According to Reuters, it is estimated that the oceans are warming faster in comparison to the past, setting a new record on temperature in 2018, resulting to damaging marine life. Measurements, run by an international network of 3.900 floats that are deployed in the oceans since 2000, revealed an increased warming since 1971, than what it was calculated by the UN assessment of climate change in 2013.
Specifically, as written by the authors in China and the US in the journal of Science of ocean...
https://safety4sea.com/oceans-warm-faster-than-expected-reach-heat-record-in-2018/