TOPEX/POSEIDON Geophysical Data Record Version F

(TOPEX_POSEIDON_GDR_F)

Information
Coverage
Data Access
Variables
Documentation
Citation

Version	F
Processing Level	2
Start/Stop Date	1992-Oct-13 to 2005-Oct-04
Short Name	TOPEX_POSEIDON_GDR_F
Description	The TOPEX/POSEIDON Geophysical Data Record (GDR) contains global coverage altimeter data. The objective of the TOPEX/POSEIDON mission, launched in August 1992, is to determine ocean topography with a sea surface height measurement precision of 3 cm and a sealevel measurement accuracy of 13 cm. The dataset contains measurements from two altimeters, a NASA dual frequency (Ku and C band) instrument similar to the Geosat altimeter, and a French space agency (CNES) instrument which is a proof-of-concept solid-state altimeter (Ku band). It also contains Sea Surface Height (SSH), significant wave height, ionospheric correction, tides and other geophysical corrections. It is emphasized that this product is considered research data because of the form and content of the data. The data consist entirely of files comprising headers and data records which contain over a hundred parameters for each second. It is swath data and there are no images. Analysis software is the responsibility of the user. Calculation of sea surface height anomalies from the altimeter range and environmental corrections is the responsibility of the user. The data are arranged in 10 day cycles that are separated into 254 passes, each about 56 minutes.
DOI	10.5067/TPXPS-GDRF1
Measurement	OCEANS > SEA SURFACE TOPOGRAPHY > SEA SURFACE HEIGHT OCEANS > OCEAN WAVES > SIGNIFICANT WAVE HEIGHT
Platform/Sensor	TOPEX/POSEIDON Platform Name: Ocean Topography Experiment (TOPEX/POSEIDON) / ALT (TOPEX) SENSOR Name: TOPEX Radar Altimeter (ALT (TOPEX)) TOPEX/POSEIDON Platform Name: Ocean Topography Experiment (TOPEX/POSEIDON) / TMR SENSOR Name: TOPEX Microwave Radiometer (TMR)
Project	Ocean Topography Experiment (TOPEX/POSEIDON)
Data Provider	Publisher: NASA/JPL/PODAAC Creator: TOPEX/Poseidon Release Date: 2023-Mar-09
Format	netCDF-4
Keyword(s)	topex, poseidon, topex/poseidon, radar altimeter, microwave radiometer, ocean, sea level, ssh

Questions related to this dataset? Contact podaac@podaac.jpl.nasa.gov

Resolution Temporal Resolution: 1 minute - < 1 hour Coverage North Bounding Coordinate: 66 degrees South Bounding Coordinate: -66 degrees West Bounding Coordinate: -180 degrees East Bounding Coordinate: 180 degrees Time Span: 1992-Oct-13 to 2005-Oct-04

DIRECT ACCESS
Browse Granule Listing
https://cmr.earthdata.nasa.gov/virtual-directory/collections/C2599212091-POCLOUD
Search Granules
https://search.earthdata.nasa.gov/search/granules?p=C2599212091-POCLOUD
T/P Cycle Start Times
https://archive.podaac.earthdata.nasa.gov/podaac-ops-cumulus-docs/topex/open/L2/docs/tp_cyclelist.txt
T/P Safehold Start and Stop Times
https://archive.podaac.earthdata.nasa.gov/podaac-ops-cumulus-docs/topex/open/L2/docs/tpsafehold.txt
T/P Satellite Attitude Event Information
https://archive.podaac.earthdata.nasa.gov/podaac-ops-cumulus-docs/topex/open/L2/docs/tp_maneuver.txt
DIRECT S3-ACCESS
Available for access in-region with AWS Cloud
Region
us-west-2
Bucket/Object Prefix: Protected buckets contain the data files for a given collection. Protected simply means users must log in to Earthdata Login before gaining access to contents within that S3 Bucket. Please use the S3Credential endpoint to gain an Earthdata login token for use in S3 Access. Public buckets, in contrast, house metadata such as checksums, imagery, and metadata files and the like. A user can access public buckets and these types of files without logging in to Earthdata Login. Most of the time, you'll want to access the protected bucket Information
podaac-ops-cumulus-protected/TOPEX_POSEIDON_GDR_F/
podaac-ops-cumulus-public/TOPEX_POSEIDON_GDR_F/
AWS S3 Credentials
Get AWS S3 Credentials \| Documentation
TOOLS AND SERVICES
Data Subscriber

Name	Long Name	Unit
agc_20hz_c	20 Hz C-band corrected AGC	dB
agc_20hz_ku	20 Hz Ku-band corrected AGC	dB
agc_c	1 Hz C-band corrected AGC	dB
agc_ku	1 Hz Ku-band corrected AGC	dB
agc_numval_c	number of valid 20 Hz measurements used to compute 1 Hz C-band AGC	count
agc_numval_ku	number of valid 20 Hz measurements used to compute 1 Hz Ku-band AGC	count
agc_rms_c	RMS of C-band AGC	dB
agc_rms_ku	RMS of Ku-band AGC	dB
alt_echo_type	altimeter echo type
alt_state_flag_c_band	altimeter state flag: C-band bandwidth used
alt_state_flag_c_band_status	altimeter state flag: C-band status
alt_state_flag_ku_band_status	altimeter state flag: Ku-band status
alt_state_flag_oper	altimeter state flag: altimeter operating
altitude	1 Hz altitude of satellite	m
altitude_20hz	20 Hz altitude of satellite	m
altitude_cnes	1 Hz altitude of satellite	m
altitude_rate_mean_sea_surface	1 Hz orbit altitude rate	m/s
cg_to_altimeter_timevarying_offset	time varying CG correction to range	m
composite_wet_tropo_gpd	composite wet tropospheric correction	m
dac	dynamical atmospheric correction from ERA_Interim products	m
delta_ellipsoid_tp_wgs84	height difference between TOPEX and WGS84 reference ellipsoids	m
depth_or_elevation	ocean depth/land elevation	m
distance_to_coast	distance to shoreline	m
geoid	geoid height	m
ice_flag	ice flag
internal_tide_hret	coherent internal tide height (HRET)	m
inv_bar_cor	inverted barometer height correction from ERA_Interim products	m
iono_cor_alt_ku	Ku-band MLE4 ionospheric correction	m
iono_cor_alt_ku_mle3	Ku-band MLE3 ionospheric correction	m
iono_cor_gim_ku	GIM ionospheric correction on Ku band	m
l2_record_counter	Level 2 record counter	count
latitude	latitude	degrees_north
latitude_20hz	20 Hz latitude	degrees_north
load_tide_fes	load tide height for geocentric ocean tide (FES)	m
load_tide_got	load tide height for geocentric ocean tide (GOT)	m
longitude	longitude	degrees_east
longitude_20hz	20 Hz longitude	degrees_east
mean_dynamic_topography	mean dynamic topography above geoid	m
mean_dynamic_topography_acc	error on mean dynamic topography	m
mean_dynamic_topography_qual	mean dynamic topography interpolation flag
mean_sea_surface_cnescls	mean sea surface height above reference ellipsoid (CNES/CLS)	m
mean_sea_surface_cnescls_acc	calibrated error of mean sea surface (CNES/CLS)	m
mean_sea_surface_cnescls_qual	mean sea surface height interpolation flag (CNES/CLS)
mean_sea_surface_dtu	mean sea surface height above reference ellipsoid (DTU)	m
mean_sea_surface_dtu_acc	calibrated error of mean sea surface (DTU)	m
mean_sea_surface_dtu_qual	mean sea surface height interpolation flag (DTU)
mean_wave_period_t02	t02 mean wave period	s
meas_ind	elementary measurement index for Ku-band and C-band	count
model_dry_tropo_cor_measurement_altitude	model dry tropospheric correction at measurement altitude from ERA_Interim products	m
model_dry_tropo_cor_zero_altitude	model dry tropospheric correction at zero altitude from ERA_Interim products	m
model_wet_tropo_cor_zero_altitude	model wet tropospheric correction from ERA_Interim products	m
mqe_20hz_c	Mean Quadratic Error from 20 Hz C-band MLE3 numerical retracking	count
mqe_20hz_ku	Mean Quadratic Error from 20 Hz Ku-band MLE4 numerical retracking	count
mqe_20hz_ku_mle3	Mean Quadratic Error from 20 Hz Ku-band MLE3 numerical retracking	count
net_instr_cor_range_c	net instrumental correction on C-band MLE3 range	m
net_instr_cor_range_ku	net instrumental correction on Ku-band MLE4 range	m
net_instr_cor_range_ku_mle3	net instrumental correction on Ku-band MLE3 range	m
net_instr_cor_sig0_c	net instrumental correction on C-band MLE3 backscatter coefficient	dB
net_instr_cor_sig0_ku	net instrumental correction on Ku-band MLE4 backscatter coefficient	dB
net_instr_cor_sig0_ku_mle3	net instrumental correction on Ku-band MLE3 backscatter coefficient	dB
num_iterations_c	number of iterations for 20 Hz C-band MLE3 averaging	count
num_iterations_ku	number of iterations for 20 Hz Ku-band MLE4 averaging	count
num_iterations_ku_mle3	number of iterations for 20 Hz Ku-band MLE3 averaging	count
ocean_tide_eq	equilibrium long-period ocean tide height	m
ocean_tide_fes	geocentric ocean tide height (FES)	m
ocean_tide_fes_qual	ocean tide interpolation flag (FES)
ocean_tide_got	geocentric ocean tide height (GOT)	m
ocean_tide_got_qual	ocean tide interpolation flag (GOT)
ocean_tide_non_eq	non-equilibrium long-period ocean tide height	m
off_nadir_angle_wf_20hz_ku	20 Hz Ku-band MLE4 square of off nadir angle	degree^2
off_nadir_angle_wf_ku	1 Hz Ku-band MLE4 square of off nadir angle	degree^2
off_nadir_angle_wf_ku_qual	quality flag for 1 Hz Ku-band MLE4 square of off nadir angle
off_nadir_angle_wf_ku_smoothed	smoothed 1 Hz Ku-band MLE4 square of off nadir angle	degree^2
off_nadir_angle_wf_numval_ku	number of valid 20 Hz measurements used to compute 1 Hz Ku-band MLE4 square of off nadir angle	count
off_nadir_angle_wf_rms_ku	RMS of Ku-band MLE4 square of off nadir angle	degree^2
off_nadir_angle_wf_used_20hz_ku	flag indicating 20 Hz measurements used to compute 1 Hz Ku-band MLE4 square of off nadir angle
osc_drift_cor	oscillator drift correction to Ku- and C-band ranges	m
pole_tide	geocentric pole tide height	m
rad_atm_cor_sig0_c	two-way atmospheric attenuation on C band altimeter backscatter coefficient	dB
rad_atm_cor_sig0_c_qual	quality flag for radiometer two-way atmospheric correction to C band backscatter coefficient
rad_atm_cor_sig0_ku	two-way atmospheric attenuation on Ku band altimeter backscatter coefficient	dB
rad_atm_cor_sig0_ku_qual	quality flag for radiometer two-way atmospheric correction to Ku band backscatter coefficient
rad_cloud_liquid_water	radiometer cloud liquid water content	kg/m^2
rad_cloud_liquid_water_qual	quality flag for radiometer cloud liquid water content
rad_distance_to_land	radiometer main beam radial distance to land	m
rad_land_frac_18	land fraction within main beam of 18 GHz channel	1
rad_land_frac_21	land fraction within main beam of 21 GHz channel	1
rad_land_frac_37	land fraction within main beam of 37 GHz channel	1
rad_rain_flag	radiometer rain flag
rad_sea_ice_flag	radiometer sea ice flag
rad_surface_type_flag	radiometer surface type
rad_ta_18	radiometer antenna temperature at 18 GHz	K
rad_ta_18_qual	quality flag for 18 GHz antenna temperature
rad_ta_21	radiometer antenna temperature at 21 GHz	K
rad_ta_21_qual	quality flag for 21 GHz antenna temperature
rad_ta_37	radiometer antenna temperature at 37 GHz	K
rad_ta_37_qual	quality flag for 37 GHz antenna temperature
rad_tb_18	radiometer equalized brightness temperature at 18 GHz	K
rad_tb_18_qual	quality flag for 18 GHz equalized brightness temperature
rad_tb_21	radiometer equalized brightness temperature at 21 GHz	K
rad_tb_21_qual	quality flag for 21 GHz equalized brightness temperature
rad_tb_37	radiometer equalized brightness temperature at 37 GHz	K
rad_tb_37_qual	quality flag for 37 GHz equalized brightness temperature
rad_tmb_18	radiometer main beam brightness temperature at 18 GHz	K
rad_tmb_18_qual	quality flag for 18 GHz main beam brightness temperature
rad_tmb_21	radiometer main beam brightness temperature at 21 GHz	K
rad_tmb_21_qual	quality flag for 21 GHz main beam brightness temperature
rad_tmb_37	radiometer main beam brightness temperature at 37 GHz	K
rad_tmb_37_qual	quality flag for 37 GHz main beam brightness temperature
rad_water_vapor	radiometer water vapor content	kg/m^2
rad_water_vapor_qual	quality flag for radiometer water vapor content
rad_wet_tropo_cor	radiometer wet troposphere correction	m
rad_wet_tropo_cor_qual	quality flag for radiometer wet troposphere correction
rad_wind_speed	radiometer wind speed	m/s
rad_wind_speed_qual	quality flag for radiometer wind speed
rain_flag	rain flag
range_20hz_c	20 Hz C-band MLE3 range	m
range_20hz_ku	20 Hz Ku-band MLE4 range	m
range_20hz_ku_mle3	20 Hz Ku-band MLE3 range	m
range_c	1 Hz C-band MLE3 range	m
range_c_qual	quality flag for 1 Hz C-band MLE3 range
range_cor_doppler_c	doppler correction to C-band range	m
range_cor_doppler_ku	doppler correction to Ku-band range	m
range_ku	1 Hz Ku-band MLE4 range	m
range_ku_mle3	1 Hz Ku-band MLE3 range	m
range_ku_mle3_qual	quality flag for 1 Hz Ku-band MLE3 range
range_ku_qual	quality flag for 1 Hz Ku-band MLE4 range
range_numval_c	number of valid 20 Hz measurements used to compute C-band MLE3 range	count
range_numval_ku	number of valid 20 Hz measurements used to compute Ku-band MLE4 range	count
range_numval_ku_mle3	number of valid 20 Hz measurements used to compute Ku-band MLE3 range	count
range_rms_c	RMS of C-band MLE3 range	m
range_rms_ku	RMS of Ku-band MLE4 range	m
range_rms_ku_mle3	RMS of Ku-band MLE3 range	m
range_used_20hz_c	flag indicating 20 Hz measurements used to compute 1 Hz C-band MLE3 range
range_used_20hz_ku	flag indicating 20 Hz measurements used to compute 1 Hz Ku-band MLE4 range
range_used_20hz_ku_mle3	flag indicating 20 Hz measurements used to compute 1 Hz Ku-band MLE3 range
sea_state_bias_c	C-band MLE3 sea state bias correction	m
sea_state_bias_c_3d	sea state bias correction in C band computed from 3d model	m
sea_state_bias_ku	Ku-band MLE4 sea state bias correction	m
sea_state_bias_ku_3d	sea state bias correction in Ku band computed from 3d model	m
sea_state_bias_ku_mle3	Ku-band MLE3 sea state bias correction	m
sig0_20hz_c	20 Hz C-band MLE3 backscatter coefficient	dB
sig0_20hz_ku	20 Hz Ku-band MLE4 backscatter coefficient	dB
sig0_20hz_ku_mle3	20 Hz Ku-band MLE3 backscatter coefficient	dB
sig0_c	1 Hz C-band MLE3 backscatter coefficient	dB
sig0_c_qual	quality flag for 1 Hz C-band MLE3 backscatter coefficient
sig0_ku	1 Hz Ku-band MLE4 backscatter coefficient	dB
sig0_ku_mle3	1 Hz Ku-band MLE3 backscatter coefficient	dB
sig0_ku_mle3_qual	quality flag for 1 Hz Ku-band MLE3 backscatter coefficient
sig0_ku_qual	quality flag for 1 Hz Ku-band MLE4 backscatter coefficient
sig0_numval_c	number of valid 20 Hz measurements used to compute C-band MLE3 backscatter coefficient	count
sig0_numval_ku	number of valid 20 Hz measurements used to compute Ku-band MLE4 backscatter coefficient	count
sig0_numval_ku_mle3	number of valid 20 Hz measurements used to compute Ku-band MLE3 backscatter coefficient	count
sig0_rms_c	RMS of C-band MLE3 backscatter coefficient	dB
sig0_rms_ku	RMS of Ku-band MLE4 backscatter coefficient	dB
sig0_rms_ku_mle3	RMS of Ku-band MLE3 backscatter coefficient	dB
sig0_used_20hz_c	flag indicating 20 Hz measurements used to compute 1 Hz C-band MLE3 backscatter coefficient
sig0_used_20hz_ku	flag indicating 20 Hz measurements used to compute 1 Hz Ku-band MLE4 backscatter coefficient
sig0_used_20hz_ku_mle3	flag indicating 20 Hz measurements used to compute 1 Hz Ku-band MLE3 backscatter coefficient
solid_earth_tide	solid earth tide height	m
ssha	sea surface height anomaly	m
ssha_mle3	sea surface height anomaly	m
surface_classification_flag	surface_classification_flag
swh_20hz_c	20 Hz C-band MLE3 significant waveheight	m
swh_20hz_ku	20 Hz Ku-band MLE4 significant waveheight	m
swh_20hz_ku_mle3	20 Hz Ku-band MLE3 significant waveheight	m
swh_c	1 Hz C-band MLE3 significant waveheight	m
swh_c_qual	quality flag for 1 Hz C-band MLE3 significant waveheight
swh_ku	1 Hz Ku-band MLE4 significant waveheight	m
swh_ku_mle3	1 Hz Ku-band MLE3 significant waveheight	m
swh_ku_mle3_qual	quality flag for 1 Hz Ku-band MLE3 significant waveheight
swh_ku_qual	quality flag for 1 Hz Ku-band MLE4 significant waveheight
swh_model	significant waveheight from model	m
swh_numval_c	number of valid 20 Hz measurements used to compute C-band MLE3 significant waveheight	count
swh_numval_ku	number of valid 20 Hz measurements used to compute Ku-band MLE4 significant waveheight	count
swh_numval_ku_mle3	number of valid 20 Hz measurements used to compute Ku-band MLE3 significant waveheight	count
swh_rms_c	RMS of C-band MLE3 significant waveheight	m
swh_rms_ku	RMS of Ku-band MLE4 significant waveheight	m
swh_rms_ku_mle3	RMS of Ku-band MLE3 significant waveheight	m
swh_used_20hz_c	flag indicating 20 Hz measurements used to compute 1 Hz C-band MLE3 significant waveheight
swh_used_20hz_ku	flag indicating 20 Hz measurements used to compute 1 Hz Ku-band MLE4 significant waveheight
swh_used_20hz_ku_mle3	flag indicating 20 Hz measurements used to compute 1 Hz Ku-band MLE3 significant waveheight
time	time in UTC (sec. since 2000-01-01)	seconds since 2000-01-01 00:00:00.0
time_20hz	time 20 Hz in UTC (sec. since 2000-01-01)	seconds since 2000-01-01 00:00:00.0
time_tai	time in TAI	seconds since 2000-01-01 00:00:00.0
wind_speed_alt	Ku-band MLE4 wind speed	m/s
wind_speed_alt_mle3	Ku-band MLE3 wind speed	m/s
wind_speed_mod_u	U component of the model wind vector from ERA_Interim products	m/s
wind_speed_mod_v	V component of the model wind vector from ERA_Interim products	m/s

DATA CITATION POLICY
https://podaac.jpl.nasa.gov/CitingPODAAC Data Use and Citation Policy
USER'S GUIDE
https://archive.podaac.earthdata.nasa.gov/podaac-ops-cumulus-docs/topex/open/L2/docs/D-73899_tpx-grdf-hdbk-20230626_w-sigs.pdf TOPEX/POSEIDON GDR-F Products Handbook
GENERAL DOCUMENTATION
https://www.jpl.nasa.gov/missions/topex-poseidon TOPEX/Poseidon Mission Page at JPL
https://sealevel.jpl.nasa.gov/missions/topex-poseidon/ TOPEX/Poseidon Mission Page at NASA Sea Level

Citation is critically important for dataset documentation and discovery. Please cite the data as follows, and cite the reference papers when it is appropriate.

Citation

TOPEX/Poseidon. 2023. TOPEX/Poseidon Geophysical Data Record Version F. Ver. F. PO.DAAC, CA, USA. Dataset accessed [YYYY-MM-DD] at https://doi.org/10.5067/TPXPS-GDRF1

Download Citation
RIS	BIB	XML	JSON-LD

For more information see Data Citations and Acknowledgments.

Journal Reference

Fu, L.-L., Christensen, E. J., Yamarone, C. A., Lefebvre, M., Ménard, Y., Dorrer, M., and Escudier, P.. 1994. TOPEX/POSEIDON mission overview, J. Geophys. Res., 99, C12. https://doi.org//10.1029/94JC01761

Cloud Enabled

Status:

COMPLETE

Short Name:

TOPEX_POSEIDON_GDR_F

Collection Concept ID:

C2599212091-POCLOUD

Spatial Coverage:

N: 66°

S: -66°

E: 180°

W: -180°

Access:

Capabilities:

Tools

PO.DAAC Data Subscriber

Information


                        Simple: podaac-data-downloader -c TOPEX_POSEIDON_GDR_F -d ./data --start-date 1992-10-13T00:00:00Z --end-date 1992-10-20T00:00:00Z -e ""
Download by Spatial and Temporal Search: podaac-data-downloader -c TOPEX_POSEIDON_GDR_F -d ./data --start-date 1992-10-13T00:00:00Z --end-date 1992-10-20T00:00:00Z -b="-180,-66,180,66"
Download by Extension: podaac-data-downloader -c TOPEX_POSEIDON_GDR_F -d ./data --start-date 1992-10-13T00:00:00Z --end-date 1992-10-20T00:00:00Z -e .nc
Download by Cycle: podaac-data-downloader -c TOPEX_POSEIDON_GDR_F -d ./data --cycle 3
Download recent data (360 min.): podaac-data-subscriber -c TOPEX_POSEIDON_GDR_F -d ./data -m 360
Download recent data (1440 min.): podaac-data-subscriber -c TOPEX_POSEIDON_GDR_F -d ./data -m 1440

Services

PO.DAAC harmony-netcdf-to-zarr

Information


                        https://harmony.earthdata.nasa.gov/C2599212091-POCLOUD/ogc-api-coverages/1.0.0/collections/all/coverage/rangeset?format=application%2Fx-zarr

Direct S3-Access

Available for access in-region with AWS Cloud

Region:

us-west-2

Bucket/Object Prefix Protected buckets contain the data files for a given collection. Protected simply means users must log in to Earthdata Login before gaining access to contents within that S3 Bucket. Please use the S3Credential endpoint to gain an Earthdata login token for use in S3 Access.

Public buckets, in contrast, house metadata such as checksums, imagery, and metadata files and the like. A user can access public buckets and these types of files without logging in to Earthdata Login.

Most of the time, you'll want to access the protected bucket Information

podaac-ops-cumulus-protected/TOPEX_POSEIDON_GDR_F/

podaac-ops-cumulus-public/TOPEX_POSEIDON_GDR_F/

AWS S3 Credentials

Get AWS S3 Credentials | Documentation

PO.DAAC

Navigation

You are here

TOPEX/POSEIDON Geophysical Data Record Version F

TOPEX/POSEIDON Geophysical Data Record Version F

Navigation

You are here

TOPEX/POSEIDON Geophysical Data Record Version F

TOPEX/POSEIDON Geophysical Data Record Version F

Share Dataset URL

Tools

Services

Direct S3-Access

Services

Services