Thursday, March 28, 2013

Having fun with the map viewer!

(March 28) Tomorrow, our SailBuoy will have been deployed for two weeks and it continues to collect data as planned and expected. All indicators we receive on an hourly basis are green, indicating that all sensors and components are functioning. The battery levels are still very high. 

However, we haven’t made much ground moving in the direction of the De Soto Canyon. As the image below shows, the buoy has moved to the southeast instead of sailing to the northwest following the isobaths (lines of same depths) in the Canyon like we had planned.  This image was created using the map viewer function of the Deep-C Gulf of Mexico Atlas.

 

This can be explained by wind conditions that have prevailed this past week. From Monday through Thursday, the winds were very strong and originating from the northwest (the direction in which the buoy was programmed to go). And just like a full-size sailboat, there is an angle (compared to the wind direction) that the buoy cannot sail towards (this is referred to as the “no-go area” on the image at right). If she tries, the buoy will find herself “in irons” and will drift with the currents instead of sailing. 

When the buoy starts to drift, her speed is reduced significantly compared to when she sails. Consequently, two consecutive blue dots on the map above (recorded one hour apart) will be closer to each other when the buoy drifts and farther apart when the buoy sails. By the way, I am sure you had already figured this out... but the red dot is the actual location of the buoy.

The Deep-C Gulf of Mexico Atlas is loaded with options and functionalities that makes it fun to play with. For instance, we can superimpose the SailBuoy trajectory on the currents at the surface of the Gulf of Mexico, as produced by our high resolution HYCOM model. The image below shows the surface currents for this last Tuesday (March 25). They are oriented from the northwest to the southeast and help illustrate and explain the buoy drift as described above. Of course, the currents seen here were forced and generated by the local winds, in the preceding hours. 


On the map viewer we can also plot or superimpose the temperature or salinity fields, at different depths or at the surface. We can even make a vertical section from the surface to the bottom!  Personally, I like to compare the values seen by the buoy to the ones predicted by the HYCOM model. You will see that they are very close to each other! Something else that I have noticed on the recent SailBuoy data is that the surface of the Gulf has been getting slightly colder these past days. Once gain, this is probably a consequence of the recent strong winds, which have provoked vertical mixing (with the colder waters underneath) and evaporation.  Wind is the main force for evaporation, more than the sun radiations, and evaporation has a tendency to cool the ocean’s surface. 

Today, the winds have shifted and are now originating from the southeast, as reported in real time by the meteorological SGOF1 tower, conveniently located nearby (click here to view the SGOF1 tower station information - historical data are also archived). These conditions, called “astern” are still not optimal for the SailBuoy's navigation. This is why today we see a drift to the northwest. But as soon as the wind shifts a little bit compared to the direction in which the buoy is programmed to go (northwest) then we expect to observe the buoy back in her full “sailing mode” at higher velocities (up to 1.5 m/s which is about 3 knots!) 

Check out the Deep-C Gulf of Mexico Atlas for yourself.  To map the SailBuoy's, select CMR Sailbuoy on the Base Layer drop-down menu (located in the upper left corner).  You can map its locations (points on the map) or its path.

Posted by:

Dr. Nico Wienders
Florida State University

Wednesday, March 20, 2013

And the mission begins!

The SailBuoy is finally deployed so I should be relieved, right?  The buoy is sailing towards her first waypoint.  But to tell you the truth, getting her out to sea was not as effortless as it perhaps looked.  It involved weeks of planning, organizing, testing, and rushing around. Not to mention a few unexpected bumps along the way.

Dr. Lars Hole (right) and I (on the left) took the SailBuoy
to an"All Hands" conference so members of the Deep-C
community could get a look at the vessel.
Our first challenge was to get the SailBuoy from Norway (where it was developed by CMR Instrumentation) to Florida, and then to get it cleared through U.S. Customs. That process took nearly a week, during which time we heard very little about its location and when it might arrive.  At last we were informed that our buoy was en route and I would be getting a call to set up the delivery. Alas, the call never came and we spent several days wondering if the big wooden crate containing our precious cargo had been delivered or instead was lost.  (As it turns out, there was a typo on the shipping receipt so I was not getting the calls from the delivery company.)  After several phone inquiries and still no buoy, I hopped in my car and drove to a list of potential locations in Tallahassee where our SailBuoy might have been stored upon its arrival.  Thankfully, I located it just a few hours before our Deep-C "All Hands" meeting where the SailBuoy was scheduled to be on display. It was quickly loaded up and the next morning we took it to the meeting so members of the Deep-C community could get a first-hand look at our newest device for scientific observations in the Gulf. 

The original deployment date was set for March 4. The plan was for me to meet the RV Bellows in Pensacola on March 3 and head out to sea in the very wee hours of the next morning.  This meant we only had a few days after its arrival to test it and get a system in place for our data center to receive real-time data from the buoy via satellite. 

Dr. Lars Hole and I immediately began testing the buoy's GPS reception and satellite transmissions. I worked closely with members of the Deep-C data team to set up the scripts and routines that would receive, parse, process and display the data our buoy would be transmitting. All of this needed to be done under a very tight deadline… so there were many late nights for everyone involved.  But we eventually were ready to go and... the cruise was cancelled due to bad weather!  That is always a risk in ocean research so it meant rushing to develop an alternative deployment plan.  Fortunately, the RV Apalachee was available and a new launch date was set for March 15. Special thanks to Dr. Felicia Coleman, Director of the FSU Marine Lab and the Scientific Director for Deep-C, for making their flagship vessel available on such short notice.  As our first blog posts shared, we successfully released the SailBuoy that day.  

At this point, with the SailBuoy finally deployed, you would think I could finally feel relieved... but not yet. 

The seas were calm and there was only a very light wind
when it came time to launch the SailBuoy.
After letting the buoy go, we stayed around for a bit. I sent a text message to David Peddie in Norway so he could upload the first waypoint to the buoy via the two-way satellite communication system. We stayed to take pictures, make videos, and in my case just to check that everything was working as expected.  It was a radiant and cloudless day and all we could see around us was blue. There was barely a chop and only a very light wind. This actually made me a bit nervous because as we waited alongside the buoy, it began drifting with the current rather than sailing to its first waypoint.  After another quick communication with David we surmised that the buoy's navigation system needed time to set itself up, so somewhat reassured I told Captain Rosanne to head home. 

The trip back surely was a pleasure. I think we were all feeling lucky to be on this brand new and gorgeous vessel for its maiden voyage. As we passed Bob Sikes Cut the sun grew bigger and the wind fell. The catamaran reminded me of a black skimmer, barely touching the water at the incredible speed of 24 knots. We are more accustomed to 8-12 knots on other vessels and sometimes just 2 knots on icebreakers!  And yet, no motion was detectable on the deck. What a ship!  Members of our launch team got to enjoy their lunch and rest a bit. 

I stayed outside on the aft deck, waiting for updates from the buoy (I could receive them on my cell phone). As we traveled back, the coordinates we were getting told us that the buoy continued to drift to the east-southeast with the current instead of sailing west. It was a tense few hours as David and I discussed what the problem might be and what actions we should take. I definitely was not relieved at this point. We considered the possibility of equipment failure -- perhaps the rudder was malfunctioning.  We also considered the ocean conditions.  Finally, after a few hours, we understood what was happening: the wind on that brilliant day was not strong enough to set our SailBuoy on its designated course, as a wind speed of at least 5 knots is needed.  So we opted to direct it to the south for the night (to avoid grounding on Little Saint George Island) and I stayed up all night keeping watch over her location. 

We are now five days into our mission. The winds have become stronger and the buoy is happily sailing towards her first waypoint at the entrance of the De Soto Canyon. 

The SailBuoy is sailing towards her first waypoint, to the west and at the entrance of the De Soto Canyon.

So am I finally relieved? Well, almost. Not really. I still anxiously wait for the updates from our SailBuoy to come hourly. I constantly monitor her trajectory and velocity, and check to be sure each of the sensors are working properly.  

She has a long journey ahead.  And very soon, you too will be able to follow the SailBuoy as it reports where it is and what it is finding all along the way.  You can experience some of our activities and see the transmitted data.  We expect to have our real-time tracking map online this week, so check back to this blog or visit www.deep-c.org/sailbuoy

Before I finish this entry, I would like to thank all the people who helped make the mission successful so far -- from developing the instrument, to transporting the crate with me, to brainstorming and planning the mission, to configuring the data and mail servers, to chartering the new RV Apalachee for us... so many, many things.  My warm and kind gratitude here to David Peddie, Lars Hole, Eric Chassignet, Felicia Coleman, Tracy Ippolito, Allan Clarke, Dick Snyder, Alen Michels, Bruno Deremble, John Kaba, Eric Mortensen, Kris Suchdeve, Xiaolin Zhang, Shawn Smith, Michael McDonald, Srinath Viswanathan, Arsalan Ahmed, Olmo Zavala, Captain Rosanne Weglinski, Bobby Henderson, and Chiu Cheng.

Posted by:
Dr. Nico Wienders
Florida State University

Friday, March 15, 2013

Time to launch the SailBuoy!

Assembled and ready to go...
After confirming that the SailBuoy is transmitting to the Operations Center, we are ready to launch!  

Dr. Nico Wienders helps carry the SailBuoy down to the deployment deck.

Views from the SailBuoy as it leaves the research vessel.
Members of the launch team (l-r: Kris Suchdeve, Nico Wienders, and Xiaolin Zhang)
conduct a data validation exercise before we leave it to begin its work..
Before the SailBuoy can be left to start its mission, the team conducts a series of data validation exercises.  They compare salinity, temperature and oxygen measurements taken with a handheld sensor off the side of the research vessel to data being transmitted by the SailBuoy a few hundred yards away.  Once they confirm the SailBuoy sensors are working properly, we are ready to bid her farewell and head home.  Learn more about the SailBuoy project.

Heading home after a successful launch...

Posted by:
Tracy Ippolito
Deep-C Coordinator



We are on our way!

(10:15 am) The RV Apalachee is moving at an impressive 23 knots per hour so we are already almost at the launch site.  The RV Apalachee is a brand new 65' research vessel delivered to the Marine Lab just a couple of weeks ago.  It is now the flagship of the FSU Marine Lab fleet and, as it turns out, today's research cruise to launch our SailBuoy is the RV Apalachee's maiden voyage!


Special thanks to Dr. Felicia Coleman, Director of the FSU Marine Lab and the Scientific Director for Deep-C, for making this cruise possible on such short notice.  Learn more about the RV Apalachee.

Some assembly required... Kris Suchdeve and Dr. Nico Wienders attach the sail to the buoy's hull.
Posted by:
Tracy Ippolito
Deep-C Coordinator



The SailBuoy Project begins!


(7:30am) The sun is just coming up and the SailBuoy has arrived at the Florida State University (FSU) Coastal and Marine Laboratory in St. Teresa, FL.  Members of our launch team are loading it onto the RV Apalachee.  
In the wee hours of the morning, Boat Captain Rosanne Weglinski assists
Dr. Nico Wienders and Kris Suchdeve in loading Deep-C's SailBuoy onto the RV Apalachee's deck. 

Our original deployment date was postponed due to weather.  But it looks like today's weather will be terrific -- clear skies and relatively calm seas.  Our plan is to travel approximately 65 nautical miles (nm) west to a location just south of Cape San Blas.  Assuming the launch goes well and the SailBuoy is operating properly, it will be at sea for approximately two months. During its mission, it will sail approximately 840nm on a cruise track that criss-crosses the Gulf coast, from the Florida Panhandle to West Louisiana. 

Collection and analysis of this data will help Deep-C scientists better understand how particles and dissolved substances (such as oil) are transported from the deep Gulf to the shelf waters in the northeastern Gulf across the continental shelf and the DeSoto Canyon.  Learn more about the SailBuoy project.

Posted by:
Tracy Ippolito
Deep-C Coordinator