LEWES — By studying the interaction between the upper ocean layers and the lower atmosphere, a team led by Dr. Andrew Wozniak of the University of Delaware hopes to improve the understanding of climate models.
This mission is supported by an expedition to the continental shelf that departed from Lewes on Sunday.
“We’re studying different environments to see the differences,” Dr. Wozniak said. “We start right off the Delaware Bay and then go to the continental shelf and the open ocean.”
He and his team are studying the millimeter-thin layer between the ocean surface and the atmosphere, a layer full of things like plankton and pollutant residues, to find out how the surfaces interact and affect each other.
“It’s the surface of the ocean. We’re studying how the chemistry of seawater is affected by phytoplankton to see how quickly gas and particle exchange occurs,” he said.
“Plants need carbon dioxide, oxygen, methane, nitrogen dioxide and pollutants such as sulfates and nitrates from the combustion of fossil fuels to grow.”
There are discrepancies in the models currently used for such measurements, said Dr. Wozniak, and it is suspected that changes in the microlayer are at least partly responsible.
But how do you measure it? The team designed and constructed a device that can be towed behind the expedition ship. The device consists of several glass panes mounted vertically on a circular frame. As the boat moves through the water, the equipment is designed to detect the inhabitants and compounds of the layer on the glass in order to be able to recover and test the material.
“When you see a rough surface or an oil slick on the water, these are areas of accumulation of surfactant compounds that alter exchange rates,” he said.
But that’s only one piece of the puzzle.
“This is the measurement phase. The rates are important for climate change models, and in the ocean, over such a large area, it’s important to understand how things are moving back and forth,” Dr. Wozniak explained.
This mission faced some challenges from the start: it was originally scheduled for November 2022.
“We were out for two days, but then the next hurricane came, so we looked at the forecast and said forget it,” Dr. Wozniak said. “Mechanical problems with the ship held us up last year, and we had even more this summer,” delaying the trip late last month. Also, the return date depends on the weather.
But Dr. Wozniak said he and his team knew the importance of patience.
“It is important to understand how all oceanic and atmospheric processes are interconnected because our understanding of complex problems comes from understanding all aspects of the problem,” he said.
