Category: silbo (Page 13 of 22)

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

Hey All!

As we all get ready to say goodbye to the weekend and start up the new week, Silbo is gearing up to hurtle over a wall!

HyCOM Sea Surface Height and Currents map

Silbo is coming around the south east side of the cold sun eddy over the next day where he will then encounter what looks to be one of the strongest currents we have seen since redeployment.  Unfortunately it is flowing north and so Silbo is going to have to fight his way across (hopefully without being pushed too far off course) as we continue on our way to the south east towards Madeira and ultimately the Canary Islands.  This afternoon silbo was given a new way point south east of his most recent location to try and fly at an angle to the currents to evade any negative progress.

Nilsen & Antonio

Hey All!

Just a quick update as we head into the weekend:

This afternoon we gave Silbo a new way point to the south as we try and cut across the strong east northeast current that we are in.

HYCOM Sea Surface Height

Over the past couple days we started being drawn in towards the core of the blue cold eddy as we encountered stronger currents.  In an attempt to avoid being pulled up and back to the north, we are working on cutting back south across the strong east current of the bottom of the cold core eddy.  If we succeed, we will be within two weeks of a rendezvous just west of Madeira and we may reach the Canaries in about 5 -6 weeks.

Also this week, we ran one dive where we had the ctd on for two consecutive up and down casts so we can keep an eye on it and make sure the data is accurate as possible.  Down casts are in blue while up casts are red.

Temperature profile from surface to ~1000m collected by Silbo

Sea Water Salinity from surface to 1000m collected by Silbo

Seeing that the 4 lines are relatively close and do not show any major lags indicates the ctd is functioning correctly.  Also looking at the salinity, we can see the effects of the ‘meddies’ or salty water from the Mediterranean starting at about 700m depth.

Finally I just want to leave everyone with the big picture of the obstacles that lie ahead.  Aside from working our way through the eddies that lie between Silbo and the sunny shores of the Canaries, there are also a number of heavily trafficked areas when we start getting closer to land.  It will be crucial to keep an eye on such resources such as localizada and marine traffic’s ais data to make sure Silbo is not struck by any ships

Force Wind Sea & Honor

Nilsen & Antonio

Hey All,

So just a quick recap of the past week: Silbo has flying pretty well averaging just around 7.5 km per 7 hr stint as he made his way through the currents created by the eddy solar system.  However, over the past day and a half, there has been a significant change in scenery… The massive cold core sun has collapsed into a couple much smaller counter clockwise spinning eddies.  With this collapse, there have been a number of other changes in the regions ahead that will make the piloting a little more tricky as we try and maintain the plan we had previously of getting to Madeira.  Our main obstacle is the strong north current that is on the other side of the remnants of the sun we are working our way around.

Although we know there chances of this path staying put are pretty slim, we still hope this general flow will hold over the next month as we fly our way east towards Madeira.  Giving us a slight glimpse of optimism is that our HYCOM and MYOCEAN models are complimenting each other quite nicely: all showing that both surface and sub surface conditions are for the moment in our favor.

HYCOM Density & Currents Map

HYCOM Salinity & Currents Map

HYCOM Sea Surface Height & Currents Map

HYCOM Temperature & Currents Map

MYOCEAN Sea Surface Height Map

MYOCEAN Surface Conditions (Currents, East Component of Currents, Temperature, Salinity)

We can see in the deeper layers of the MYOCEAN data (> 600 m) the salted water tongue coming from the Mediterranean as it becomes stronger at depth. Silbo  actually encountered one of the jet/finger/filament some days ago as we can see in the currents, salinity and temperature fields at 600 800 & 1000 m.

MYOCEAN Current Fields

MYOCEAN Eastward Component of Currents

MYOCEAN Temperature

MYOCEAN Salinity

Looking ahead, the currents are turning and soon we should find a river flowing south (SE) which is shown by all the images above, so lets cross our fingers and see what happens!

Finally, I would just like to acknowledge Silbo’s most recent accomplishment of entering the VIIIIG club as he has officially flown 4,000+ km while taking on the first leg of the challenger mission.

Nilsen Strandskov, Antonio Ramos, & Oliver Ho

Hey all,

In the midst of St. Patrick’s Day, Silbo is continuing on his way on his voyage through the eddy solar system.

Our goal for this weekend and into the early part of next week is to line silbo up between the middle-right side of the green arrow shown in the image above.  The plan is to ride the sun (which has over the past couple days split from a single large eddy to two smaller ones changing the currents in our most recent position) around and to the east.  The combination of the counter clockwise spinning sun with the clock wise spinning warm eddies encircling it have created a path that will hopefully hold its form as we reach it.  We also hope this plan will raise our speed as the effects of this configuration is similar to a pitching machine for baseball/tennis etc. where the two adjacent eddies spinning in opposite directions create a super powered  current.  So as we close in, we must fasten our seat belts, cross our fingers and hold on tight as we may get a huge boost of speed over the next couple days.

For now Force Wind Sea & Honor all

Nilsen Strandskov, Antonio Ramos and Oliver Ho

Hey All!

Well Silbo is continuing on his way and now making much better progress!  Since receiving a new way point yesterday morning, Silbo has flown roughly 25 km, compared to the ~50 he flew thursday-monday.

To compliment the decision our team made when deciding on the new way point, our friend Daniel Hernández, Josep Isern, Enrique Fernández and the rest of the team from ROC-SIANI group at ULPGC provided us with a simulation that made an estimation on the progress Silbo can make with the new way point compared to the old one using a 3 day estimation of marine conditions based off of the hycom model.

This path planning simulation shows Silbo flying an average of 18 km/day with the new way point compared to 8 km/day with the old flying into the head current.

With the hope of the new way point working as well as the simulation predicts, we hope to now ‘surf’ the large cold core sun eddy to the south around and to the east and use the smaller warm core planet eddies to head east towards Madeira.

Silbo’s projected path through the solar system of eddies to the south

The path highlighted in the image above provides silbo with a well beaten trail of currents that lands him pretty close to the western shores of Madeira where our friends at PLOCAN hope to deploy some drifters along with conducting an inspection of the glider and providing any support that may be needed.  Given that Silbo can maintain the speed estimated in the simulation of 18km/day, he would reach that point in roughly 6 weeks.

Unfortunately this would only hold true if these conditions remained the same.  The ocean is one of the most rapidly changing environments on the planet and so silbo will need to keep up a good pace while the teams in the Canary Islands,   TWR, and here at Rutgers continue to keep an eye on the most advantageous way points and flight patterns to make sure we stay in the best currents.  Since March 8th when Silbo was deployed, the large warm core eddy that we are on the outer edge of has migrated about 55 km to the south east.

Unfortunately, I do not have as accurate of a reference point as with this eddy as it started out with its center near Santa Maria for others, but they have noticeably moved as well.  An example being the warm core eddy planet south of the cold sun has been edging further north.  Seeing this, we must do our best to watch how these eddies are moving and try and aim silbo not only with how the currents are being shown, but with some insight on how they may shift in the near future.

Nilsen & Antonio

Hey All!

Well Silbo has been back in the water now for over 4 days now, and although he has been making steady progress, it has been quite slow, however we are moving further away from the island traffic which is becoming less of a threat.

Ship Traffic for March 11

With the way point set on Madeira, we have been at the will of a strong head current that is the product of the strong clockwise spinning warm eddy to our north and another to the east combined with the large counterclockwise spinning cold eddy to our south.  These eddies are shown below in the three road maps we are using: HYCOM, NLOM/NCOM, and MYOCEAN.

HYCOM Sea Surface Height and Currents for March 11

NLOM SSH and NCOM Currents for March 11

MYOCEAN 96 hour averaged forecast of SSH and Currents

The first two images of the hycom and nlom/ncom models both show the solar systems of eddies that are the cause of Silbo’s strong head current.  The third image from myocean is a 96 hr futurecast of the sea surface height and currents conditions that shows the persistence and strength of eddies over the next three days.

The eddies have even caused similar patterns in the salinity, temperature and density seen here in the hycom imagery:

HYCOM density for March 11

HYCOM Salinity for March 11

HYCOM Temperature for March 11

Similarly, Antonio has provided us with the MYOCEAN forecast for the salinity at 1000m.

MYOCEAN Salinity for 1000m

At 1000m depth, we see a number of ‘meddies’ or eddies produced from the introduction of super saline water of the Mediterranean colliding with the fresher water of the North Atlantic.  These will be important to keep an eye on for piloting as we may try experiments of flying between 500-1000m to avoid unfavorable currents closer to the surface.

For now, we agree that the best course of action is to change the waypoint to the south to try and get out of this strong head current and to move our way through the solar system of eddies to best continue on our way to the Canaries

New proposed way point of 34 N 23 W

Force Wind Sea and Honor

Nilsen, Antonio & Oliver

Hey All,

Here are the pics from the deployment!

Silbo and the APEX float that was deployed. photo credit: Ben Allsup, Teledyne Webb Research

Chris DeCollibus of TWR and Silbo on the dock before deployment. photo credit: Ben Allsup, Teledyne Webb Research

Test Dive photo credit: Ben Allsup, Teledyne Webb Research

The Bear is About! photo credit: Ben Allsup, Teledyne Webb Research

If there is one important lesson we have learned through the years, it is that the more resources the better.  So now with the beginning of the new leg of this mission, we have a number of products we will be using to get Silbo to his destination and for future gliders involved with the Challenger Mission.  First off, we will continue using the NLOM/NCOM/MODIS data provided to us by ULPGC.  NOAA is providing us with access to their new operational global HyCOM forecast system.  Thanks to Antonio, GEOEYE and Seawifs will provide us with some new products that will prove to be a huge help while we are out in the open waters, however when we eventually move east of the 20˚W meridian, we will be in range of Spain’s ROM data which will give us very high definition imagery and data.  Finally, also supplied by Antonio, we will have a forecasting system that will give us not only real time data, but predictions up to 96 hours into the future!  Seeing how much our friends from across the ocean provide, it is hard to imagine how we could pull off missions of this magnitude without international collaborations- something that will be key for the future when we take the challenger gliders around the world.

Bathymetry contour map of the sea floor between the Azores and Madeira

The image above shows another map of the bathymetry which compliments the maps I have posted in the past showing that although there are regions of protruding rock from the sea floor, there are no land marks that come close to 1000m from the surface.

The following four images are from the HYCOM model showing currents overlayed on Density, Salinity, Temperature, and Sea Surface Height.  All layers show the eddy solar system discussed earlier that Silbo is currently battling.

HYCOM Sea Surface Density & Currents

HYCOM Sea Surface Salinity & Currents

HYCOM Sea Surface Temperature & Currents

HYCOM Sea Surface Height & Currents

The next image is of the NLOM/NCOM data which show a similar pattern as the HYCOM of the eddie system.

NLOM Sea Surface Height overlay with NCOM Sea Surface Currents

Finally, I will leave everyone with the time series profiles that are being freshly compiled as Silbo makes his way from the Azores to the Canaries.  The following are two links from John Kerfoot (our data architect) where the scientific imagery and engineering diagnostic data can be found

Density recorded by Silbo

Salinity recorded by Silbo

Temperature recorded by Silbo

Sound Velocity through water recorded by Silbo

Again a special thanks to Ben Allsup and Chris DeCollibus for their hard work on prepping Silbo, getting him back in the water and getting such excellent pictures!

Force, Wind, Sea & Honor to all!

Nilsen Strandskov & Antonio Ramos

Hey All!

Well it is official: Silbo is back in the water and on his way to the Canaries!  Ben and Chris departed from Ponta Delgada last night and spent roughly 26 hours on the boat sailing out to the deployment location where they put Silbo and a buoy into the water

Now we will resume our posts guiding this glider to its home in the Canaries over the next few months.  There is about 1400 km between Silbo and our target which we estimate will take us until about mid may as our projected recovery date.

Looking at the bathymetry, it seems like we are in the clear.  From our current location on there doesn’t appear to be any dangerous land scape.  This means we should have no problem with running aground or wasting battery by running the altimeter.

It also looks like Silbo has his work cut out for him already.  Both HYCOM and the NLOM/NCOM models are showing not the most favorable currents, and the return of the solar system eddies.

HYCOM model of Sea Surface Height and Surface Currents

NLOM model of Sea Surface Height and NCOM model of Currents

It seems Silbo is between the bottom of a warm core eddy (clockwise spin) and the top of a cold core eddy (counterclockwise spin) resulting in a strong push to the northwest.   Depending on how this eddy system evolves we may need to make a decision on whether we set the way point to fight these currents or to allow ourselves to ride the eddy south and around the west side of the cold core eddy.  But we will discuss this tomorrow and I will put up another update.

Tomorrow will also bring a number of pictures from the deployment by Ben and Chris.

Force Wind Sea & Honor and welcome back Silbo!

Nilsen & Antonio

Hey all,

This past weekend brought us some beautiful weather, but even more amazing news.  Ben Allsup and Chris DeCollibus from Teledyne Webb Research have arrived in Ponta Delgada where they began their hard work to prepare Silbo for the next stretch of the mission.

Silbo with his new extended battery bay. Photo from Chris DeCollibus

For this next leg, Silbo has been modified to a stretch deep glider, meaning a second battery bay has been added to buy us extra time in the water on our way from the port of Ponta Delgada to the beaches of the Canary Islands.  Over the past couple days, silbo has gone through a number of tests to make sure he is ready to tackle the remaining ~1350 km of this mission.  While our team now in the Azores has been working on that, we have begun looking at the conditions for the deployment.

So far, we have two options for deployment: dropping silbo off along his track from last december or sailing east of Sao Miguel and heading south from there.  The meteorological and marine forecast and boat availability will dictate which location we choose to deploy from.

Antonio gave us a detailed marine and atmospheric forecast highlighting windows for deployment.  Our main window we plan to shoot for is between tomorrow, Tuesday 6th to Sunday 11th, where Antonio pointed out a long stretch of calm seas and nice weather with the most ideal conditions being on Friday 9th.

Next we looked at the bathymetry of the region to see where it will be deep enough to fly most efficiently.

In the bathymetry maps above, the blue color represents depths that are >1000m which allows Silbo to fly freely without us needing to turn on the altimeter, saving us battery.

If we can sail outside of the red circle prior to deployment, we should be able to fly to the full 1000m depth with no problem bathymetry wise.  Next we look at currents from the hycom and ncom models.

Hycom Sea Surface Height & Currents

NCOM Currents from 3/3

NCOM Currents from 3/4

Both models above show a pretty strong current that wraps through the islands causing a cyclonic current around Santa Maria(Island to the south, center of the yellow eddy in the Hycom image).  It looks like if we were to go the south east route, we would have to go pretty far out in order to avoid being pushed back into the archipelago.  However if we go out to the east from Sao Miguel, we can ride this current to the east and then south around the warm eddy seen in the hycom picture.  Evidence of this pattern is also seen in the currents & salinity google earth movies that Antonio sent out last month that showed a day by day evolution of the conditions from Jan 3 through Jan 28.

Finally, we have been keeping an eye on the ship traffic around the islands to make sure we don’t deploy silbo in the middle of a heavily traffic shipping lane.  Our main tool for doing so is the AIS (Automatic Identification System) data provided by Localiza Todo which provides us with near real time images of what ships are where in the ocean with forecasts of where the ships will be over the next hour.

The red circle is Ponta Delgada and we’re roughly 1,400km from the blue skies and sandy beaches of the Canary Islands; yet as you can see, the road won’t be easy. Although we’re still a ways away from our destination, countless ships are in our way; but as we get closer, we’ll determine how to slip past them.

Zooming in on the Azores, Sunday afternoon was pretty slow with very little movement to the south east of Sao Miguel.

Ship Traffic Afternoon of March 4

However, this morning the area is looking much more lively so we may want to sail a bit further out of the way to make sure Silbo doesn’t experience any close encounters that could potentially end the mission all together.

Ship Traffic Morning of March 5

Given this information, we will continue discussing what we want to do and will soon make a decision on where and when we will deploy.  We will leave you with a truly inspirational photo taken by Ben Allsup of Silbo during one of his tests.

Check back soon for more updates

Force Wind Sea & Honor

Nilsen, Antonio & Oliver