Minimize Environmental Parameters

The environmental parameters are computed at Level-2 processing.

  • U and V components of the model wind vector computed from the interpolation of two meteorological fields.
  • Altimeter wind speed using ECMWF conversion table.
  • Water vapour content using the radiometer brightness temperature.
  • Liquid vapour content using the radiometer brightness temperature.
  • Total electron content. 
 

PARAMETER

Total Electron Content

NETCDF NAME

total_electron_content_[x1]_[x2]
[x1]: 1 Hz or 20 Hz data rates
[x2]: Ku-band or C-band

DESCRIPTION

The ALT_COR_RAN_05 algorithm computes the total electron content

UNITS

1010 counts

DATA SET AVAILABILITY

Reduced: none
Standard: 1 Hz
Enhanced: 1 Hz

OPERATING MODE AVAILABILITY

LRM and SAR

DATA ORIGIN

1 Hz Ku/C-bands: ALT_COR_RAN_05
20 Hz Ku-band: none
20 Hz C-band: none

ADDITIONAL INFORMATION

None

PARAMETERS RELATED

None

PARAMETER DETAILED DESCRIPTION

ESA's Global Land and Ocean Mission for GMES Operational Services

Table 1. Total electron content

 
 

PARAMETER

Altimeter Wind Speed Over Ocean

NETCDF NAME

wind_speed_alt_[x1]_[x2]
[x1]: 1 Hz or 20 Hz data rates
[x2]: Ku-band or C-band

DESCRIPTION

The ALT_PHY_WIN_01 algorithm computes the 10 m wind speed using a table that converts corrected Ku-band backscatter coefficient and the Ku-band significant wave height to wind speed. This table was created by ECMWF. Do not use this value over land surfaces.

UNITS

10-2 m/s

DATA SET AVAILABILITY

Reduced: 1 Hz
Standard: 1 Hz
Enhanced: 1 Hz

OPERATING MODE AVAILABILITY

LRM only

DATA ORIGIN

1 Hz Ku/C-bands: ALT_PHY_WIN_020
1 Hz Ku-band: none
20 Hz C-band: none

ADDITIONAL INFORMATION

None

PARAMETERS RELATED

None

PARAMETER DETAILED DESCRIPTION

ESA's Global Land and Ocean Mission for GMES Operational Services

Table 2. Altimeter wind speed

 
 

PARAMETER

Water Vapour Content Measured by Radiometer

NETCDF NAME

rad_water_vapor_[x1]_[x2]

[x1]: 1 Hz or 20 Hz data rates

[x2]: Ku-band or C-band

DESCRIPTION

The RAD_PHY_GEN_01 algorithm computes water vapour content from the radiometer 23.8 GHz and 36.5 GHz brightness temperatures (interpolated at the SRAL time-tag) and from the Ku-band sigma0, using a neural network function.

UNITS

10-1 kg/m2

DATA SET AVAILABILITY

Reduced: 1 Hz

Standard: 1 Hz

Enhanced: 1 Hz

OPERATING MODE AVAILABILITY

LRM and SAR

DATA ORIGIN

1 Hz Ku/C-bands: RAD_PHY_GEN_01

20 Hz Ku-band: none

20 Hz C-band: none

ADDITIONAL INFORMATION

None

PARAMETERS RELATED

None

PARAMETER DETAILED DESCRIPTION

ESA's Global Land and Ocean Mission for GMES Operational Services

Table 3. Radiometer water vapour content


 

PARAMETER

Liquid Water Content Measured by Radiometer

NETCDF NAME

rad_liquid_water_[x1]_[x2]
[x1]: 1 Hz or 20 Hz data rates
[x2]: Ku-band or C-band

DESCRIPTION

The RAD_PHY_GEN_01 algorithm computes atmosphere cloud liquid water content from the radiometer 23.8 GHz and 36.5 GHz brightness temperatures (interpolated at the SRAL time-tag) and from the Ku-band sigma0, using a neural network function

UNITS

10-2 kg/m2

DATA SET AVAILABILITY

Reduced: 1 Hz
Standard: 1 Hz
Enhanced: 1 Hz

OPERATING MODE AVAILABILITY

LRM and SAR

DATA ORIGIN

1 Hz Ku/C-bands: RAD_PHY_GEN_01
20 Hz Ku-band: none
20 Hz C-band: none

ADDITIONAL INFORMATION

None

PARAMETERS RELATED

None

PARAMETER DETAILED DESCRIPTION

ESA's Global Land and Ocean Mission for GMES Operational Services

Table 4. Radiometer liquid water content

 

 

PARAMETER

U and V Components of the Model Wind Vector

NETCDF NAME

wind_speed_mod_u_[x1]_[x2]
wind_speed_mod_v_[x1]_[x2]
[x1]: 1 Hz or 20 Hz data rates
[x2]: Ku-band or C-band

DESCRIPTION

The GEN_COR_RAN_01 algorithm computes the 10 m wind vector components U (zonal component) and V (meridian component) at the altimeter measurement by a linear interpolation in time between two consecutive (6 hours apart) model data files. ECMWF (European Centre for Medium-Range Weather Forecasts) provides these meteorological data files.

UNITS

10-2 m/s

DATA SET AVAILABILITY

Reduced: none
Standard: 1 Hz
Enhanced: 1 Hz

OPERATING MODE AVAILABILITY

LRM and SAR

DATA ORIGIN

1 Hz Ku/C-bands: GEN_COR_RAN_01
20 Hz Ku-band: none
20 Hz C-band: none

ADDITIONAL INFORMATION

None

PARAMETERS RELATED

None

PARAMETER DETAILED DESCRIPTION

ESA's Global Land and Ocean Mission for GMES Operational Services

Table 5. Model wind vector