codede-data

Sentinel-3 L2 SRAL

SRAL (SAR Radar Altimeter) Level-2 products are based on the respective Level-1 products. The first function of the Level-2 processing chain is to apply different re-tracking algorithms to calculate e.g. the final altimeter range, backscatter coefficient and wind speed over ocean

There are two types of Level-2 products according to the surface:

  • WAT: Water products, generated by the Marine Centre
  • LAN: Land products, generated by the Land Centres

Algorithms

The first function of the Level-2 processing chain is to apply different re-tracking algorithms to Level-1 waveforms to calculate the final altimeter range, backscatter coefficient, wind speed over ocean and SWH. There are different types of re-tracking algorithms according to the type of waveforms re-tracked (ocean, ice, sea-ice).

The second function of the Level-2 processing chain is to compute and apply all geophysical corrections to the measurements. Examples of geophysical correction algorithms are the tides or the reference surface used (e.g. the geoid).

There are three types of algorithms in the Level-2 processing chain:

  • Algorithms computing time-derived geophysical/environmental parameters
  • Algorithms computing retracking and computing physical parameters
  • Algorithms performing altimeter/radiometer geophysical processing.

Products

A Level-2 SRAL/MWR product contains three netCDF files:

  • Reduced (//red//) data file, containing a subset of the main 1 Hz Ku-band parameters
  • Standard (//std//) data file containing the standard 1 Hz and 20 Hz Ku and C-band parameters
  • Enhanced (//enh//) data file containing the standard 1 Hz and 20 Hz Ku and C-band parameters, the waveforms and the associated parameters necessary to reprocess the data (at least in LRM mode).

Each of these three files contains one or more data sets from among the following:

  • 20 Hz LRM/SAR_Ku data set: Set of 20 Hz Ku-band parameters issued from SRAL tracking measurements performed in LRM and SAR modes
  • 20 Hz LRM/SAR_C data set: Set of 20 Hz C-band parameters issued from SRAL tracking measurements performed in LRM and SAR modes
  • 1 Hz LRM/SAR_Ku/C data set: Set of 1 Hz Ku/C-band parameters issued from SRAL tracking measurements performed in LRM and SAR modes.

On this platform the NRT (near real time), STC (short time critical) and NTC (non time critical) products are available.

Availability

  • Germany: 2016-03 - now
  • Europe: 2016-03 - now
  • Global: 2016-03 - now

Usage requirements

There are certain requirements that must be met for use. Some data or services require an individual application. For more information, please contact CODE-DE Support.

Required? Remark
Registration on CODE-DE Yes ---
Cloud resources on CODE-DE No ---
Individual request No ---

Access

Depending on the environment and the intended use, there are several ways to access the data:

  • EO Browser: -
  • Data Explorer:
    • Data Catalogue: CODE-DE or CREODIAS
  • Path to repository on a Virtual Machine:
    • /codede/Sentinel-3/SRAL/SR_2_LAN
    • /codede/Sentinel-3/SRAL/SR_2_WAN

More information

Further information on this product can also be found on the following external pages:

Terms of use

Use of the product is subject to the following terms of use: