Abstract's details
Satellite Altimetry Sea Surface Height Anomaly Processing At The Naval Oceanographic Office’s Altimetry Data Fusion Center
Event: 2015 Ocean Surface Topography Science Team Meeting
Session: Application development for Operations (previously NRT splinter)
Presentation type: Type Poster
Contribution: PDF file
Abstract:
The Altimetry Data Fusion Center (ADFC) at the Naval Oceanographic Office processes, evaluates, produces, and disseminates near real-time altimetry-derived Sea Surface Height Anomaly (SSHa) products for assimilation into operational oceanographic models. The ADFC produces and distributes timely, accurate, and quality-controlled altimetry SSHa observations to agencies in the Department of Defense, the National Centers for Environmental Prediction, the National Aeronautics and Space Administration, and other civilian agencies. Current SSHa products provided by the ADFC utilize altimetry satellite data from the Jason-2, SARAL/AltiKa, and Cryosat-2 missions.
The ADFC produces ~ 50,000 SSHa observations per satellite per day. SSHa data latency is 24 to 48 hours from the satellite observation time. SSHa data are calculated by differencing along-track SSH observations (time and position) to a long term along-track reference mean. SSHa data are assimilated into ocean models that provide ocean circulation and acoustic predictions. SSHa observations measure the thickness of the ocean column, which varies with ocean mesoscale features, and are also the primary input into the upper ocean heat content analysis for the hurricane intensity models. These models are used to predict ocean energy potential for tropical storms.
Satellite data outputs are verified and compared with the other operational satellite outputs for the fraction/percent data used, orbit correction applied, and crossover RMS difference comparisons. Also, the ADFC is currently conducting a study, to be operationalized in the future, for satellite SSHa comparisons with in situ temperature-salinity profiles. This study compares satellite altimeter SSHa to steric height anomaly calculated from quality controlled temperature-salinity profiles. The two data sets are matched using a range of time and distance constraints, and the differences are examined. These comparisons can be used to identify future discrepancies or anomalies found in either data source. Ultimately these results can assist to identify sensor measurement constraints and improve satellite inputs to ocean forecast models.
The ADFC produces ~ 50,000 SSHa observations per satellite per day. SSHa data latency is 24 to 48 hours from the satellite observation time. SSHa data are calculated by differencing along-track SSH observations (time and position) to a long term along-track reference mean. SSHa data are assimilated into ocean models that provide ocean circulation and acoustic predictions. SSHa observations measure the thickness of the ocean column, which varies with ocean mesoscale features, and are also the primary input into the upper ocean heat content analysis for the hurricane intensity models. These models are used to predict ocean energy potential for tropical storms.
Satellite data outputs are verified and compared with the other operational satellite outputs for the fraction/percent data used, orbit correction applied, and crossover RMS difference comparisons. Also, the ADFC is currently conducting a study, to be operationalized in the future, for satellite SSHa comparisons with in situ temperature-salinity profiles. This study compares satellite altimeter SSHa to steric height anomaly calculated from quality controlled temperature-salinity profiles. The two data sets are matched using a range of time and distance constraints, and the differences are examined. These comparisons can be used to identify future discrepancies or anomalies found in either data source. Ultimately these results can assist to identify sensor measurement constraints and improve satellite inputs to ocean forecast models.