Hey All!
So we are now preparing once again to get Silbo back in the water and on his way home. It has been 66 days since the emergency operation that involved recovering Silbo under cover of darkness after a sever drop in voltage, but now we have a team soon departing for the Azores to get him back on his feet.
For this next leg of the mission, running from the Azores to the Canaries (just over 1,300 km), Silbo will be modified as a stretch glider with Alkaline battery packs. A stretch glider has two battery bays to allow the glider to hold more batteries and spend more time at sea. Ru 27, the glider that flew successfully across the Atlantic from NJ to Spain back in 2009 had a similar set up.
For now, the plan is that the new battery bay and battery packs will be sent out this week and a team from Teledyne Webb will soon follow. The deployment should take place towards the end of the month.
The remaining ~1300km should take Silbo from the end of February until about Mid May where he will be received with a warm welcome at his home in the Canary Islands.
Looking at the Bathymetry plot above, we should not have too many obstacles on the trip from the Azores to the Canaries. The coloration is all the deep blue (everywhere except where the islands rise from the sea floor) is 1000+ m depth. Silbo’s max depth he can handle is about 1000m, so far averaging about 980m per dive, so we should not have to worry about using too much battery on the altimeter.
We also have a newly updated tool that will definitely prove its helpfulness. Last week, Antonio introduced us to a new product that he made over at ULPGC. It is a set of movies to be viewed in google earth that shows the progression of salinity and currents over the month of January.
With this updating, we will be able to see what the ocean has been doing to try and make the best estimation of what it will do in the near future. But soon, we won’t even have to make predictions. As we near the range of Spain’s ROM data, we will have the potential to make accurate predictions at up to +96 hrs. This will definitely prove to be helpful in piloting Silbo.
Antonio and his team has also made an incredible discovery from this new feature: Mediterranean eddies forming between 600-1200m.
These Mediterranean Eddies are a product of the super salty water of the Mediterranean Sea spilling out into the North Atlantic where it sinks due to the difference in density. These solar system groups of eddies are causing currents up to .2m/s at depth which we can use to aid in helping Silbo along. Keeping an eye on these ‘meddies’ will be key in piloting and will give us some amazing data.
In the time Silbo has been out of the water, we have also begun to analyze the data collected thus far. One plot originally created by our friends Ruben Marrero and Alberto Gonzalez from PLOCAN shows the first visualization of Heat Transport from the data collected by a Slocum Glider.
This plot starting at the point nearest the viewer shows data from Iceland to the far edge of the plot where Silbo is about even with Ireland. In relation to the viewer, up and down measures the heat transport of the North Atlantic in relation to the glider measured in Jouls * meters/second. The data set used to create this plot however is incomplete and hopefully soon I will be able to produce a plot with data covering the nearly 4000km from deployment to recovery in December 2011.
I also led a group of students ( Jess Castoro, Chris Puskas, Eva Pena, Holly Broadus) last semester as we looked at the temperature and salinity data recorded from Silbo and compared to data collected from the Argos drifters scattered throughout the world’s ocean. Our goal was to see if the change in conditions (temperature & salinity) that we saw on the journey from the arctic waters off of Iceland to the more temperate waters of the Azores were due regional or temporal differences. (click on the two images below to see the temperature and salinity data respectively)
What we concluded after looking at the different plots we created was that the temperature change off of Iceland was minimal while the change near Silbo’s position on October 3rd was much larger. This lead to the conclusion that the temperature difference seen between the end of June and beginning of October was both regional and temporal. On the other hand, we believe the differences seen in the salinity could be due to high fresh water flux in Iceland compared to influences of the Mediterranean on our position in October.
Finally, last week Ralph Rayner, Chair of the Oceanology International meeting in London visited the COOL room where we was given a tour of our top of the line facility and discussed the Challenger Mission with Scott
That is all for now. Check back over the next couple weeks as we finalize the preparations of Silbo as we send him back on his way home!
Force Wind Sea & Honor!
Nilsen & Antonio