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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
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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
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l2p-trajectory-doc

Data LevelLevel-2 Post-Processed (L2P)
Data PeriodDaily (between 00:00:00 and 23:59:59.999 UTC)
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 example

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

Space-Time Grid

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l3c-grid-doc

Data Level

Level-3 Colocated (L3C)

Data Period

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

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 and 23:59:59.999 UTC last day)

SummaryGridded geophysical parameters, their uncertainties, retrieval area statistics and flags 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
Time / 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

Weekly Gridded (L3C) data example

Figure: Example of weekly gridded sea-ice thickness product

Monthly gridded (L3C) data example

Figure: Example of monthly gridded sea-ice thickness product