N: 66.15 S: -66.15 E: 180 W: -180
Description
Provides L2 high resolution (HR) near real time (NRT; 3-hour latency) altimetry from the Poseidon-4 SAR altimeter on the Sentinel-6A Michael Freilich spacecraft. It contains Sea Surface Height (SSH), Sea Surface Height Anomalies (SSHA) and Significant Wave Height (SWH), along with 1 Hz and 20 Hz Ku-band measurements processed from L1B altimetry including the range, orbital altitude, time, and water vapour. It also includes altimetry corrections, significant wave height and wind-speed from the AMR-C. This standard product release provides the geophysical parameters at both 1 and 20 Hz. The S6A NRT product is analogous to the Jason-3 OGDR product.
Product Summary
Citation
Citation is critically important for dataset documentation and discovery. This dataset is openly shared, without restriction, in accordance with the EOSDIS Data Use and Citation Guidance.
Copy Citation
Documents
DATA CITATION GUIDELINES
GENERAL DOCUMENTATION
Variables
The table below lists the variables contained within a single granule for this dataset. Variables often contain observed or derived geophysical measurements collected from a variety of sources, including remote sensing instruments on satellite and airborne platforms, field campaigns, in situ measurements, and model outputs. The terms variable, parameter, scientific data set, layer, and band have been used across NASA’s Earth science disciplines; however, variable is the designated nomenclature in NASA’s Common Metadata Repository (CMR). Variable metadata attributes such as Name, Description, Units, Data Type, Fill Value, Valid Range, and Scale Factor allow users to efficiently process and analyze the data. The full range of attributes may not be applicable to all variables. Additional information on variable attributes is typically available in the data, user guide, and/or other product documentation.
For questions on a specific variable, please use the Earthdata Forum.
| Name Sort descending | Description | Units | Data Type | Fill Value | Valid Range | Scale Factor | Offset |
|---|---|---|---|---|---|---|---|
| /data_01/mean_sea_surface_sol1 | Mean sea surface height solution 1 above reference ellipsoid (WGS84) | m | int | 2147483647 | N/A | 0.0001 | N/A |
| /data_01/mean_sea_surface_sol1_acc | Mean sea surface height (solution 1) accuracy | m | short | 32767 | N/A | 0.0001 | N/A |
| /data_01/mean_sea_surface_sol1_qual | Interpolation flag (good or bad) for the mean sea surface solution 1 | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/mean_sea_surface_sol2 | Mean sea surface height solution 2 above reference ellipsoid (WGS84) | m | int | 2147483647 | N/A | 0.0001 | N/A |
| /data_01/mean_sea_surface_sol2_acc | Mean sea surface height (solution 2) accuracy | m | short | 32767 | N/A | 0.0001 | N/A |
| /data_01/mean_sea_surface_sol2_qual | Interpolation flag (good or bad) for the mean sea surface solution 2 | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/meteo_map_availability_flag | Possible values are: 0 meaning '2 maps, nominal' (six hours apart), 1 meaning '1 map, extrapolation used', 2 meaning 'no map' | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/model_dry_tropo_cor_measurement_altitude | Dry troposphere correction. Computed from 3d meteorological fields at measurement altitude, at the altimeter time-tag from the interpolation of 2 meteorological fields that surround the altimeter time-tag. A dry tropospheric correction must be added (negative value) to the instrument range measurement to correct it for the dry tropospheric delay of the radar pulse | m | short | 32767 | N/A | 0.0001 | N/A |
| /data_01/model_dry_tropo_cor_zero_altitude | Dry troposphere correction. Computed from 3d meteorological fields at measurement altitude, at the altimeter time-tag from the interpolation of 2 meteorological fields that surround the altimeter time-tag. A dry tropospheric correction must be added (negative value) to the instrument range measurement to correct it for the dry tropospheric delay of the radar pulse | m | short | 32767 | N/A | 0.0001 | N/A |
| /data_01/model_wet_tropo_cor_measurement_altitude | Wet troposphere correction. Computed from 3d meteorological fields at measurement altitude, at the altimeter time-tag from the interpolation of 2 meteorological fields that surround the altimeter time-tag. A wet tropospheric correction must be added (negative value) to the instrument range measurement to correct it for the wet tropospheric delays of the radar pulse | m | short | 32767 | N/A | 0.0001 | N/A |
| /data_01/model_wet_tropo_cor_zero_altitude | Wet troposphere correction. Computed from 3d meteorological fields at measurement altitude, at the altimeter time-tag from the interpolation of 2 meteorological fields that surround the altimeter time-tag. A wet tropospheric correction must be added (negative value) to the instrument range measurement to correct it for the wet tropospheric delays of the radar pulse | m | short | 32767 | N/A | 0.0001 | N/A |
| /data_01/ocean_tide_eq | This value has already been added to the two geocentric ocean tide height values recorded in the product (ocean_tide_sol1 and ocean_tide_sol2). The permanent tide (zero frequency) is not included in this parameter because it is included in the geoid and mean sea surface (geoid, mean_sea_surface_sol1, mean_sea_surface_sol2) | m | short | 32767 | N/A | 0.0001 | N/A |
| /data_01/ocean_tide_non_eq | This parameter is computed as a correction to the parameter ocean_tide_eq; it contains the long-period ocean tide and the long-period load tide components. This value can be added to ocean_tide_eq (or ocean_tide_sol1, ocean_tide_sol2) so that the resulting value models the total ocean tide height including non-equlibrium contributions. | m | short | 32767 | N/A | 0.0001 | N/A |
| /data_01/ocean_tide_sol1 | Solution 1 corresponds to GOT model. Includes the corresponding loading tide (load_tide_sol1) and equilibrium long-period ocean tide height (ocean_tide_eq). The permanent tide (zero frequency) is not included in this parameter because it is included in the geoid and mean sea surface (geoid, mean_sea_surface_sol1, mean_sea_surface_sol2) | m | short | 32767 | N/A | 0.0001 | N/A |
| /data_01/ocean_tide_sol1_qual | Interpolation flag for the ocean tide solution 1 (GOT). Number of interpolated points (4 for good) | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/ocean_tide_sol2 | Solution 2 corresponds to FES model. Includes the corresponding loading tide (load_tide_sol2) and equilibrium long-period ocean tide height (ocean_tide_eq). The permanent tide (zero frequency) is not included in this parameter because it is included in the geoid and mean sea surface (geoid, mean_sea_surface_sol1, mean_sea_surface_sol2) | m | short | 32767 | N/A | 0.0001 | N/A |
| /data_01/ocean_tide_sol2_qual | Interpolation flag for the ocean tide solution 2 (FES). Number of interpolated points (4 for good) | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/off_nadir_pitch_angle_pf | Pitch angle with respect to the nadir pointing, measured by the STRs and post-processed by AOCS or by ground facility. Note: nominal pointing is at satellite nadir (antenna perpendicular to ellipsoid) and corresponds to: pitch = 0 | degrees | int | 2147483647 | N/A | 1.0E-7 | N/A |
| /data_01/off_nadir_roll_angle_pf | Roll angle with respect to the nadir pointing, measured by the STRs and post-processed by Attitude and Orbit Control System(AOCS) or by ground facility. Note: nominal pointing is at satellite nadir (antenna perpendicular to ellipsoid) and corresponds to: roll = 0 | degrees | int | 2147483647 | N/A | 1.0E-7 | N/A |
| /data_01/off_nadir_yaw_angle_pf | Yaw angle with respect to the nadir pointing, measured by the STRs and post-processed by AOCS or by ground facility. Note: nominal pointing is at satellite nadir (antenna perpendicular to ellipsoid) and corresponds to: yaw = 0 | degrees | int | 2147483647 | N/A | 1.0E-7 | N/A |
| /data_01/orbit_type_flag | Orbit type used for the product generation | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/pass_direction_flag | Flag indicating whether the measurement is on an ascending or on a descending pass | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/pole_tide | Calculated using Desai model, with the pole location corrected for a linear drift: in milliarcsec, Xp = 55.0+1.677*dt and Yp = 320.5+3.460*dt where dt is years since 2000.0. | m | short | 32767 | N/A | 0.0001 | N/A |
| /data_01/rad_cloud_liquid_water | Radiometer cloud liquid water content | kg/m^2 | short | 32767 | N/A | 0.01 | N/A |
| /data_01/rad_cloud_liquid_water_qual | Quality flag for the radiometer cloud liquid water content | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/rad_distance_to_land | Shortest distance between main beam measurement and land | m | int | 2147483647 | N/A | 100 | N/A |
| /data_01/rad_land_frac_187 | Fraction of land within the 18.7 GHz main beam. Values are from 0 to 1. | 1 | short | 32767 | N/A | 0.0001 | N/A |
| /data_01/rad_land_frac_238 | Fraction of land within the 23.8 GHz main beam. Values are from 0 to 1. | 1 | short | 32767 | N/A | 0.0001 | N/A |
| /data_01/rad_land_frac_340 | Fraction of land within the 34.0 GHz main beam. Values are from 0 to 1. | 1 | short | 32767 | N/A | 0.0001 | N/A |
| /data_01/rad_rain_flag | Flag indicating if radiometer measurements are invalid due to rain contamination | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/rad_sea_ice_flag | Flag indicating if radiometer measurements are invalid due to sea ice contamination | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/rad_state_oper_flag | Flag indicating if the radiometer is in operational mode or calibration mode | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/rad_surface_type_flag | Flag indicating the validity and type of processing applied to generate the wet troposphere correction (rad_wet_tropo_cor). A value of 0 indicates that open ocean processing is used, a value of 1 indicates coastal processing, and a value of 2 indicates that rad_wet_trop_corr is invalid due to land contamination | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/rad_tb_187 | Equalized brightness temperature measurements at 18.7 GHz. Values are smoothed (along-track averaging has been performed) | K | short | 32767 | N/A | 0.01 | N/A |
| /data_01/rad_tb_187_qual | Quality flag for the 18.7 GHz equalized brightness temperature | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/rad_tb_238 | Equalized brightness temperature measurements at 23.8 GHz. Values are smoothed (along-track averaging has been performed) | K | short | 32767 | N/A | 0.01 | N/A |
| /data_01/rad_tb_238_qual | Quality flag for the 23.8 GHz equalized brightness temperature | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/rad_tb_340 | Equalized brightness temperature measurements at 34.0 GHz. Values are smoothed (along-track averaging has been performed) | K | short | 32767 | N/A | 0.01 | N/A |
| /data_01/rad_tb_340_qual | Quality flag for the 34.0 GHz equalized brightness temperature | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/rad_tmb_187 | Main beam brightness temperature measurements at 18.7 GHz. Values are unsmoothed (along-track averaging has not been performed) | K | short | 32767 | N/A | 0.01 | N/A |
| /data_01/rad_tmb_187_qual | Quality flag for the 18.7 GHz main beam brightness temperature | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/rad_tmb_238 | Main beam brightness temperature measurements at 23.8 GHz. Values are unsmoothed (along-track averaging has not been performed) | K | short | 32767 | N/A | 0.01 | N/A |
| /data_01/rad_tmb_238_qual | Quality flag for the 23.8 GHz main beam brightness temperature | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/rad_tmb_340 | Main beam brightness temperature measurements at 34.0 GHz. Values are unsmoothed (along-track averaging has not been performed) | K | short | 32767 | N/A | 0.01 | N/A |
| /data_01/rad_tmb_340_qual | Quality flag for the 34.0 GHz main beam brightness temperature | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/rad_water_vapor | Radiometer water vapour content | kg/m^2 | short | 32767 | N/A | 0.01 | N/A |
| /data_01/rad_water_vapor_qual | Quality flag for the radiometer water vapor content | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/rad_wet_tropo_cor | Wet tropospheric correction derived from the on-board radiometer and valid over ocean surfaces only. A wet tropospheric correction must be added (negative value) to the instrument range measurement to correct it for the wet tropospheric delays of the radar pulse | m | short | 32767 | N/A | 0.0001 | N/A |
| /data_01/rad_wet_tropo_cor_qual | Quality flag for the radiometer wet troposphere correction | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/rad_wind_speed | Wind speed at 10 m height derived from radiometer measurements. | m/s | short | 32767 | N/A | 0.01 | N/A |