Through the winter holiday, Challenger continued to make good progress while not only breaking speed records for the mission, but crossed back over to the Eastern hemisphere for the first time since early 2013.
As Challenger continued her approach to the Prime Meridian, we saw a nice correlation between the currents across the board as the depth average currents from the glider matched the eddy in both copernicus and RTOFS.
While making her way across the southern edge of the eddy, Challenger broke her mission speed record, breaking 37 km/day.
Then as 29 finally crossed the Prime Meridian, the glider began to feel the push of the eastern side of the warm core eddy. In order to avoid the seamount to the east, we let the glider follow the flow of the eddy and rode it to the north. The seamounts although labeled as only reaching to 750m from the surface while Challenger is diving to 550m, the depths are not always accurate and so we like to keep a level of caution when flying by one. The altimeter was also turned on as a secondary temporary precaution.
So now the challenge is the biofouling. We are not flying as deep to help save the pump and reduce the power draw, but we see the slow deterioration in steering and vertical velocity. So we are still in a race. We have to get to Cape Town before the biofouling slows our progress to the point where we loose our steering.
Now just 1750 km from where she was deployed in Jan 2013, we are looking ahead at the stream of eddies we will navigate in the coming months as we get Challenger back to South Africa and complete the flights for the South Atlantic.
Force Wind Sea & Honor