Six years ago, a huge part of the Pacific Ocean near North America quickly warmed, reaching temperatures more than 5 degrees Fahrenheit above normal. Nicknamed “the blob,” it persisted for two years, with devastating impacts on marine life, including sea lions and salmon. The blob was a marine heat wave, the oceanic equivalent of a deadly summer atmospheric one. It was far from a solitary event: Tens of thousands have occurred in the past four decades, although most are far smaller and last for days rather than years. The largest and longest ones have occurred with increasing frequency over time. On Thursday, scientists revealed the culprit. Climate change, they said, is making severe marine heat waves much more likely. The study, published in the journal Science , looked at the blob and six other large events around the world, including one in the Northwest Atlantic in […]