Hey All,
So there has been quite a lot of activity over the past couple days as we made a few crucial decisions for piloting Silbo.
First off, we have made a few way point changes ranging from east to south east as we are making our way through the eddy solar system we have been flying for the past few weeks. We have also changed our flight parameters to flying at 300cc instead of 400. This is to save power as we are no longer fighting strong head currents (which was the causation towards the beginning of the mission to make the decision to move it up to 400cc). Also in an attempt to save battery, we are continuing to only turn on the ctd for 1 down cast for every two yo dive while doing one dive every two weeks to validate the data collected.
Temperature recorded by Silbo on March 28
Salinity recorded by Silbo on March 28
Density derived by Silbo's data from March 28
As seen in the three figures above, the down cast (blue) and up cast (red) and relatively along the same trend showing that the ctd sensor is still functioning well.
Taking these measures to conserve energy is also proving to be working very well. Below there are a couple figures showing energy consumption, estimated end date for the life of the batteries, and estimated distance that can be covered off of how much energy we have left.
Top: Amps/hr consumed so far Bottom: Estimated end date
Flight Estimation Plots for Silbo
Based on the above plots, Silbo should have enough battery to last until mid June and can cover about 2,500km, well over the ~750 km track that Silbo will follow to get to the Canary Islands via sailing by the island of Madeira. The remainder of the trip is estimated to be about another month and half, Madeira being about 3 weeks away. Leaving Funchal’s harbor, Carlos and a team from PLOCAN plan on running an inspection to make sure there is nothing growing on the exterior of Silbo and will simultaneously deploy drifters in the water. This will all happen about 50 km west of the island.
In order to most strategically fly silbo to 50 km from madeira, it would be necessary to keep flying east for a while to make sure we can reach the rendezvous point without having to try and fly back to the north against the southern flow that goes from Madeira to the Canaries. But once we get past the inspection, it should be relatively smooth sailing as we ride the tail end of the Canary current to our final destination.
To get better estimations of the time for the remainder of the mission, Daniel Hernández, Josep Isern, Enrique Fernández and the rest of the team from ROC-SIANI group at ULPGC used their simulation to see how long it will take Silbo to get to the Canaries.
Pinzon path planning estimation using myocean
Pinzon path planning simulation using hycom
Currents comparison recorded by Silbo (g) hycom (b) myocean (m)
These estimations show we should be in the vicinity of Madeira within the next two weeks or so. However we may need to delay a bit as we need a little more time for our team to arrive. However it seems Silbo has plenty of battery power to bide a little time.
Based off of speeds Silbo has reached thus far on the mission, if Silbo maintains a speed of .35 m/s, we are looking at an arrival at Madeira by april 9-13, .3m/s would give us a date of april 11-15, or .25 m/s would land us at april 13-17.
To make sure we find the most ideal path, we have been keeping a keen eye on our various ocean models, both on the surface and at depth.
myocean surface conditions for temperature, salinity, currents and sea surface height
myocean temperatures at depth
myocean salinity at depth
myocean currents at depth
ncom currents and nlom sea surface height
hycom density and currents
hycom salinity
hycom sea surface height
hycom temperature
The ocean models shown above (myocean, ncom/nlom, hycom) all show the general trend in the currents we have seen agreeing with the currents recorded by silbo. As for now we will continue to follow the way point as we continue to make progress to the east.
Finally, I would just like to point out some beautiful imagery from the modis satellite imagery of the north atlantic of temperature and chlorophyll (where I got the title from).
modis sea surface temperature
modis chlorophyll imagery
check back soon for more updates on Silbo’s journey!
as always, Force, Wind, Sea & Honor
Nilsen Strandskov, Antonio Ramos, Ben Allsup, Lauren Cooney & Oliver Ho