Imagine a world where every time you started your car, part of your home dissolved.
How often would you walk or bike to work?
Now stop imagining, because it’s not your house that’s dissolving, it’s the shells of oysters, clams and pteropods, a food source for many other forms of marine life.
“It’s probably not accurate to think that all fish in the ocean will perish as a result of acidification. But the marine food web as we know it – and as we are economically accustomed to – will likely be very different in ways that negatively impact commercially important species like crab, oysters, salmon,” said Burke Hales, an associate professor at Oregon State University’s college of oceanic and atmospheric sciences.
Ocean acidification – the increase in carbon levels throughout the worlds ocean – is the topic of “A Sea Change,” the February film in the Salem Progressive Film Series. Hales and George Waldbusser, an assistant professor at Oregon State University’s college of oceanic and atmospheric sciences.
The documentary follows an exploration of the problem by a bicycle-riding grandfather who was tipped off to its existence and fell in love with admittedly adorable pteropods put at risk.
Increases in the oceans’ carbon levels have dissolved or prevented the formation of some pteropods’ protective shells in the open ocean and those of bivalves – oysters and clams – in coastal areas.
“It affects coastal areas in more complex ways,” said Waldbusser, who specifically studies the effects of acidification on bivalves. “The drop in pH levels makes metals in the water more toxic and it can stunt the formation of or dissolve bivalve shells.”
The more general effect is a disruption of the food chain, said Hales.
“Fish might not all die, but we may move to a system dominated by species we don’t appreciate so much, like jellyfish and blue-green algae,” he said.
The film explores the causes of acidification and some of the long-term solutions that might reverse the process, but is somewhat ambiguous regarding whether we’ve reached a point of no return. That’s a reflection of the state of the debate, said Waldbusser.
“We haven’t been able to do enough experimentation because we’ve never reached these levels before,” he said. “We don’t know how long it’s going to take to recover or if we can.”
Hales said we probably haven’t a breaking point, but that there are areas that will continue to suffer from ocean acidification for years to come even if we were able to completely halt current carbon-producing practices. He said it’s time to start thinking about and investing in carbon dioxide removal technologies.
“Everybody needs to trim their footprint a little, and hope that others are doing the same,” Hales said. “One thing the public should start demanding is a real accounting of the net carbon dioxide emissions of their decisions – for example, how long should you keep nursing your old car along before it becomes a lesser carbon dioxide impact to junk it and have a new Prius produced? [That] doesn’t exist in any accessible form now that I’m aware of.”
“A Sea Change” will be shown Feb. 11 at the Grand Theater, 190 High St.
Tickets are $3 for adults, $2 for students. Doors open at 6:15 p.m. The screening begins at 7 p.m.