Since the waypoint change last week, Challengers slowed down quite a bit as the currents have now shifted to the North, despite both models consistently showing more of a westward flux.
Looking ahead, as we continue to maintain our position between the orange line (direct route from Ubatuba to Cape Town) and the red line (angled path bringing 29 towards Tristan da Cunha ) there is an interesting system lying a few hundred kilometers to our east.
The Depth Average currents for RTOFS August 14
In the RTOFS forecast above, there appears to be a large cold core eddy spinning in the clockwise direction, while below in the copernicus forecast, there are two warm core eddies rotating in the counter-clockwise direction; both resulting in a westward flux. As both models use similar baseline readings to then derive their forecasts from, it is very interesting to see the two different reasonings behind the same westward current, and so over the next few weeks as 29 makes her way in that direction, we will keep an eye out on the data to see the evidence in our data for which forecast will get this right.
The Depth Average Current forecast for the Copernicus Model August 14
In the meantime as we make our way towards this test area, Challenger has to snake her way through the seamounts immediately ahead of us. With the current to the north of the seamounts being due west, we have decided to duck down to the south through the valley before cutting back to the east where the current look to be more favorable.
Global Bathymetry Product for the South Atlantic Region
Force Wind Sea & Honor