Maybe because we're heating the oceans to boiling point?

Marine scientists are trying to find out why previously unknown blooms of toxic algae are suddenly proliferating along the California coast, killing wildlife and increasing the risk of human sickness. The mysterious blooms have recently been bigger and have occurred more frequently than ever before, an alarming trend that a team of scientists led by UC Santa Cruz is attempting to figure out.

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Scientists will also try to determine whether climate change is having an effect on the size, frequency and location of deadly algae blooms. "We can't say for sure that it is tied to something like climate change," Kudela said, "but it does seem to be spreading globally, so something is changing, and we are trying to find out what that is." Algal blooms are already known to be relatively common in the coastal waters of Oregon, Washington state and Canada. Recently, though, unusual toxic algal blooms have also been detected in the Gulf of Mexico, off the coast of Alabama, South Carolina, Florida, in Chesapeake Bay and the Gulf of Maine, according to researchers. Future outbreaks may be unstoppable, Kudela and others admit, but they hope the study will eventually help them develop a computer model that will predict blooms before they have a chance to cause havoc in the marine environment.