There are two flavors of surprise: good and bad. Winning the lottery? Good. Extreme heat waves cooking the oceans with more regularity, ruining fisheries that millions of people rely on? Decidedly bad.

Yet that’s our present predicament, one that’s likely to get worse as the oceans heat up even further. A new study released in the Proceedings of the National Academy of Sciences on Monday shows that climate change is already pushing large portions of the oceans outside their normal bounds, resulting in what the authors call “surprise” conditions that can wreak havoc on fisheries and the livelihoods associated with them. Climate change could further push ecosystems outside their limits, forcing the people who rely on them to adapt or suffer the consequences.

To undertake their study, researchers dug into annual temperature data for 65 large marine ecosystems collected since 1900…