Saildrones, buoys work together to monitor Hawaiʻi waters

Three Saildrone Explorers, uncrewed surface vessels used to measure ocean data, were deployed around Hawaiʻi Island, Maui, Oʻahu and Kauaʻi to evaluate ocean health across the state.

To accompany the saildrones, buoys are being set up around each island to collect critical ocean chemistry observations to better assess Hawaiʻi’s vulnerability to changes.

The University of Hawaiʻi at Mānoa, the National Oceanic and Atmospheric Administration’s Pacific Marine Environmental Lab, and the Cooperative Institute for Climate, Ocean, and Ecosystem Studies, are collaborating with Saildrone Inc. on the project.

This effort is funded by a portion of a $50 million gift from Dr. Priscilla Chan and Mark Zuckerberg to the Hawaiʻi Institute of Marine Biology in 2022 to improve Hawaiʻi’s ocean health.

Researchers deployed a new buoy off Maui in May and will set up two more: one off Kauaʻi and one off Hawaiʻi Island later this summer. They have also had two buoys off the coast of Windward Oʻahu for more than 10 years collecting data and providing researchers with a time series of water quality information. The saildrones left from Pacific Shipyards International in Honolulu Harbor on Oʻahu in March and started the official mission in April.

“The saildrones, these autonomous sailing boats, that are surveying all the way around Oʻahu and the other islands, allow us to connect the time information we get from the buoys with the spatial information collected from these moving platforms,” said Christopher Sabine, University of Hawai‘i Mānoa interim vice provost for research and scholarship.

The 23-foot ocean drones and buoys will work together to send back critical data and images in real time to scientists in Hawaiʻi and Washington State so they can assess how climate change and ocean acidification are impacting our coastal waters.

The saildrone’s integration of pH and carbon dioxide measurements gives researchers the ability to better understand whether nearshore waters are accumulating fossil fuel emissions. They will be able to develop maps from field measurements to help them look for “hot spots” of ocean acidification.

“Collecting this data is important for Hawaiʻi because it’ll tell us more about different hot spots around each of the islands, where we might want to pay attention to how the water chemistry and water quality is changing in those areas,” said Amy Markel, University of Hawai‘i Mānoa Oceanography PhD student.

The saildrones will provide information about the nearshore water quality and chemistry in a way that has not been possible using previous shipboard approaches. The drones have advanced safety protocols including automated dynamic positioning and piloting based on real-time measurements of GPS location, winds and currents; 24/7 on-watch mission managers to oversee all operations; Automatic Identification System for identifying and avoiding other vessels; and highly visible lights and markings.

The saildrones will zigzag between the island’s coastline and 5 kilometers offshore. The instruments will only monitor atmospheric and ocean properties and will not collect any data that can be used to identify people, marine mammals or fish locations. Mariners are encouraged to stay 500 meters away from the instruments.

“The saildrones look like sailboats, and they’re working very close to shore, so if you see them please don’t touch them or interfere with their operations,” said Sabine. “They are being remotely piloted and they’re operating in safe waters.”