Historically, algal blooms usually disappear a few weeks after they develop. But, the one currently off the West Coast began in May. Vera Trainer is a researcher with the Northwest Fisheries Science Center in Seattle.
"We've had sustained warm weather, few storms so they are staying put in our coastal environment this year."
Trainer says this bloom appears to be one large connected body. In the past a smaller bloom might form in California, then another later in Washington. She says it's unusual to have a contiguous body stretching up coast from Santa Barbara all the way to Alaska.
"Whether this bloom is providing a window of things to come for the future, and a world that we can envision under climate change, I think that's a distinct possibility."
In nearly 25 years of research, Trainer says she's never seen an event like this. She says scientists are finding different types of algal blooms, in larger numbers in new places.