-24
12-31

January 2019
01-03
01-10
01-17
01-24
01-31

February 2019
02-07
02-14
02-21
02-28

March 2019
03-07
03-14
03-21
03-28

April 2019
04-04
04-11
04-18
04-25

May 2019
05-02
05-09
05-16
05-23
05-30

June 2019
06-06
06-13
06-20
06-27

July 2019
07-04
07-11
07-18
07-25

August 2019
08-01
08-08
08-15
08-22
08-29

September 2019
09-05
09-12
09-19
09-26

October 2019
10-03
10-10
10-17
10-24
10-31

November 2019
11-07
11-14
11-21
11-28

December 2019
12-05
12-12
12-19
12-26

January 2018
01-04
01-11
01-18
01-25

February 2018
02-01
02-08
02-15
02-22

March 2018
03-01
03-08
03-15
03-22
03-29

April 2018
04-05
04-12
04-19
04-26

May 2018
05-03
05-10
05-17
05-24
05-31

June 2018
06-07
06-14
06-21
06-28

July 2018
07-05
07-12
07-19
07-26

August 2018
08-02
08-09
08-16
08-23
08-30

September 2018
09-06
09-13
09-20
09-27

October 2018
10-04
10-11
10-18
10-25

November 2018
11-01
11-08
11-15
11-22
11-29

December 2018
12-06
12-13
12-20
12-27

January 2017
01-12
01-19
01-26

February 2017
02-02
02-09
02-16
02-23

March 2017
03-02
03-09
03-16
03-23
03-30

April 2017
04-06
04-13
04-20
04-27

May 2017
05-04
05-11
05-18
05-25

June 2017
06-01
06-08
06-15
06-22
06-29

July 2017
07-06
07-13
07-20
07-27

August 2017
08-03
08-10
08-17
08-24
08-31

September 2017
09-07
09-14
09-21
09-28

October 2017
10-05
10-12
10-19
10-26

November 2017
11-02
11-09
11-16
11-23
11-30

December 2017
12-07
12-14
12-21
12-28


Processing

We use results for the sea ice thickness, and the uncertainty of these data, derived from the CryoSat observations. The CryoSat data set consists of thickness data along the satellite tracks, aggregated over a 2-week period. Also provided are quality information represented by the standard deviation of these measurements. After discarding thickness values with standard deviations exceeding 75%, the thickness data are projected onto the ARC-MFC PHYS grid prior to the model-data comparison.

Next, sea ice thickness results from ARC-MFC PHYS simulations are averaged over the same 2-week period, and the region without data coveraged is masked. Based on the resulting set of observations and model results, basic statistical quantities are calculated, and maps of shaded contours for the products are plotted. Finally, the thickness distribution is categorized into pre-defined thickness classes, and the model/observation category match-up is displayed in contingency tables. Note that the tabulated dates above for the validation of the thick sea ice corresponds to the last day in the 2-week period under examination.

Region

Validation region

The present version of the coupled sea ice and ocean circulation model used in Copernicus Marine Arctic MFC covers the Arctic Ocean, the North Atlantic Ocean and adjacent ocean regions. The northern part is depicted in the figure to the left. Validation of sea ice thickness from model results is performed for the domain indicated by the blue region in the figure.

Note that the actual region for which the validation is performed varies from day to day due to limitations in the geographical coverage, and also due the screening of data resulting from regionally high estimated uncertainty in the observational product.

Finally, the temporal observational coverage is restricted seasonally. SMOS data are provided for the freeze-up season since the SMOS data poorly reproduce the sea ice thickness in the melting season. CryoSat data are discontinued during the season when meltponds affect the data. Thus, essentially, both products are available during winter, and not available during summer.

Time series

Stat.s time series

Since the CryoSat sea ice thickness data are not available as daily averages, the software for producing time series results cannot easily be adopted to this product. To the left is a time series tailor made for the comparison of sea ice thickness model results with CryoSat data. Shown here are results for the day 1 (black) and day 10 (red) forecasts, for bias (model-observations, full lines) and RMS differences (dashed lines). The two forecast ranges give nearly identical results, so the lines overlap. This time series plot will be updated intermittently only.

ARC-MFC PHYS (TOPAZ)

The model results are produced with the TOPAZ ocean data assimilation model system. Presently, TOPAZ is run weekly with data assimillation one week prior to the bulletin date, followed by a one-week 100 member ensemble simulation ending on the bulletin date, and finally a 10 day deterministic forecast. TOPAZ was developed and is maintained by the Nansen Center.

ARC-MFC PHYS (TOPAZ) results are available as Copernicus Marine product ARCTIC_ANALYSIS_FORECAST_PHYS_002_001_a. An archive of historical forecasts are available from a thredds server.

 
See Met Privacy