What if satellites circling our blue planet from space could offer insight into how an invisible gas like carbon dioxide moves through coastal waters, hundreds of miles above the ocean’s surface? Scientists will be working to make this a reality as they travel from Nova Scotia to Florida on board NOAA ship Henry B. Bigelow to understand what is driving changes in our ocean’s chemistry.
During this mission, scientists and the crew aim to get a better handle on where and how fast ocean chemistry is changing along the US east coast and what’s driving these changes. The chemistry of our ocean is changing because it’s absorbing more carbon dioxide (CO2) from our atmosphere due to human activities. Carbon dioxide levels have been on a rocketship-like trajectory that began with a sharp rise in the human population in the mid-1800’s. Rapidly increasing energy and food demands resulted in a large loading of carbon dioxide into the atmosphere as growing demands were met mostly by the burning of fossil fuels and the remaking of vast areas of the land; turning them from natural CO2 sinks (i.e. trees) to sources (i.e. farmland) over the past 150 years. This increasing atmospheric CO2 is mirrored in our ocean, in a process called ocean acidification. Scientists aboard the Bigelow will be measuring the ocean and life with in it- from very young fish to corals on the seafloor- while optimizing tools to see how tiny marine plants (phytoplankton) drive changes in chemistry in coastal waters.
This 34-day mission is being led by Associate Research Professor of Oceanography at University of New Hampshire’s Institute for the Study of Earth, Oceans, and Space, Joe Salisbury. “This is third or fourth time we will be visiting some of the sites of this survey, which will allow us to more fully understand how ocean acidification is playing out on the East Coast,” Salisbury shares.
On June 25th, the ship departs from Newport, Rhode Island and steams north toward Nova Scotia. From there they’ll begin the journey south to Florida and after over a month at sea the ship and its crew will return to port. Along the way, at all hours of the day scientists and crew on board will be working to better understand how marine chemistry, plants, and animals interact from the surface to the sea floor.
This in depth exploration is made possible by collaboration among eight federal and academic institutions. “This year the range of partners involved is considerably more than past missions which will allow us to bring more science to bear to achieve a deeper understanding of acidification,” offers Dwight Gledhill, Deputy Director of NOAA’s Ocean Acidification Program.
These east coast missions take place routinely to measure how our ocean is changing over time. What will remain consistent with this year’s mission? The chemical measurements that allow scientists to get a full picture of how atmospheric CO2 is affecting our ocean. Some important additions to this year’s voyage are possible thanks to the National Aeronautics and Space Administration (NASA), NOAA NESDIS Center for Satellite Application and Research, and Fisheries and Oceans Canada (DFO) that expanded the people involved, areas being surveyed and the kind of information collected.
A broader and more in depth look:
This year the Bigelow will head further north to Bay of Fundy to understand if and how cold northern waters are affecting ocean chemistry in US waters. The team will also focus on potential hot spots for acidification, such as the Gulf of Maine and South Atlantic Bight, which extends roughly from Cape Hatteras, NC to West Palm Beach, FL. Additionally, samples will be taken from deep in the water where deep sea coral live and provide habitat in otherwise desolate waters. The team will also continue to build on chemistry measurements taken close to shore in Acadia National Park, Assateague Island, Cape Cod, Cape Hatteras, Cape Lookout, and Fire Island National Seashores, and Gateway National Recreation Area. These samples will be analyzed at NOAA’s Atlantic Oceanographic and Meteorological Laboratory.
Human powered and unmanned monitoring meet:
Another effort new to this cruise is to understand how autonomous monitoring stations like buoys, are measuring up. The Bigelow will hold side-by-side with two ocean acidification time-series stations - one in the Gulf of Maine and another off of Georgia’s coast in Gray’s Reef National Marine Sanctuary- to compare measurements taken every three hours by CO2 sensors on these moorings. Liza Wright-Fairbanks of Grace Saba's Lab at Rutgers University will also be deploying a glider with a newly integrated pH sensor to test its accuracy. In the future, this unmanned technology can help identify high-risk regions for acidification that are inhabited by commercially important species.
New questions being asked:
Near the ocean’s surface, samples will be taken in order to get a pulse on how phytoplankton (tiny ocean plants) affect the amount of CO2 in coastal and ocean waters. An array of instruments will be launched from the Bigelow to gauge how sunlight travels and reflects in surface waters, where solar-powered phytoplankton thrive.
Because this year’s mission will spend time exploring the seafloor as well, Fisheries and Oceans Canada will be exploring another gas generated at the bottom of the seafloor- methane.
“We are going to see if these methane sites have a significantly different pH (a measure of how acidic or basic) the seawater is,” says Melissa Melendez Oyola, a PhD student at University of New Hampshire, who will be handling the collection of these samples on board.
This year’s east coast ocean acidification cruise will help answer important questions and advance the understanding of what is driving changes in ocean chemistry on the US east coast. The new tools and information collected this year will ultimately help scientists to ‘sense’ phytoplankton and carbon dioxide along our coasts from space. By understanding these connections and drivers behind this shift in our ocean’s chemistry we will be able to better predict what areas of the US coast are vulnerable and how we can adapt to this seemingly invisible change.
Interested in learning what life at sea is like, and how scientists go about answering these question? Follow the East Coast Ocean Acidification Facebook page.
Learn more about all of the institutions that make this possible: