ATLAS/ICESat-2 L3A Ocean Surface Height, Version 7
Data set id:
ATL12
DOI: 10.5067/ATLAS/ATL12.007
This is the most recent version of these data.
Version Summary
Version Summary
-Significantly improved ocean surface height in ice-covered water by using aligned ATL07 sea ice reference surface data (leads) if ATL12-estimated heights are considered contaminated by ice
-Added ice-free height estimates based on aligned ATL07 sea ice product reference surface data (leads) at both the ocean segment rate and 10-meter rate
-Added 10-meter rate standard deviation of htybin (htybin_std_seg).
-Added the along-track distance from the equator crossing to the first 10 m bin for each ocean segment (xbind_first_dist_x). This allows accurate alignment for ATL13 short segments with other ICESat-2 data products.
-Added the first photon bias correction for each 10 m along-track bin in each ocean segment (fpb_10m)
-Added the estimated error in first photon bias correction (fpb_corr_stdev)
-Added computation of the sea slope bias estimated from the correlation of photon return rate with along-track 10-meter bin averaged surface height (bin_slopebias)
-Added computation of the sea slope magnitude bias estimated from the covariance of the photon rate and the slope (bin_magslopebias)
-Excluded photons without a valid tide_ocean from ocean segment processing
-Added selective use of ocean scan calibration data to be included or excluded from being processed
-Added usage of ATL03 photon quality into ocean photons selection to remove fully saturated pulses
-Changed the source for bathymetry to the 2022 GEBCO bathymetry grid
-Changed the source for ice concentration (ice_conc) to the high-resolution AMSR2 passive microwave SIC dataset
-Added ice-free height estimates based on aligned ATL07 sea ice product reference surface data (leads) at both the ocean segment rate and 10-meter rate
-Added 10-meter rate standard deviation of htybin (htybin_std_seg).
-Added the along-track distance from the equator crossing to the first 10 m bin for each ocean segment (xbind_first_dist_x). This allows accurate alignment for ATL13 short segments with other ICESat-2 data products.
-Added the first photon bias correction for each 10 m along-track bin in each ocean segment (fpb_10m)
-Added the estimated error in first photon bias correction (fpb_corr_stdev)
-Added computation of the sea slope bias estimated from the correlation of photon return rate with along-track 10-meter bin averaged surface height (bin_slopebias)
-Added computation of the sea slope magnitude bias estimated from the covariance of the photon rate and the slope (bin_magslopebias)
-Excluded photons without a valid tide_ocean from ocean segment processing
-Added selective use of ocean scan calibration data to be included or excluded from being processed
-Added usage of ATL03 photon quality into ocean photons selection to remove fully saturated pulses
-Changed the source for bathymetry to the 2022 GEBCO bathymetry grid
-Changed the source for ice concentration (ice_conc) to the high-resolution AMSR2 passive microwave SIC dataset
Overview
ATL12 contains along-track sea surface height (SSH) of the global open ocean relative to the WGS84 ellipsoid. Height averages, distributions, and uncertainties are provided over ocean segments 400 to 7,000 m in length. Heights relative to the EGM2008 geoid and variables such as photon return rate are provided in 10 m along-track bins within each ocean segment. Additionally, 10 m bins corresponding to ATL07 bright leads are identified, and heights within the bins are averaged over ocean segments to yield accurate SSHs where ice concentrations are greater than 15%. The data were acquired by the Advanced Topographic Laser Altimeter System (ATLAS) instrument on board the ICESat-2 observatory.
Parameter(s):
SEA SURFACE HEIGHT
Platform(s):
ICESat-2
Sensor(s):
ATLAS
Data Format(s):
HDF5
Temporal Coverage:
- 13 October 2018 to present
Temporal Resolution:
- 91 day
Spatial Resolution:
- Not Specified
Spatial Reference System(s):
- WGS 84EPSG:4326
Spatial Coverage:
- N:88S:-88E:180W:-180
Blue outlined yellow areas on the map below indicate the spatial coverage for this data set.
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