4/22/2024

Sentinel Mission Blog: Entry 4 – April 23rd

Welcome back to the Sentinel Mission Blog! You may remember that in last week’s post we talked about some of the hazards around our launch and what steps we would take to ensure that it would be successful. As we get closer to our launch date, it’s critical that we spread the word about our Mission. Thankfully, we have a day set aside especially for that: April 23rd.

So, what exactly will we be doing on April 23rd? To put it simply, we will be having a wide variety of people present during our class time. From 8:30 – 9:50, we will have guest speakers that range from Rutgers Administrators, Teledyne and NOAA Representatives, our correspondents in the countries that we’ll make our stops in, to our very own classmates and students.

Now that we have an idea of what April 23rd is going to look like, we should get more specific with what we will actually be happening. First of all, The President of Rutgers, Jonathan Holloway, and the Dean of the School of Environmental and Biological Sciences, Laura Lawson, will be giving a brief introductory speech and comments.

Once they finish, We’ll move on to our next guest speakers, Craig McClean and Trisha Bergmann from NOAA. This class, Topics in Marine Sciences, has had a relationship with NOAA since its inception. Afterall, they were the ones who officially challenged us to cross the Atlantic with a glider in 2009!

After they finish, we will have some representatives from Teledyne Marine, Clayton Jones and Shea Quinn, introduce the Sentinel Glider. Once they say a few Words, they’ll christen the glider with some seawater!

Once Shea finishes her speech, it’ll be time for the efforts of the students throughout the semester to be revealed in our class presentation! We’ll be discussing a variety of topics, such as, the Sentinel Mission, the Sentinel Glider, any trinkets that we’ll put inside the glider, the route we’ll be taking, the hazards we’ll be dealing with, outreach, and more.

After our class presentation finishes and we have a short Q&A Session, we’ll move on to our last section, Comments from some of our International partners.

From Spain, we have Ana Mancho, who leads the Geophysical Dynamics Group at the Instituto de Ciencias Matematicas, Enrique Alvarez, who is the head of the Physical Oceanography division at Puertos Del Estado, Antonio Ramos, who made the Glider position prediction system Pinzon, and Carlos Barrera, who is the Head of the Ocean-Vehicles Unit with the Oceanic Platform of the Canary Islands. From South Africa, we have Tammy Morris, who is the Senior Manager for Marine at the South African Weather Service. From Australia, we have Chari Pattiarachi, who is the Head of the Coastal Oceanography Group of the University of Western Australia. From New Zealand, we have Joe O’Callaghan, who founded Aotearoa New Zealand’s glider facility.

A big point of our April 23rd presentation is to spread the word about our journey across the world, so that we can hopefully secure some funds for our trip, and increase global knowledge about the ocean!

Alright everyone, that’s all the information we have to share for now. Be sure to check in soon for more! Sea you later!

4/09/2024

Sentinel Mission Blog: Entry 3 – First Week Hazards

Welcome back to the Sentinel Mission Blog! You may remember that in last week’s post we looked at some maps that outlined advantageous paths for our glider! This week, we’re going to be taking a look at some more maps, and this time, they’ll help us determine where exactly we should start off our journey. We’ll be launching off of the coast of Cape Cod in Massachusetts, however, Cape Cod is an area that has a lot of things that could interfere with or damage our glider, so we need to find a launch site that minimizes the risks. To assist us in this task, we will be using the Marcos Ocean viewer. Let’s dive in!

During the first week of its journey, the Sentinel Glider will face a major obstacle: avoiding shipping lanes. Off the coast of Massachusetts, where the glider will depart, there are many fishing, cargo, and other vessels traveling to and from shore. These ships move much faster than the Sentinel Glider, so if the Glider got caught in a shipping lane, its journey would end there. In order to avoid collisions with vessels, the Glider has to dive deep into the water and/or have a route planned around known shipping lanes. Once the Glider successfully makes its way off the continental shelf and into open ocean, shipping lanes are more dispersed, so the chance of colliding with a vessel is much less likely.

Another obstacle that our navigation team has to prepare for is the construction of offshore wind farms. Currently, off the coast of Rhode Island and Massachusetts, offshore wind turbines are being built. There are already some sites that are up and running as well. Both of these locations are something we are going to have to avoid. Although these sites contribute to sustainable energy goals, it is not a place we want our glider to be as it poses a high risk for our mission. Preparations made by our path planning team will help to curb this risk.

While shipping lanes are one of the many dangers that the Sentinel Mission will face, those ships tend to stay in designated “highways”, making them easier to avoid. Smaller ships, especially those used for commercial and recreational fishing, pose a greater level of risk due to the number of unknowns involved.

As seen above, a substantial amount of fishing takes place off the coast of Cape Cod, with red areas having a high volume of ships and blue areas having the least. Charting a course avoiding these hotspots in addition to all the other hazards has not been an easy task.

The center of the Atlantic lacks most of the hazards found along major coastlines, but they return as the glider nears Cape Town, the first of our stopping points. Ships off the coast of South Africa may not match the same level of danger stemming from the high volume of ships off of Cape Cod, but one factor does come into play: illegal fishing. Entire areas of the ocean become filled with unknowns, forcing the glider to take a bit of a wider route.

We’ve covered a few of the hazards surrounding Cape Cod’s coast today. Taking all of them into consideration, the best area for us to launch is around here.

The area that we pinpointed has a low fishing rate considering it’s distance to land, has a low shipping rate, and it’s in an offshore wind site that won’t have alot of activity around the time of our launch, making it a prime location to deploy our glider at!

That’s all the information we have to share with you all for now. Be sure to check back next week for more! Sea you later!

 

4/03/2024

Sentinel Mission Blog: Entry 2 – Flight Planning
Hello there everyone! Welcome back to the Sentinel Mission Blog! You may remember that in last week’s post we mentioned our flight planning group. Today, we’ll be diving into one of the tools that they use to expedite the flight planning Process– The Glider Guidance System!

The main thing that the Glider Guidance System (GGS) does to help pilots guide gliders in a dynamic ocean using predictions of the depth average currents of a given area. Depth-averaged current data is important because gliders are buoyancy-driven, and as they move by flying up and down through the water column (with a vertical range of 1000 meters) by changing their density, the systems profile they “feel” the depth-averaged currents in the ocean. Therefore we need a water column average current estimate to predict the potential glider flight. The vast majority of ocean currents do not flow in the same direction over depth, and surface currents may even have direct opposite counter currents hundreds of meters beneath them. Therefore, we are actively using a newly developed (by Rutgers Operational Masters Student Salvatore Fricano) Glider Guidance System that provide us with depth-average current magnitudes for helping us choose the best path for Sentinel for the glider maximizing efficiency and when possible saving power in the glider batteries by surfing currents in a positive direction to our target.

Now that we have established the purpose of the GGS, we should find out how it achieves its function. Given the working area for a mission (latitudes, longitudes, and depth range), the GGS can get real-time data from a few different ocean models., those models being, RTOFS, CMEMS, and GOFS. RTOFS is NOAA’s model, CMEMS is the European Model, and GOFS is the US Navy’s Model.

These models compute point-values for ocean currents which are spaced out on a grid across latitude, longitude, and depth. The latitude and longitude grids are usually well spaced, but the depth positions at which data points are calculated tend to vary based on where strong temperature and salinity gradients in the ocean are. This happens because all ocean physics equations are based off of gradients, which results in the depth point values being unevenly spaced. Because of this, the average of the depth point values over the latitude and longitude are improperly weighted and therefore unusable.

Thankfully, we have a solution for this problem: Interpolation! Interpolation allows the GGS to fill in the intermediate values between 2 points values over depth. Since GGS interpolates to a 1 meter resolution, we can take the raw ocean data from the model we’re using, which, for example, could only have 100 data points scattered around 1000 meters of water, and increase the resolution so that we have one data point per meter of depth! Since we now know what the ocean is modeled to look like within our range, we can then average those values to get the depth-average for each grid position!

That whole process we just discussed was only how we got the data for one point. In order to get to our end goal of a map, we’ll need to repeat that process many times. Thankfully, we have a solution to that issue as well; vectorization.

Vectorization is a technique that lets the same operation be applied to multiple data elements at the same time. GGS will use vectorization to apply the depth-averaging method described above to every latitude and longitude positions in the model’s grid at the same time. It’s the same idea as doing a task on your own vs. doing it with a group. Doing it on your own could take a long time, but doing it with others could significantly reduce the time spent on that task! Thanks to vectorization, the GGS can compute depth-averaged ocean current data for any part of the world extremely fast! The program will then plug that data onto a map, which takes a few minutes, and the process is complete!

Now that we’ve gotten through the meat and potatoes of the GGS, it’s time for some general/miscellaneous information! Our first item here is automation. The GGS can be run manually by end users or it can be set up on a server for automation. This is done on a case-by-case basis. Automated depth-averaged current maps can be very useful for glider pilots making daily adjustments to a glider, like in an area with a high amount of current activity, such as the Gulf of Mexico, where the GGS is currently being used to support the active glider missions going on as a part of the National Academies Understanding Gulf Ocean Systems (UGOS) Initiative.

Lastly, it’s time that we look at the reasoning for the existence of the GGS. The GGS was actually inspired by the Sentinel Mission! When the first route-planners were going at their task, it became clear that a dataset that represented the full range that a glider could go was needed.

Glider pilots usually observe surface current data to plan their missions and get ocean information. However, due to the length and distance of our journey, we need to use all of the range we have access to, and since ocean currents can change with depth, the planners needed a way to represent the currents over our range of depth and any other hydrodynamical forces that the glider would experience. Thus, the GGS was conceptualized, and Sal Fricano began programming it for his Masters in Operational Oceanography Thesis! It has been in development for around 5 months, and has been developed around user feedback during its early applications in supporting glider missions, like the ones going on as a part of the UGOS initiative. After Sal defends his thesis in August, the GGS will be made publicly available as a toolbox for glider pilots around the world!

That’s all the information we have to share with you all for now. Be sure to check back next week for more! Sea you later!

Additionally, We here at the Sentinel Mission blog group would like to extend our sincerest thank-you’s to Sal Fricano for explaining the GGS! Thanks Sal! Good luck on your thesis defense!

3/26/2024

Sentinel Mission Blog: Introductory Message

Hello Everyone! All of us here at the Rutgers Department of Marine and Coastal Sciences have something exciting to share. Introducing… The Sentinel Mission! This will be the first ever mission of an autonomous glider to circumnavigate the world, and we are going to be the ones to do it. Pretty neat right? Let’s start off with a bit of background information: what is a glider?

Image of Rutgers Glider

The Slocum Autonomous Underwater Gliding Vehicle is a robot that moves along the water column by climbing and diving down through it. When one is in the water, it can collect data on a variety of parameters, such as: salinity, temperature, chlorophyll in the water, and more!

Data taken from current glider ru34 deployment

They’re usually pretty slow, with a horizontal speed of around 0.5 mph. However, Even with their slow speed they are capable of traveling great distances! When we’re sending a glider on a mission, we try to ride any currents that are going in the same direction that we are in order to increase our speed and decrease battery usage! A big example of when we used strategies like this was 2009, when we sent a glider all the way across the Atlantic Ocean!

Image of people operating the 2009 glider from the RUCOOL Room at Rutgers

The glider being used for our mission was built by the Teledyne Webb Research Corporation. It is their Sentinel Model, which will eventually be commercially available.

Slocum Sentinel Glider

In this introductory post about the Sentinel Mission, we’re going to be covering what we’re doing, how we’re doing it, and why we’re doing it. Let’s get started!

What we’re doing

The purpose of the Sentinel Mission is to send a glider to circumnavigate the globe. Although glider technology has progressed since 2009, we aren’t at a point where we have the battery power to go around the whole world on one charge. This caused us to need to make a few stops on our journey. However, our stops serve another purpose as well; They allow us to visit our partner universities and allow us to give educational talks about the glider to bring awareness to the mission.

Map of the current flight plan of Sentinel Mission

The first part of our Mission will be taking us from Cape Cod, Massachusetts to Cape Town, South Africa. After that, we will head from Cape Town to Perth, Australia, and then to the Falklands, an island off the coast of South America. Lastly, we’re headed from the Falklands back to Cape Cod. This trip should take around 4 years and we will be launching this summer.

How we’re Doing it

A few things are necessary for our mission to be successful. As stated above, the glider is not very fast. To remedy that, we’ll be utilizing any currents that travel in our desired direction, like the Gulf Stream in the Atlantic Ocean. Our utilization of currents is pivotal as the glider can be taken from its base speed of around 30 km/day to over 150.

Map of the Gulf Stream and other currents in the Atlantic Ocean

From Cape Cod, we’ll be riding along the Gulf Stream for a while. We have a very talented crew working on our flight path, so they will be the ones in charge of deciding the most efficient path to take. We will be making a few stops on each part of our journey to check in on and recharge our glider. It will be imperative to be in contact with people who will be able to change our batteries and scrub off any biofouling that may affect the glider’s efficiency.

A computer rendering of barnacles growing on the glider taken from the Atlantic Crossing Glider Documentary

Why we’re doing it:

Why send a glider across the world? Water makes up 71% of the Earth’s surface. Despite how much of our planet is covered by the ocean, only 5% of it has been explored. Sending a glider  around the world can provide a new perspective on how our ocean works while exploring the unknown. Another goal of the Sentinel Mission is to connect people around the world, just like our ocean does. By making stops at some select locations during its trip, the glider will bring local communities together and spread awareness for studying our vast ocean.

 Alright everyone, that’s all that we’ve got to share with you this week! Be sure to stay tuned for any future updates! Sea you later!

 

3/22/2024

Dear Douglas Webb,

We are a large group of undergraduate students at Rutgers University. We are enrolled in a course Topics in Marine Sciences taught by Scott Glenn, Josh Kohut, and Oscar Schofield. This course is focused on interpreting the data collected by gliders deployed over the world. Every week we start off class by looking at ocean data collected by gliders that are at sea, we analyze the data and then discuss the underlying oceanography together as a class. What is amazing is that these glider tools let us go to sea while we are still taking other classes.  As many of us are fully booked in our classes and hold jobs to pay for school, it is amazing that we still have the opportunity to explore the ocean in real time.  This is only possible because of the vision you had decades ago and the work you did to make this vision a reality. We want to thank you for giving us an amazing opportunity.

We wanted to write to you today to tell you about the Sentinel Mission. Teledyne Marine has been working diligently on the Sentinel glider and they partnered with our class for conducting the first glider circumnavigation of this planet. We have been working on this mission for the past 18 months in preparation and this is a mission that will be anchored tirelessly by undergraduate students from around the world. We have been working on everything from mapping the route, to promoting the mission to our communities, businesses, other countries and universities from around the world.
Your vision decades ago has given us so many opportunities to learn more about the ocean and teach us, the next generation, about the great adventures in exploring this ocean planet. As we embark on this global mission, we are striving to “work hard, have fun, and change the world”. We want this mission to be in honor of your legacy that has permanently changed how we can interact with the ocean. We thank you for changing how we go to school, learn, and get inspired to meet the many global challenges facing us all.  We have enclosed the sticker designed by us and really look forward to starting this mission in summer of 2024 and sharing our nautical adventures with you. Thank you Doug!

Yours truly,
The Sentinel Mission Undergraduates (Class of Spring 2024)

Peterson Baldera, Charlotte Bsile, Ireland Benson, Aiden Blanos, Gabrielle Bond, Christine Capria, Jason Cardona, Jonathan Chin, Shea Cinquemani, Sophia D’Arienzo, Terrika Davis, Jessica Defo, Justin Dirosa, Jaheem Ellison, Baylee Foreman, Tyonna Griffin, Michael Hasselmann, Sarah Keppler, Ezekiel Kloza, Tolga Kose, Shea Lawless, Matt Learn, Karolina Leleniewski, Amanda Lemasters, Christopher Maderia, Brendan McCann, Grace Mchugh, Helena Messihi, Elizabeth Morocho, Jefferey Mowen, Kenneth Navarrete, Hailey Nowak, Hirkari Oshiro, Giaminh Phan, Ashley Rosales, Victoria Samuel, Luis Saula, Sonia Sharma, Zoe Sousa, Abigail Stisi, Jessica Stochel, Greg Wareham, Keva Wilson, Marc Youhana, Devorah Zambas