Earth in hot water? Worries over sudden ocean warming spike

The world's oceans are suddenly considerably hotter than just a month or two ago and well above record levels. Scientists are trying to figure out why, and whether it forecasts an upcoming surge in atmospheric warming. One big explanation for the warming surface water could be a brewing El Nino, which heats temperatures naturally, on top of human-caused global warming. But some scientists say these latest readings could be more than just that. There's ever-increasing heat in ocean depths. And the world is rebounding from three years of a bit of cooling from La Nina. If an El Nino does appear as forecast, then researchers say the record-breaking heat the oceans are showing now is just the beginning.