We have long suggested that the satellite based measurements of ocean currents called OSCAR (Ocean Surface Current Analyses Real-time) are often the best guide for optimum sailboat routing.
The present form of the data (0.25ยบ resolution; avg depth 15m, 24-hr averages, run daily, but with a 5-day latency) are available since 2020, but the raw data are in NetCDF format, which is not compatible with most navigation applications (electronic charting systems, ECS).
Recently we have outlined how to get archived yacht race routes into various ECS along with how to get the historic winds and waves in GRIB format (reanalyzed ECMWF) for the same time of the race.
Now we want to show how you can also get the historic OSCAR currents for these past races, so when you practice with your own routing to compare with the historic tracks you have all the data needed.
For direct access to the OSCAR data, you will need to set up a free account at the NASA Earth Data site. This takes just seconds and is totally non-invasive, plus offers other features as well.
Step 1. Get a subsetted copy of the data in NetCFD format from this link:
Step 2. Convert that file to GRIB format with this link:
Notes:
(1) If no one has used our conversion service recently, then it will have gone to sleep, and we have to wait about a minute for it to wake up, and then it will complete the task. The next conversion will happen quickly. This is a fair price we pay for using the free mode of a powerful app server. In the wait we learn about what they offer.
(2) You can also get the latest OSCAR currents this way, but that is more convenient from LuckGrib or SVSarana, as discussed at starpath.com/currents. The latest data will always be five days old, regardless of where you get it, but doing it this way, you would have to enter a date five days ago.
(3) Here is an 8-min video example.
Let us know if you have any questions about this at helpdesk@starpath.com
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