Abstract: ESA-CCI sea-ice-ecv phase2 project Envisat and CryoSat-2 monthly mean gridded Arctic sea-ice thickness and uncertainty estimates are combined with daily gridded Arctic satellite passive microwave sea-ice concentration observations and their uncertainties using the SICCI-2 algorithm derived within the same project to obtain an estimate of the Arctic Ocean monthly mean sea-ice volume during winter (October through April). The observational data gap centred at the pole is filled via interpolation as described in the retrieval report: https://icdc.cen.uni-hamburg.de/fileadmin/user_upload/ESA_Sea-Ice-ECV_Phase2/SICCI_Phase2_SIV-Retrieval_Report_v02.pdf. This report does also describe how uncertainties are estimated, and how the Envisat data are bias-corrected with respect to the CryoSat-2 data. The NSIDC sector Arctic Ocean can be viewed, e.g. from the following netCDF file https://icdc.cen.uni-hamburg.de/fileadmin/user_upload/icdc_Bilder/asi_sic/NSIDC-25km-grid__Arctic-SeaIceOutlook_region_masks__GridCellArea__UHAM-ICDC__fv0.01.nc or https://www.arcus.org/files/page/documents/28201/sio_mask.nc.

Table of contents: sea ice volume; sea ice volume retrieval error

Technical Info: dimension: 105 rows resulting from 15 winters times seven months (October through April); temporalExtent_startDate: 2002-10-01; temporalExtent_endDate: 2017-04-30; temporalResolution: monthly; spatialResolution: none; spatialResolutionUnit: none; horizontalResolutionXdirection: none; horizontalResolutionXdirectionUnit: none; horizontalResolutionYdirection: none; horizontalResolutionYdirectionUnit: none; verticalResolution: none; verticalResolutionUnit: none; verticalStart: none; verticalEnd: none; instrumentName: SIRAL, RA-2; instrumentType: radar altimeter; instrumentLocation: Environmental Satellite (Envisat), CryoSat-2; instrumentProvider: various, ESA 

Methods: https://icdc.cen.uni-hamburg.de/fileadmin/user_upload/ESA_Sea-Ice-ECV_Phase2/SICCI_Phase2_SIV-Retrieval_Report_v02.pdf.

Units: km3; km3

geoLocations: westBoundLongitude: -180.0 degrees East; eastBoundLongitude: 180.0 degrees East; southBoundLatitude: 60.0 degrees North; northBoundLatitude: 90.0 degrees North; geoLocationPlace: Arctic Ocean

Size: 1 file with three semikolon-separated columns; 105 rows

Format: ascii text

DataSources:

http://catalogue.ceda.ac.uk/uuid/f4c34f4f0f1d4d0da06d771f6972f180 (last accessed: 2018-05-20)

http://catalogue.ceda.ac.uk/uuid/ff79d140824f42dd92b204b4f1e9e7c2 (last accessed: 2018-05-20)

https://doi.org/10.5285/f17f146a31b14dfd960cde0874236ee5 (last accessed: 2018-05-20)

https://doi.org/10.15770/EUM_SAF_OSI_0008 (last accessed: 2018-05-20)

Contact: stefan.kern (at) uni-hamburg.de

Web page: https://icdc.cen.uni-hamburg.de/en/esa-cci-sea-ice-ecv0.html

• The snow depths used to convert the altimetric freeboard estimates into sea-ice thickness reflect climatological conditions; it is likely that the influence of inter-annual variation in snow depth on the freeboard-to-thickness conversion are not adequately represented.

• Users are recommended to carefully read the documentation of this data set to understand the limitations arising from the required interpolation of sea-ice thickness and sea-ice concentration values across the observational data gap around the North Pole.

• Users are recommended to read the paper describing freeboard estimation and freeboard-to-thickness conversion methodologies that apply to the product: Paul, et al., The Cryosphere, 12(7), https://doi.org/10.5194/tc-12-2437-2018

• A similar sea-ice volume data set has been derived for the Antarctic. It covers all months of the same period, i.e. years 2002-2017, but is less accurate than in the Arctic due to limitations in the freeboard retrieval; interested users can contact Stefan Kern to obtain this data set.

{"references": ["Paul, et al., The Cryosphere, 12(7), https://doi.org/10.5194/tc-12-2437-2018", "Lavergne, et al., The Cryosphere, 13(1), https://doi.org/10.5194/tc-13-49-2019"]}