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_2.0
Product Summary
Citation
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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/rad_side_1_sea_ice_flag | See SWOT Nadir Altimeter User Handbook | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/rad_side_1_surface_type_flag | radiometer surface type from first radiometer | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/rad_side_2_distance_to_land | Shortest distance between nadir sub-satellite point and land | m | int | 2147483647 | 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_238 | 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_sea_ice_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 | Brightness temperatures are along-track averaged | K | int | 2147483647 | N/A | 0.01 | 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_238 | Brightness temperatures are along-track averaged | K | int | 2147483647 | N/A | 0.01 | N/A |
| /data_01/rad_tb_238_qual | quality flag for 1 Hz radiometer data: 23.8 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_tb_340_qual | quality flag for 1 Hz radiometer data: 34 GHz brightness temperature | N/A | byte | 127 | N/A | 1 | 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_water_vapor | Should not be used over land | kg/m^2 | short | 32767 | N/A | 0.1 | N/A |
| /data_01/rad_wet_tropo_cor | 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 | m | short | 32767 | N/A | 0.0001 | 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 | percentage between 0 and 100 | 1 | 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/sig0_cor_atm_source | Flag indicating whether the radiometer data or the climatological values from meteorological model (ECMWF backup solution) have been used to compute the atmospheric sigma0 correction | N/A | byte | 127 | N/A | 1 | N/A |
| /data_01/solid_earth_tide | Calculated using Cartwright and Tayler tables and consisting of the second and third degree constituents. The permanent tide (zero frequency) is not included. See SWOT Nadir Altimeter User Handbook | m | short | 32767 | N/A | 0.0001 | N/A |
| /data_01/sst | sea surface temperature | K | short | 32767 | N/A | 0.01 | 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 shall not be used with the mean sea surface (mean_sea_surface_cnescls or mean_sea_surface_dtu) provided in the product. See SWOT Nadir Altimeter User Handbook | m | int | 2147483647 | N/A | 0.0001 | N/A |
| /data_01/time | Time of measurement in seconds in the UTC time scale since 1 Jan 2000 00:00:00 UTC. [tai_utc_difference] is the difference between TAI and UTC reference time (seconds) for the first measurement of the data set. If a leap second occurs within the data set, the attribute [leap_second] is set to the UTC time at which the leap second occurs | seconds since 2000-01-01 00:00:00.0 | double | N/A | N/A | 1 | N/A |
| /data_01/time_tai | Time of measurement in seconds in the TAI time scale since 1 Jan 2000 00:00:00 TAI. This time scale contains no leap seconds. The difference (in seconds) with time in UTC is given by the attribute [time:tai_utc_difference] | seconds since 2000-01-01 00:00:00.0 | double | 1.844674407371E+19 | N/A | 1 | 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 +0.06 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_01/wind_speed_alt_mle3 | Should not be used over land. See SWOT Nadir Altimeter User Handbook. A calibration bias of +0.109 dB has been added to the Ku band backscatter coefficient (/data_01/ku/sig0_ocean_mle3) before computing the wind speed | m/s | short | 32767 | N/A | 0.01 | N/A |
| /data_01/wind_speed_mod_u | Computed at the altimeter time-tag from the interpolation of 2 meteorological fields that surround the altimeter time-tag. See SWOT Nadir Altimeter User Handbook | m/s | short | 32767 | N/A | 0.01 | N/A |
| /data_01/wind_speed_mod_v | Computed at the altimeter time-tag from the interpolation of 2 meteorological fields that surround the altimeter time-tag. See SWOT Nadir Altimeter User Handbook | 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 |
| /data_20/alt_state_acq_mode_flag | 8 = autonomous acquisition / tracking, 9 = autonomous DIODE acquisition / tracking, 10 = DIODE + Digital Elevation Model tracking | N/A | byte | 127 | N/A | 1 | N/A |
| /data_20/alt_state_track_trans_flag | 20 Hz altimeter state flag: tracking automatic transition | N/A | byte | 127 | N/A | 1 | N/A |
| /data_20/angle_of_approach_to_coast | Angle of approach to the closest coast. 0 is parallel to the coast with the land on the right. Positive values indicate the satellite is approaching the land. Negative values indicate the satellite is leaving the land. Values close to +/-180 degrees have the land on the left | degrees | short | 32767 | N/A | 0.01 | N/A |
| /data_20/c/ice2_qual | ice-2 retracking quality flag | N/A | byte | 127 | N/A | 1 | N/A |
| /data_20/c/mqe_ice2 | Mean Quadratic Error between the waveforms samples and the corresponding model samples built from the ice-2 retracking outputs | 1 | int | 2147483647 | N/A | 1.0E-5 | N/A |
| /data_20/c/mqe_ocean | Mean Quadratic Error between the waveforms samples and the corresponding model samples built from the ocean retracking outputs | 1 | short | 32767 | N/A | 0.0001 | N/A |
| /data_20/c/num_iterations_ocean | 20 Hz number of iterations of the ocean retracking in C band | count | byte | 127 | N/A | 1 | N/A |
| /data_20/c/peakiness | 20 Hz peakiness on C band waveforms | 1 | int | 2147483647 | N/A | 0.001 | N/A |
| /data_20/c/range_ice2 | Distance antenna-COG (/data_01/range_cor_cog), USO drift correction (/data_01/range_cor_uso), internal path correction (/data_01/c/range_cor_internal_path), Doppler correction (/data_01/c/range_cor_doppler) and system bias included | m | int | 2147483647 | N/A | 0.0001 | 800000 |