N: 77.6 S: -77.6 E: 180 W: -180
Description
Same as L2_NALT_GDR using predicted values for some auxiliary data, and does not have GIM ionosphere model values. Uses the onboard DORIS orbit ephemeris. Available with latency of < 7 hours. Discrete measurements at nadir for each data downlink, along the ground track. Available in netCDF-4 file format.
This collection is a sub-collection of its parent: https://podaac.jpl.nasa.gov/dataset/SWOT_L2_NALT_OGDR_D
Product Summary
Citation
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USER'S GUIDE
GENERAL DOCUMENTATION
DATA CITATION GUIDELINES
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/ku/swh_ocean_mle3_rms | Compression of Ku band high rate elements is preceded by a detection of outliers. Only valid high-rate values are used to compute this element | m | short | 32767 | N/A | 0.001 | N/A |
| /data_01/ku/swh_ocean_numval | number of valid points used to compute Ku band significant waveheight | count | byte | 127 | 0 to 20 | 1 | N/A |
| /data_01/ku/swh_ocean_rms | Compression of Ku band high rate elements is preceded by a detection of outliers. Only valid high-rate values are used to compute this element | m | short | 32767 | N/A | 0.001 | N/A |
| /data_01/ku/wvf_main_class | Waveform classification : main class selected by classification neural network trained on shape features of the waveforms | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/latitude | Positive latitude is North latitude, negative latitude is South latitude. See SWOT Nadir Altimeter User Handbook. Associated quality flag is orb_state_diode_flag for the OGDR products, orb_state_rest_flag for the IGDR and GDR products | degrees_north | int | 2147483647 | N/A | 1.0E-6 | N/A |
| /data_01/load_tide_got | This value has already been added to the corresponding ocean tide height value recorded in the product (ocean_tide_got). See SWOT Nadir Altimeter User Handbook | m | short | 32767 | N/A | 0.0001 | N/A |
| /data_01/mean_dynamic_topography | See SWOT Nadir Altimeter User Handbook | m | int | 2147483647 | N/A | 0.0001 | N/A |
| /data_01/mean_sea_surface_cnescls | See SWOT Nadir Altimeter User Handbook | m | int | 2147483647 | N/A | 0.0001 | N/A |
| /data_01/mean_sea_surface_cnescls_interp_qual | mean sea surface interpolation flag (CNES/CLS solution) | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/mean_sea_surface_dtu | See SWOT Nadir Altimeter User Handbook | m | int | 2147483647 | N/A | 0.0001 | N/A |
| /data_01/mean_sea_surface_dtu_interp_qual | mean sea surface interpolation flag (DTU solution) | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/mean_wave_period_t02 | t02 mean wave period | s | short | 32767 | N/A | 0.01 | N/A |
| /data_01/meteo_map_availability_flag | Possible values are: 0 meaning ’2 maps, nominal’ (six hours apart), 1 meaning ’2 maps, degraded’ (more than six hours apart), 2 meaning ’1 map, closest map used’, 3 meaning ’no valid map’ | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/model_dry_tropo_cor_measurement_altitude | Computed at coarse DEM altitude (for O&IGDR) or precise measurement altitude (for GDR) 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 to correct this range measurement for dry tropospheric range delays of the radar pulse. See SWOT Nadir Altimeter User Handbook | m | short | 32767 | N/A | 0.0001 | N/A |
| /data_01/model_dry_tropo_cor_zero_altitude | Computed at Mean Sea Level Pressure 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 to correct this range measurement for dry tropospheric range delays of the radar pulse. See SWOT Nadir Altimeter User Handbook | m | short | 32767 | N/A | 0.0001 | N/A |
| /data_01/model_wet_tropo_cor_measurement_altitude | Computed at coarse DEM altitude (for O&IGDR) or precise measurement altitude (for GDR) 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 to correct this range measurement for wet tropospheric range delays of the radar pulse. See SWOT Nadir Altimeter User Handbook | m | short | 32767 | N/A | 0.0001 | N/A |
| /data_01/model_wet_tropo_cor_zero_altitude | Computed at coarse DEM 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 to correct this range measurement for wet tropospheric range delays of the radar pulse. See SWOT Nadir Altimeter User Handbook | m | short | 32767 | N/A | 0.0001 | N/A |
| /data_01/numtotal_20hz_measurement | Total number of 20 Hz measurements associated to the 1 Hz measurement | N/A | byte | 127 | N/A | 1 | 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_got and ocean_tide_fes). 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_cnescls). See SWOT Nadir Altimeter User Handbook | m | short | 32767 | N/A | 0.0001 | N/A |
| /data_01/ocean_tide_fes | Includes the equilibrium long-period ocean tide height (ocean_tide_eq) and only the short-period part of the corresponding loading tide (load_tide_fes). 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_cnescls). To get the total geocentric tide height (FES solution), do: ocean_tide_fes + ocean_tide_non_eq. See SWOT Nadir Altimeter User Handbook | m | int | 2147483647 | N/A | 0.0001 | N/A |
| /data_01/ocean_tide_fes_interp_qual | 0 = 4 points over ocean; 1 = less than 4 points; 2 = extrapolated points | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/ocean_tide_got_interp_qual | 0 = 4 points over ocean; 1 = less than 4 points; 2 = extrapolated points | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/orb_state_diode_flag | 0 = Accurate orbit (0 - 5 cm radial), 1 = Good orbit (5 - 10 cm radial), 2 = Moderate orbit (10 - 15 cm radial), 4-8 = Potentially degraded orbit (> 15 cm radial), 9 = Degraded orbit (e.g., as during maneuver) | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/orb_state_rest_flag | 0 characterizes a mission operations orbit that is computed during a maneuver period, 1 stands for an adjusted mission operations orbit, 2 stands for an extrapolated mission operations orbit, 3 stands for an adjusted (preliminary/precise) orbit, 4 indicates that the (preliminary/precise) orbit is estimated during a maneuver period, 5 indicates that the (preliminary/precise) orbit is interpolated over a tracking data gap, 6 means that the (preliminary/precise) orbit is extrapolated for a duration less than 1 day, 7 means that the (preliminary/precise) orbit is extrapolated for a duration that ranges from 1 day to 2 days, 8 means that the (preliminary/precise) orbit is extrapolated for a duration larger than 2 days, or that the orbit is extrapolated just after a maneuver, 9 stands for the DORIS DIODE navigator orbit. The nominal value is 3 | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/pole_tide | See SWOT Nadir Altimeter User Handbook | m | short | 32767 | N/A | 0.0001 | N/A |
| /data_01/rad_side_1_distance_to_land | Shortest distance between nadir sub-satellite point and land | m | int | 2147483647 | N/A | 1 | N/A |
| /data_01/rad_side_1_land_frac_187 | ratio between 0 and 1 | 1 | short | 32767 | N/A | 0.01 | N/A |
| /data_01/rad_side_1_land_frac_238 | ratio between 0 and 1 | 1 | short | 32767 | N/A | 0.01 | N/A |
| /data_01/rad_side_1_rain_flag | See SWOT Nadir Altimeter User Handbook | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/rad_side_2_land_frac_187 | ratio between 0 and 1 | 1 | short | 32767 | N/A | 0.01 | N/A |
| /data_01/rad_side_2_land_frac_340 | ratio between 0 and 1 | 1 | short | 32767 | N/A | 0.01 | N/A |
| /data_01/rad_side_2_rain_flag | See SWOT Nadir Altimeter User Handbook | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/rad_side_2_surface_type_flag | radiometer surface type from second radiometer | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/rad_tb_187_qual | quality flag for 1 Hz radiometer data: 18.7 GHz brightness temperature | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/rad_tb_340 | Brightness temperatures are along-track averaged | K | int | 2147483647 | N/A | 0.01 | N/A |
| /data_01/rad_tmb_187 | Brightness temperatures are unsmoothed (along-track averaging has not been performed on the brightness temperatures) | K | int | 2147483647 | N/A | 0.01 | N/A |
| /data_01/rad_tmb_238 | Brightness temperatures are unsmoothed (along-track averaging has not been performed on the brightness temperatures) | K | int | 2147483647 | N/A | 0.01 | N/A |
| /data_01/rad_tmb_340 | Brightness temperatures are unsmoothed (along-track averaging has not been performed on the brightness temperatures) | K | int | 2147483647 | N/A | 0.01 | N/A |
| /data_01/rad_wet_tropo_cor_interp_qual | See SWOT Nadir Altimeter User Handbook | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/rad_wind_speed | Should not be used over land. See SWOT Nadir Altimeter User Handbook | m/s | short | 32767 | N/A | 0.01 | N/A |
| /data_01/rain_flag | See SWOT Nadir Altimeter User Handbook | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/rain_rate | See SWOT Nadir Altimeter User Handbook | mm/h | short | 32767 | N/A | 0.01 | N/A |
| /data_01/sea_ice_concentration_interp_qual | 0 = interpolation from 4 points; 1 = interpolation from less than 4 points | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/surface_classification_flag | Computed from a mask built with MODIS and GlobCover data | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/surface_slope_cor | The surface slope correction model aims to improve the accuracy of mean sea surface topography models as well as marine gravity models. See SWOT Nadir Altimeter User Handbook | m | int | 2147483647 | N/A | 0.0001 | N/A |
| /data_01/wave_model_interp_qual | 0 = interpolation from 4 points; 1 = interpolation from less than 4 points | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/wave_model_map_availability_flag | Possible values are: 0 meaning ’2 maps, nominal’ (three hours apart), 1 meaning ’2 maps, degraded’ (more than three hours apart), 2 meaning ’1 map, closest map used’, 3 meaning ’no valid map’ | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/wind_speed_alt | Should not be used over land. See SWOT Nadir Altimeter User Handbook. A calibration bias of +0.39 dB has been added to the Ku band backscatter coefficient (/data_01/ku/sig0_ocean) before computing the wind speed | m/s | short | 32767 | N/A | 0.01 | N/A |
| /data_01/wind_speed_alt_adaptive | Should not be used over land. See SWOT Nadir Altimeter User Handbook. A calibration bias of +0.08 dB has been added to the Ku band backscatter coefficient (/data_01/ku/sig0_adaptive) before computing the wind speed | m/s | short | 32767 | N/A | 0.01 | N/A |
| /data_20/altitude | Altitude of satellite above the reference ellipsoid | m | int | 2147483647 | N/A | 0.0001 | 800000 |