Ocean Surface Current Analyses Real-time (OSCAR) is a NASA funded research project and global surface current database. The OSCAR ocean surface mixed layer velocities are calculated from satellite-sensed sea surface height gradients, ocean vector winds, and sea surface temperature fields using geostrophy, Ekman, and thermal wind dynamics.
OSCAR’s continuing improvement depends on better modeling of the momentum transfer both within and across the boundaries of the turbulent mixed layer. A main research objective of the OSCAR project is to improve the generation of surface currents by ocean vector winds, and in doing so further our understanding of the mechanisms behind the transfer of momentum between the atmosphere and the ocean through the planetary boundary layer.
We released OSCAR version 2.0 through the NASA JPL Physical Oceanography data center, PO.DAAC, in January 2022 (https://podaac.jpl.nasa.gov/dataset/OSCAR_L4_OC_INTERIM_V2.0, Dataset “Ocean Circulation”). In this v2.0, OSCAR is provided as daily files in NetCDF format that contain total zonal (u) and meridional (v) velocities as well as the zonal (ug) and meridional geostrophic (vg) components.
The data is available in three quality levels: final, interim, and near-real-time (nrt). The quality levels are determined by the best available source datasets and are intended to provide users with the best quality data while still producing near-real-time data.
The manuals on the PO.DAAC dataset pages provide more detailed information about OSCAR, such as the data format, coverage, how to cite, etc. Answers to many questions about the PO.DAAC in general, the user registration system, how to retrieve data, specific questions about datasets themselves, and user shared scripts can both be found and posted on the PO.DAAC forum.
This new version is stored in the cloud. Information about access to PO.DAAC datasets in the cloud can be found here: https://podaac.jpl.nasa.gov/cloud-datasets/about.
The previous versions of OSCAR will only be available for a few months of overlap with version 2.0. In the previous versions, surface currents are provided on a regular global grid every ~5 days, dating from 1992 to present day, with daily updates and near-real-time availability. OSCAR currents are on either 1 degree and 1/3 degree grid spacing in NetCDF format. Sample plots of Gulf Stream rings comparing the new v2.0 to the OSCAR 1/3 degree are shown below.