Sequoia Scientific

Tom’s Cruise

Sequoia on French Research Vessel

Namibia, Africa

Tom’s Cruise Summary: My time on Tara was both challenging and rewarding. It was a challenge to manage such a large suite of instrument onboard the ship. I’m fortunate to have prior experience onboard Tara. However, there is always new equipment onboard that you must learn about. During our leg, some instruments did break down and require repair. The limited supplies on a small ship can make this a real challenge. However, we were always able to make the repairs and get everything back online. One of the most rewarding parts of the trip was working with a multinational crew of sailors and scientists. The crew of Tara is composed of highly intelligent and motivated individuals. This creates a very spirited and dynamic atmosphere onboard. Even though the work can be monotonous, it was never boring. We had a very successful leg and everyone onboard is proud of the work they have done. We are looking forward to learning new information from our data in the months and years to come!


Upwelling Phenomenon – Microbiomes Mission

Watch Tom’s Cruise in Africa captured in YouTube link:




Finishing out sea cruise with a visit to the nearby African desert!

Desert near Walvis Bay


Data collection, Sequoia’s flow through instruments on TARA!  

Even though the LISST-Tau, LISST-200X, LISST-Holo2, and Hyper-bb are submersible instruments, they are well adapted for integration into a flow through system. Each instrument has a specially designed flow through chamber that allowed for easy installation on Tara. The LISST instruments operated 24 hours a day for nearly 30 days. The only down time was for cleaning. We collected nearly 2 million data points with the LISST-Tau, LISST-200X, and Hyper-bb. We transited through a wide range of waters ranging from beam-c of 10 – 0.01 1/m. Near the upwelling zone, we passed through areas thick with large diatoms. Other areas had large blooms of salps that clogged our nets. Further north on the coast of Namibia, there were large amounts of desert sand mixed into the water column. Processing data from the flow through system is ongoing. We look forward to sharing data not only from LISST instruments, but also from other optical instruments installed onboard. Tara is currently continuing its expedition up the western coast of Africa. Tara will arrive back in her home port of Lorient, France in October 2022.


Tom’s Cruise in Africa closes out! “We are now ending in Walvis Bay

Temperature map from flow through system

Tom’s Cruise this week in Africa! “We are now North of Walvis Bay, Namibia. We will complete a station near the Angola border before heading back to Walvis Bay; five more stations to go before we are finished. We finally caught some fish while we were transiting and this made for an excellent meal! We are also seeing the influence of the nearby Namib Desert. We are catching lady bugs and crickets in our nets; we are not eating the crickets” Tom states! :)

Cricket caught on TARA

Fresh Catch of the Day!

Meal of Fresh Fish

beam-c data from LISST-200X & LISST-Tau

CTD Rosette w/LISST-200X mounted below

LISST-Tau & Hyper-bb working in flow through

Aquatic Critter

Tom’s Cruise notes this week in Africa! Tom reports “We finished an inshore-offshore series of stations near Luderitz, Namibia. The area is a well-known upwelling region off the coast of Namibia and of interest to our mission. Having completed component cleaning today, the LISST instruments are working away in the shipboard flowthrough system”.

Ocean critters in jar

Research Scientist Thomas Leeuw

Marine Visitors

Logging Live Ocean Data!

“We have completed two stations near the mouth of the Orange River; tomorrow will be an offshore station (approximately 120 miles offshore). Studying and observing a large gradient in the water turbidity and particulate matter going from the river mouth to offshore. Flow through instruments have been running the whole time, yielding excellent data for the LISST-Tau, LISST-200X and other scientific instruments.”

Rosette in turbid waters

LISST-Horizon in TARA underway lab

TARA with full sails

Sailing to Saint Helena Bay, LISST instruments installed and sampling

RV TARA departing Cape Town

LISST-Tau & Hyper-bb

Sailing into the sunset

Arrival in Cape Town, South Africa

Scientist, Thomas Leeuw

Cape Town Harbor

LISST-200X – Table Mountain background

Boarding in Cape Town








Sequoia’s Research Scientist Thomas Leeuw is embarking on the TARA research vessel in support of a mission to study microbiomes. The French flagged TARA is a 35.91 m monohull sail yacht, designed for expedition and research, serving as a scientific platform to collect and study Earths oceans, rivers and climate worldwide. Installed onboard are the LISST-200X, LISST-Holo2, LISST-Tau, LISST-Horizon and Hyper-bb; all optical related instruments designed and built by Sequoia.


TARA is operated by The Tara Ocean Foundation who is the first foundation in France to be recognized as promoting the public interest dedicated to the ocean, founded by Agnès Troublé called agnès b. in 2003 and chaired by Etienne Bourgois, the Tara Ocean Foundation is leading a scientific revolution around this ecosystem.

With its associated scientific consortia, it is developing innovative and original open ocean science which, in the future, will enable us to predict anticipate and better understand climate risks and better protect biodiversity.

It uses this high-level scientific expertise and these sea voyages to raise awareness and educate young people and the public in general, to mobilize political decision makers at the highest level and to enable developing countries to access this new knowledge about the Ocean.

Mission Microbiomes is part of the European AtlantECO project, financed by the European Commission, that brings together 36 scientific institutions in Europe, Brazil and South Africa and involves 15 scientists on the ship itself. This international scientific collaboration is intended to develop a deeper understanding of the challenges linked to the Atlantic Ocean. AtlantECO will roam the Atlantic Ocean with six main expeditions, two of which will study the coasts of Brazil.

Mission Microbiomes

Research Scientist Thomas Leeuw on bow of TARA

Thomas Leeuw is a graduate of the University of Maine, where he received his Bachelor of Sciences in Marine Sciences and Masters Degree in Oceanography.  Primarily focused on optical oceanography, he is also a software developer with experience in a wide variety of languages and platforms; developing and supporting all modern software associated with the Sequoia product family. Look for updates to the TARA mission and new reports of Tom’s cruise to be posted in the weeks ahead!