So Silbo is still barreling on his way towards Madeira as the currents continue to unfortunately be favorable. With the way the currents have been moving, it seems we may need to take some sort of evasive maneuver to prevent ourselves from getting too close to the island where we will find unpleasant bathymetry and some pretty heavy ship traffic. The most likely scenario would be to station keep for a while (fly between two close waypoints) until the team with the drifter can get out there to inspect silbo and deploy the drifter.
In the image above of density along with the images below from the hycom model, we can see that Silbo continues to ride down hill along the mesoscale as he heads towards his waypoint. According to the models, it looks like if we were to go north a bit and fly with our nose into the cold eddy, we could slow ourselves down. This could solve our problem of hitting speeds up to .45m/s
Now looking at the myocean data to see what is going on throughout the water column, the salinity really portrays the best idea of what Silbo is dealing with subsurface.
It seems that deep salted cold fluxes of Mediterranean water have increased flow into the atlantic over the past couple months.
During the winter, the convective cell NW mediterranean is really intense (transmitting heat to the french, spaniard, italian coasts thus preventing its freezing. This cold salted water sunk and streamed along the eastern coast of spain, flowing south and then left the mediterranean through the straight of gibraltar and sank down to 600 m. The effects of the out reach of this salted mediterranean layer can be seen in the images showing salinity at 600, 800 and 1000m.
If you look at the salinity for the upper ocean, it is pretty uniform from the surface to 400m. However if you go deeper, Med water appears around silbo at 600 m, and have an affect until his deepest diving depth 1000 m.
Looking ahead, there are some salt driven eddies around him coming from the NE. This most likely is the explanation of how different the current fields are between the surface-500m and 500m-1000m.
But the Mediterranean will not continue to be a huge driving factor much longer. There is some cold but fresher water reaching up from the south that keeps the mediterranean waters north of Madeira
Force Wind Sea and Honor
Nilsen Strandskov, Antonio Ramos, & Oliver Ho