SSALTO/DUACS Multimission Altimeter Products

Merged-Gridded Sea Level Anomalies and Absolute Dynamic Topography heights and currents in near real-time

Near-Real Time (SEALEVEL_GLO_PHY_L4_NRT_OBSERVATIONS_008_046):

Altimeter satellite gridded Sea Level Anomalies (SLA) computed with respect to a twenty-year 2012 mean. The SLA is estimated by Optimal Interpolation, merging the measurement from the different altimeter missions available (see QUID document or http://duacs.cls.fr [1] pages for processing details). The product gives additional variables (i.e. Absolute Dynamic Topography and geostrophic currents (absolute and anomalies)).This product is processed by the DUACS multimission altimeter data processing system. It serves in near-real time the main operational oceanography and climate forecasting centers in Europe and worldwide. It processes data from all altimeter missions: Jason-3, Sentinel-3A, HY-2A, Saral/AltiKa, Cryosat-2, Jason-2, Jason-1, T/P, ENVISAT, GFO, ERS1/2. It provides a consistent and homogeneous catalogue of products for varied applications, both for near real time applications and offline studies. To produce maps of Sea Level Anomalies (SLA) and Absolute Dynamic Topography (ADT) in near-real-time, the system uses the along-track altimeter missions from products called SEALEVEL*_PHY_L3_NRT_OBSERVATIONS_008_*. Finally an Optimal Interpolation is made merging all the flying satellites in order to compute gridded SLA and ADT. The geostrophic currents are derived from sla (geostrophic velocities anomalies, ugosa and vgosa variables) and from adt (absolute geostrophic velicities, ugos and vgos variables).

This product is processed by the SL-TAC multimission altimeter data processing system. It serves in near-real time the main operational oceanography and climate forecasting centers in Europe and worldwide. It processes data from all altimeter missions: Jason-3, Sentinel-3A, HY-2A, Saral/AltiKa, Cryosat-2, Jason-2, Jason-1, T/P, ENVISAT, GFO, ERS1/2. It provides a consistent and homogeneous catalogue of products for varied applications, both for near real time applications and offline studies.

Variables
sea level anomaly (m)
formal mapping error (m)
geostrophic velocity anomalies: zonal component (m/s)
geostrophic velocity anomalies: meridional component (m/s)
absolute dynamic topography (m)
absolute geostrophic velocity: zonal component (m/s)
absolute geostrophic velocity: meridional component (m/s)
absolute geostrophic velocity error: zonal component (m/s)
absolute geostrophic velocity error: meridional component (m/s)
ZonalGlobal by 1/4 deg
MeridionalGlobal by 1/4 deg
VerticalN/A  
Temporal Dec 1, 2019 to Nov 25, 2024 by 1 day
Static?no
Volume 7.5MB per day
Serverprivate:
SourceDelayed-Time (SEALEVEL_GLO_PHY_L4_REP_OBSERVATIONS_008_047)
Near-Real Time (SEALEVEL_GLO_PHY_L4_NRT_OBSERVATIONS_008_046)
Acquired March 14, 2022
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