Please select your home edition
GJW Direct 2020

Atlantic to Mediterranean: A historic 5,000+ nautical mile voyage for science

by Saildrone 22 Jul 2020 10:10 UTC
Map of 2019-2020 ATL2MED mission highlights and overview of the carbon data. © Saildrone

On July 17, 2020, two Saildrone unmanned surface vehicles (USVs) known as SD 1030 and SD 1053 completed the first-ever Atlantic to Mediterranean mission. This historic nine-month voyage began in Cabo Verde, off the coast of West Africa, entered the Mediterranean Sea through the Strait of Gibraltar, and finished in Trieste, at the top of the Adriatic Sea.

The distance from deployment to retrieval, as the crow flies, was more than 5,000 nautical miles (9,260 kilometers or 5,754 miles). However, SD 1030 and SD 1053 actually sailed a combined distance of some 15,015 nautical miles (27,810 kilometers or 17,280 miles).

The mission was a public-private partnership between Saildrone and 12 oceanographic research institutions and universities from seven countries. The mission was conducted in two phases: Phase 1 was an eddy survey near Cabo Verde led by the Helmholtz Centre for Ocean Research (GEOMAR) based in Kiel, Germany, and Phase 2 focused on cross-calibration of CO2 measurements at fixed ocean stations led by the Integrated Carbon Observation System, Ocean Thematic Center (ICOS OTC) based in Bergen, Norway.

Researchers from Ocean Science Centre Mindelo (OSCM), The Oceanic Platform of the Canary Islands (PLOCAN), Balearic Islands Coastal Observing and Forecasting System (SOCIB), Instituto Hidrográfico (IH), Sorbonne Université's Laboratoire Océanographique Villefranche (LOV), Le Centre Nationale de la Recherche Scientifique (CNRS), Istituto Nazionale di Oceanografia e Geofisica Sperimentale (OGS), Istituto di Scienze Marine del Consiglio Nazionale delle Ricerche (CNR-ISMAR), and Istituto sui Sistemi Intelligenti per l'Automazione del CNR (CNR-ISSIA) ran regional sub-missions, including comparisons with moorings, gliders, and other assets.

"This was an incredibly ambitious mission that posed numerous challenges along the way. The ~5,000-nautical mile voyage had to deal with rapid marine growth in tropical waters, crowded shipping lanes in the Strait of Gibraltar, light winds, strong currents, transiting nine different EEZ's and interacting with six different navies. However, despite the challenges, we're thrilled to announce that both vehicles have now arrived in Trieste, having completed all of the mission's primary and secondary objectives," said Saildrone founder and CEO Richard Jenkins.

"The COVID-19-transformed world they find upon arrival in Trieste is a very different place than they set sail in back in October, but they sailed on, unaffected by what was going on in the world around them. This voyage has been a great demonstration of the resilience of unmanned systems to continue essential ocean science during troubled times," Jenkins added.

Mission highlights

The saildrones were deployed from the Canary Islands in October 2019 and transited south to Cabo Verde, off the west coast of Senegal, where they participated in the #MOSESeddyhunt, a multicomponent field study involving a team of chemists, biologists, and physicists on board the German research vessel Meteor and a variety of surface and underwater autonomous vehicles, floats, drifters, and an airplane. The saildrones were used to scout for ocean eddies and to conduct high-resolution surveys of certain aspects of the eddies.

Once the eddy survey was completed, the saildrones moved on to the second phase of the mission collecting data at nine fixed ocean stations for cross-calibration and validation: CVOO (Cabo Verde), ESTOC (Gran Canaria), LION (France), ANTARES (France), DYFAMED (France), W1M3A (Italy), E2M3A (Italy), PALOMA (Italy), and Miramare (Italy).

On their way to the Mediterranean Sea, the saildrones sailed several laps around MONIZEE, Portugal's oceanic buoy station managed by the Instituto Hidrográfico.

Escorted by a patrol boat from the Spanish Armada and a research vessel from the University of Cadiz, SD 1030 and SD 1053 sailed through the Strait of Gibraltar to enter the Mediterranean Sea—the first autonomous wind-powered vehicles to do so. They then headed north toward Spain's Balearic Islands to perform a sub-mission in partnership with SOCIB, which included monitoring oceanographic conditions in the area of a tagged sea turtle navigating near the strong anticyclonic eddy south of Ibiza.

From there, the saildrones headed toward the French EEZ for a saildrone-glider inter-comparison study along the Nice-Calvi Line in partnership with LOV.

Working with OGS, the saildrones completed several sub-mission objectives in the Tyrrhenian and Adriatic Seas. They collected data about potential CO2 emissions to estimate CO2 air-sea exchanges in an area of volcanic activity around the Aeolian Islands before circumnavigating Sicily entering the Adriatic Sea through the Strait of Otranto. They collected data near the E2M3A ocean station over the South Adriatic Pit and completed a saildrone-glider inter-comparison study along a transect extending from Italy to Croatia before heading north toward the Gulf of Trieste to complete the final objectives of the mission.

Throughout the mission, the ICOS OTC data group helped with processing the carbon data and forwarding it to the ICOS data portal (click to view SD 1030 data or SD 1053 data) and Copernicus in near real time.

"We're grateful and happy for the cooperation with Saildrone. The team was very helpful and solutions-oriented, which was important for such a long-lasting mission as ATL2MED. We were also quite impressed by the amount of effort they put into piloting the saildrones—do they ever sleep?!" remarked Dr. Ingunn Skjelvan, a research scientist at NORCE Norwegian Research Centre and Bjerknes Centre for Climate Research, and principal investigator for station certification at ICOS.

The two last fixed ocean stations visited by the saildrones were the ICOS stations PALOMA and Miramare (MAMBO1). Paloma is located in the Gulf of Trieste and Miramare is right off the coast of Trieste in the Miramare Marine Protected Area, the first marine nature reserve created in Italy, in 1986, and home to a rich biodiversity of marine organisms. Importantly for surveying in such fragile marine areas, saildrones are powered by the wind for forward propulsion and solar energy to run the onboard instruments. They carry no pollutants, no fuel, emit no discharge, and, as sailing vehicles, they are silent and unobtrusive.

The Gulf of Trieste is an area subject to riverine inputs and strong seasonal variations —more than 20 degreesC from winter to summer—that strongly affect the variability of the CO2 system. During the winter, the North Adriatic Dense Waters contribute to the physical pump that absorbs CO2 and transfers it to deeper waters.

"A better understanding of these processes is important for evaluating the potential impact of coastal acidification in the region, and the data may also help address the spatial variability of CO2 air-sea exchanges in an area affected by riverine discharges," said Dr. Michele Giani, a senior researcher at OGS responsible for the Miramare station. "Our research is based on the measurements at fixed points, therefore all the data that contributes to measuring spatial variability around our stations can contribute to improving understanding of which processes are best detected at the observational sites. The data will be integrated into our ongoing research of the drivers of the carbonate system temporal variability in the northern Adriatic Sea."

Next steps

The Mediterranean Sea is considered to be a small-scale ocean in which many of the processes found throughout the world's oceans occur, making it especially interesting for physical, climatic, and environmental studies. It is a highly productive region, much more so than anticipated, requiring a couple of service stops throughout the mission, despite the use of the latest anti-biofouling technology. The mission took nine months from start to finish and will serve as a blueprint for how public and private institutions between nations can work together to advance ocean observations.

"The level of productivity of the Mediterranean was a surprise, but the speed and efficiency of the pit stops we made in Cabo Verde, France, and Italy are a testament to the fantastic international collaboration of this mission—especially with the added challenge of the COVID-19 pandemic," said Saildrone COO Sebastien de Halleux. "Now the team will be working hard to ensure this series of observations is continued over time supported by funding from public and private sources."

Dr. Skjelvan said that for ICOS OTC, the use of the saildrones as validation platforms was the most useful part of the mission: "The CO2 validation data collected will help us certify the fixed stations within the ICOS European infrastructure project. A certified station provides data of the highest possible quality, and thus, underpins the main goal of ICOS. But it's important to mention that the additional data collected during this mission is incredibly useful for the scientific community as it contributes to our process of understanding the ocean and air-sea interface."

Saildrone is grateful for the support of its sponsor and scientific collaborators on this remarkable mission. Saildrone would also like to say a special thank you to the Spanish Armada for escorting SD 1030 and SD 1053 through the Strait of Gibraltar and numerous local authorities who assisted with retrieving and servicing the vehicles along the way, especially when Saildrone staff was unable to travel. We would also like to thank the Italian Navy and the Harbormaster's Office in the Port of Trieste for their collaboration and surveillance of the saildrones during their presence in the Gulf of Trieste, as well as the Port Authority, which has provided a berth for the saildrones upon mission completion.

Despite COVID-19 travel restrictions, Saildrone has continued to operate several missions in the Atlantic and Pacific, including the Alaska pollock survey in the Bering Sea for NOAA Fisheries and Saildrone's first bathymetry mission in the Arctic in collaboration with TerraSond on behalf of NOAA's National Ocean Service (NOS).

ATL2MED was an open-data effort generously sponsored by PEAK6, a private technology and investment firm started by Jenny Just and Matt Hulsizer. Atmospheric and oceanographic data will be available to the public on Saildrone's data portal and/or on the European Marine Observation and Data Network (EMODnet) and Surface Ocean CO2 Atlas (SOCAT). We encourage scientists, researchers, and students to download and analyze these data sets. If you have used Saildrone data for a published paper or if you would like to provide feedback about data quality, please contact us at data [at]

See all ATL2MED news:


Giulia Basso, "Dalle Canarie a Trieste, i droni a vela arancioni in navigazione per scoprire i segreti del mare," Il Piccolo, May 5, 2020

Björn Fiedler, "#MOSESeddyhunt: Segelnde Messroboter Gesichtet / Sailing Measuring Robots Sighted," Cape Verde Blog, Ocean Science Centre Mindelo, accessed July 20, 2020

"ICOS Ocean Stations Network," Integrated Carbon Observation System, accessed July 20, 2020

Related Articles

Is the Southern Ocean absorbing or emitting CO2?
Robot's epic voyage provides clues When an uncrewed, instrumented robot circumnavigated Antarctica during the winter of 2019, it marked a technological triumph over some of the fiercest marine conditions on Earth. Posted on 17 Feb
Saildrone launches 72-foot Surveyor
Revolutionizing ocean seabed mapping The new Saildrone Surveyor is the world's most advanced uncrewed surface vehicle, equipped with an array of acoustic instruments for high-resolution shallow and deep-water mapping. Posted on 13 Jan
Case for global ocean carbon observation network
Saildrone is seeking impact partners to operationalize its USV platform for the benefit of humankind Since 1958, the Global Carbon Budget has tracked anthropogenic CO2 emissions and their redistribution among the atmosphere, ocean, and land. Annual budgeting is necessary due to large year-to-year variability in CO2 sources and sinks. Posted on 16 Dec 2020
Saildrone USVs complete Alaska Fisheries Survey
Data collected by a fleet of Saildrone USVs will inform Alaska pollock fish stock assessment Saildrone deployed three unmanned surface vehicles (USVs) for the 2,000 nautical mile transit from San Francisco to the Eastern Bering Sea just nine days after the last-minute contract was signed. Posted on 13 Dec 2020
Winter storm chasing to improve weather forecasts
Saildrone deploy a vehicle with specially designed wing to chase hurricane-strength winter storms Hurricane track and intensity forecasting has steadily improved in recent years with data from satellites, buoys, and sensors dropped from aircraft flown into the developing storm. Posted on 24 Nov 2020
Saildrones could support US Coast Guard
A fleet of six were launched from Hawaii to demonstrate Maritime domain awareness (MDA) is the effective understanding of anything associated with the safety and security of the global maritime domain, including illegal fishing, drug enforcement, and limiting intrusion into protected areas. Posted on 18 Oct 2020
Saildrone completes first Arctic mapping mission
Four saildrones sailed 8,000nm round trip from San Francisco to the Canadian border Accurate bathymetry of the Arctic seafloor is key to maritime safety, economic development, and sustainability efforts in the region. Posted on 16 Oct 2020
Ecosystem changes put pressure on data collection
Saildrone USVs enabled Alaska Fisheries Science Center to perform the 2020 Alaska pollock survey Saildrone's fleet of unmanned surface vehicles (USVs) is a cost-effective tool to help fisheries managers meet and expand their mission. Posted on 22 Aug 2020
USCG to test Saildrone autonomous MDA capabilities
Saildrone is using a specially built camera system and advanced acoustic technology Maritime domain awareness (MDA) is the effective understanding of anything associated with the safety and security of the global maritime domain, including illegal fishing, drug enforcement, and limiting intrusion into protected marine sanctuaries. Posted on 19 Jul 2020
Mapping arctic seafloor with autonomous vehicles
Testing ability of Saildrone USVs to map the US exclusive economic zone off Alaska's North Slope It was a treacherous journey—along the west coast of Greenland, weaving through Canada's Arctic islands, and then southwest along Alaska's North Slope and through the Bering Strait—and even in the summer, it was mostly blocked by impenetrable sea ice. Posted on 12 Jun 2020
Stoneways Marine 2021 - FOOTERUpffront 2020 Foredeck Club SW FOOTERHighfield Boats - SWC - FOOTER