Dataset
ESA Sea Ice Climate Change Initiative (Sea_Ice_cci): Drift-aware sea-ice thickness for the Northern Hemisphere from CryoSat-2, v1.0
Abstract
This dataset provides daily drift-aware sea ice freeboard and thickness maps, using satellite altimetry data from CryoSat-2, covering the entire Arctic sea ice domain. Daily files are provided during boreal winter seasons (October to April).
Neglecting sea ice drift when generating monthly sea ice thickness maps from satellite altimetry will cause blurring of the spatial distribution of ice thickness. This dataset synergizes sea ice freeboard and thickness information from satellite altimetry with sea ice drift estimates from passive microwave satellite sensors. Individual parcels of satellite altimeter measurements are advected daily over a time span of one month to obtain drift-aware sea ice freeboard and thickness maps. Because of the drift correction, this allows the determination of sea ice that was overflown by the satellite multiple times, and therefore the estimation of growth rates and changes in the sea ice thickness distribution due to deformation and thermodynamic ice growth between satellite overflights. With the estimation of sea ice growth, measurements can be corrected for the time offset between the acquisition day and the target day, the day to which all measurements within a month are projected.
These data have been produced as part of the European Space Agency (ESA)'s Climate Change Initiative (CCI) programme, as part of the ESA CCI Sea Ice project.
Details
| Previous Info: |
No news update for this record
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| Previously used record identifiers: |
No related previous identifiers.
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| Access rules: |
Public data: access to these data is available to both registered and non-registered users.
Use of these data is covered by the following licence(s): https://artefacts.ceda.ac.uk/licences/specific_licences/esacci_seaice_terms_and_conditions.pdf When using these data you must cite them correctly using the citation given on the CEDA Data Catalogue record. |
| Data lineage: |
Data were processed by the ESA CCI Sea Ice project team and were supplied to CEDA in the context of the ESA CCI Open Data Portal. The following organisations were involved in the Sea_Ice_CCI project which resulted in production of this dataset: NORCE Norwegian Research Centre, Norwegian Meteorological Institute, Alfred Wegener Institute. |
| Data Quality: |
See the Sea Ice CCI documentation for information on data quality.
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| File Format: |
NetCDF
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Related Documents
Process overview
| Title | Computation for ESA Sea Ice Climate Change Initiative (Sea_Ice_cci): Retrieval of drift-aware sea-ice thickness from radar altimetry and passive microwave drift data |
| Abstract | The method used to extract sea-ice thickness from radar altimetry data is based on the pioneering work of Peacock and Laxon, 2004; Laxon et al., 2003 for the ERS-2 mission. The method involves separating the radar echoes returning from the ice floes from those returning from the sea surface in the leads between the floes. This step of a surface-type classification is crucial and allows for a separate determination of the ice floe and sea-surface heights. The freeboard that is the elevation of the ice upper side (or ice/snow interface) above the sea level can then be computed by deducting the interpolated sea-surface height at the floe location from the height of the floe. Using the freeboard and additional snow load information, sea-ice thickness is then computed along the satellite track. To account for sea-ice motion, the along-track thickness estimates are combined with drift data from passive microwave sensors (Lavergne & Down, 2023). Individual measurement parcels are advected daily over a one-month period, resulting in drift-aware sea-ice thickness maps that reflect the evolving distribution of the ice. |
| Input Description | None |
| Output Description | None |
| Software Reference | None |
- units: 1
- var_id: sea_ice_thickness_hist
- long_name: Counts per thickness class for classes between 0 m and 10 m with 0.25m bin size
- var_id: crs
- long_name: NSIDC EASE-Grid 2.0 North
- units: 1
- var_id: region_code
- long_name: NSIDC region mask v2
- units: m
- standard_name: sea_ice_thickness standard_error
- var_id: sea_ice_thickness_total_unc
- long_name: combined sea ice thickness uncertainty
- units: m
- var_id: dist_acquisition
- long_name: distance between target day and day of data acquisition location
- units: m
- var_id: hist_bins
- long_name: histogram bin centers
- units: m
- var_id: sea_ice_thickness_growth_interpolated
- long_name: interpolated rate of change in sea ice thickness per day
- units: m
- var_id: sea_ice_thickness_growth
- long_name: rate of change in sea ice thickness per day
- units: percent
- standard_name: sea_ice_area_fraction
- var_id: sea_ice_concentration
- long_name: sea ice concentration
- units: m
- standard_name: sea_ice_thickness
- var_id: sea_ice_thickness
- long_name: sea ice thickness
- units: m
- standard_name: sea_ice_thickness standard_error
- var_id: sea_ice_thickness_drift_unc
- long_name: sea ice thickness uncertainty associated with the ice drift correction
- units: m
- standard_name: sea_ice_thickness standard_error
- var_id: sea_ice_thickness_l2_unc
- long_name: sea ice thickness uncertainty associated with the level2 product
- units: m
- var_id: sea_ice_thickness_growth_unc
- long_name: sea ice thickness uncertainty associated with the rate of change in sea ice thickness per day
- units: m
- standard_name: sea_ice_thickness
- var_id: sea_ice_thickness_std
- long_name: standard deviation of sea ice thickness estimates within parcel
- units: m
- standard_name: surface_snow_thickness_where_sea_ice
- var_id: snow_depth
- long_name: thickness of the snow layer
- var_id: time_bnds
- long_name: time bounds
- units: days
- var_id: time_offset_acquisition
- long_name: time since data acquisition
- units: m
- standard_name: projection_x_coordinate
- long_name: x coordinate of projection (eastings)
- var_id: xc
- units: m
- standard_name: projection_y_coordinate
- long_name: y coordinate of projection (northings)
- var_id: yc
Co-ordinate Variables
- units: degrees_north
- standard_name: latitude
- var_id: latitude
- long_name: latitude of grid cell center
- units: degrees_east
- standard_name: longitude
- var_id: longitude
- long_name: longitude of grid cell center
- long_name: time
- standard_name: time
- var_id: time
- units: seconds
Temporal Range
2010-11-01T00:00:00
2020-04-30T00:00:00
Geographic Extent
89.8417° |
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-179.8671° |
179.8671° |
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16.6239° |