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Excerpt

The sea-ice thickness processing chain generates higher level data products (such as maps) from measurements along the ground track of the satellite. Sea-ice thickness information is therefore available at different data levels that differ in the extent and resolution of the corresponding dataset.

Table of Contents
absoluteUrltrue
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Single Orbit


Data LevelLevel-2 Intermediate (L2i)
Data PeriodIndividual (for each orbit segment)
SummaryGeophysical variables and error flags at full resolution of the altimeter (typically 300 meter).
ParametersAll fields are per single altimeter data point
  • time-orbit (time, longitude, latitude)
  • geophysical parameters and their uncertainties
  • flag (surface_type, radar mode)
Info

l2i data products are not publically available due to their data volume but can be made available upon request

Image Added

Figure: Example of sea-ice thickness along a single orbit at along-track resolution


Daily Trajectory Summary
Anchor
l2p-trajectory-doc
l2p-trajectory-doc

Data LevelLevel-2 Post-Processed (L2P)
Data PeriodDaily (between 00:00:00 and 23:59:59.999 UTC
)AvailabilityCryoSat version 2.0+Data Format

netCDF v4 (Climate and forecast  conventions)

Filenaming
l2p-awi-seaice-{mission}-{timeliness}-{hemisphere}-{yyyy}{mm}{dd}-{version}.nc
(e.g. l2p-awi-seaice-cryosat2-ntc-nh-20101101-v2.0.nc
)
Summary

Collection of daily along-track geophysical parameters and their uncertainties at full resolution of the altimeter (typically 300 meter).  

Product only includes data points with valid freeboard measurements, though the point spacing of the data is potentially irregular.

ParametersAll fields are per single altimeter data point
.

  • time-orbit (time
  • , longitude
  • latitude
  • radar mode
  • radar freeboard + uncertainty
  • freeboard + uncertainty
  • snow depth + uncertainty
  • snow density + uncertainty
  • sea ice type + uncertainty
  • sea ice thickness + uncertainty
    • , latitude)
    • geophysical parameters and their uncertainties
    • flag (radar mode)

    Daily L2P product exampleImage Modified

    Figure: Example of daily sea-ice thickness point measurements at along-track resolution

    Space-Time Grid

    Anchor
    l3c-grid-doc
    l3c-grid-doc

    Weekly Gridded

    Data Level

    Level-3 Colocated (L3C)

    Data Period

    Weekly (

    between

    Monday 00:00:00 and Sunday 23:59:59.999 UTC)

    AvailabilityCryoSat version 2.0+Data Format

    netCDF v4 (Climate and forecast  conventions)

    Filenaming
    l3c-awi-seaice-{mission}-{timeliness}-{grid}-{yyyy}{mm}{dd}-{yyyy}{mm}{dd}-{version}.nc 

    (e.g. l3c-awi-seaice-cryosat2-ntc-nh25kmEASE2-20101101-20101107-fv2.0.nc)

    SummaryWeekly gridded geophysical parameters, their uncertainties, retrieval area statistics and flagsGrid

    EASE-2 North (Lambert Azimuthal Equal Area)

    Projection:

    +proj=laea +lon_0=0 +datum=WGS84 +ellps=WGS84 +lat_0=90.0

    Resolution: 25 km (Arctic)

    ParametersTime / Geolocation:
    • longitude (grid cell center notation)
    • latitude (grid cell center notation)
    • grid x position in projection coordinates
    • grid y position in projection coordinates
    • time bounds
    • reference time

    Geophysical fields (per grid cell)

    • mean sea surface
    • sea ice concentration
    • sea surface anomaly + uncertainty
    • radar freeboard + uncertainty
    • freeboard + uncertainty
    • snow depth + uncertainty
    • snow density + uncertainty
    • sea ice type + uncertainty
    • sea ice thickness + uncertainty

    Flags (per grid cell)

    • Number of all input data points
    • Number of valid (ice or lead) data points
    • Fraction of ice data points per valid data points
    • Fraction of lead data points per valid data points
    • Retrieval status flag
    • Retrieval quality flag

    Monthly (between 00:00:00 first day and 23:59:59.999 UTC last day of the month)

    Custom (between 00:00:00 first day

    Weekly Gridded (L3C) data exampleImage Removed

    Figure: Example of weekly gridded sea-ice thickness product

    Monthly Gridded

    Data LevelLevel-3 Colocated (L3C)Data PeriodMonthly (between first day 00:00:00

    and 23:59:59.999 UTC last day

    of month)Availability

    CryoSat version 1.2 (different file format)

    CryoSat version 2.0+

    Data FormatnetCDF v4 (Climate and forecast  conventions

    )

    Filenaming

    l3c-awi-seaice-{mission}-{timeliness}-{grid}-{yyyy}{mm}{dd}-{version}.nc 

    (e.g. l3c-awi-seaice-cryosat2-ntc-nh25kmEASE2-201011-fv2.0.nc)

    SummaryGridded
    SummaryMonhtly gridded
    geophysical parameters, their uncertainties, retrieval area statistics and flags
    Grid

    EASE-2 North (Lambert Azimuthal Equal Area)

    Projection:

    +proj=laea +lon_0=0 +datum=WGS84 +ellps=WGS84 +lat_0=90.0

    Resolution: 25 km (Arctic)

    ParametersTime / Geolocation:
    • longitude (grid cell center notation)
    • latitude (grid cell center notation)
    • grid x position in projection coordinates
    • grid y position in projection coordinates
    • time bounds
    • reference time

    Geophysical fields (per grid cell)

    • mean sea surface
    • sea ice concentration
    • sea surface anomaly + uncertainty
    • radar freeboard + uncertainty
    • freeboard + uncertainty
    • snow depth + uncertainty
    • snow density + uncertainty
    • sea ice type + uncertainty
    • sea ice thickness + uncertainty

    Flags (per grid cell)

    • Number of all input data points
    • Number of valid (ice or lead) data points
    • Fraction of ice data points per valid data points
    • Fraction of lead data points per valid data points
    • Retrieval status flag
    • Retrieval quality flag
    on a space-time grid
    ParametersAdd variables are given per grid cell, except time bound and reference time
    • geolocation (longitude/latitude, projection coordinates)
    • geophysical parameters and their uncertainties
    • grid cell statistics (number of points, surface type detection fractions, ....)
    • flags (retrieval status & quality flag)
    • land mask and region code

    Weekly Gridded (L3C) data exampleImage Added

    Figure: Example of weekly gridded sea-ice thickness product

    Monthly gridded (L3C) data exampleImage Added

    Monthly gridded (L3C) data exampleImage Removed

    Figure: Example of monthly gridded sea-ice thickness product