LIHU‘E — The University of Hawai‘i at Manoa, in partnership with several scientific organizations, has released three aquatic drones into Hawai‘i’s waters, where the drones are embarking on a journey around the main islands in an effort to assess climate change’s impact on the state’s coastal waters.
Over the course of six months, three, 23-foot, uncrewed, semiautonomous surface vehicles will scan waters up to 5 kilometers off the coasts of Kaua‘i, O‘ahu, Maui and Hawai‘i Island, providing scientists with real-time data indicating whether nearshore waters are accumulating fossil fuel emissions.
“We’re all familiar with the fact that burning fossil fuels releases CO2 into the atmosphere, and that acts as a greenhouse gas in the atmosphere,” said Christopher Sabine, UH-Manoa oceanography professor and interim vice provost for research and scholarship. “But many people maybe are not familiar that the oceans are absorbing between 25 and 30 percent of all the CO2 that we release into the atmosphere.”
When that CO2 meets water, a chemical reaction between the two compounds creates carbonic acid, dramatically shifting the ocean’s pH levels and severely affecting the aquatic environment.
“We’re seeing pH levels that are lower than the oceans have seen for perhaps as long as 20 million years,” Sabine said. “And so, many of these organisms that live in the ocean evolved during a time of very stable pH … so we’re changing the fundamental chemistry of the oceans by changing the pH.”
In particular, organisms that create calcium carbonate — such as corals, oysters and crabs — find it much more difficult to produce their shells and skeletons in the acidified water, making the organisms grow slowly and ending up susceptible to disease.
“That’s the primary effect that we’re focusing on — in this case, for the Hawaiian Islands — is the impact that ocean acidification will have on our coral reefs,” Sabine said. “Because, of course, the coral reefs are critical for tourism, for protecting our coastlines from storms, for cultural practices and subsistence fishing.”
With the data accumulated through this project, researchers plan to develop maps to determine where along Hawai‘i’s waters organisms producing calcium carbonate are most vulnerable to the impacts of climate change.
The saildrones left from Pacific Shipyards International in Honolulu Harbor in March en route to Hawai‘i Island, where the project officially started on April 1.
“Previously, this type of data was only available via models, not real-time data,” said Amy Markel, a UH-Manoa oceanography Ph.D. student working with Sabine on the project. “So the saildrone data will be giving us that real-time information about the water quality.”
The project is a collaboration between UH-Manoa, the National Oceanic and Atmospheric Administration’s Pacific Marine Environmental Lab, the Cooperative Institute for Climate, Ocean and Ecosystem Studies and Saildrone Inc. The effort is part of a $50 million gift from Priscilla Chan and Mark Zuckerberg to the Hawai‘i Institute of Marine Biology in 2022 to improve Hawai‘i’s ocean health.
