The past decade has seen the Atlantic Ocean see its hottest temperatures in almost three thousand years.
This is according to a new study that found recent spikes in temperature go well beyond what is expected from natural patterns.
Rising ocean temperatures are bad news for a lot of marine life.
Hotter oceans also lead to worrying weather, including increasingly-severe hurricanes.
The Atlantic Ocean flows between the UK and the US and all the way down to Africa.
It’s the second-largest ocean in the world.
Scientists were able to track the Atlantic’s changing temperatures back to around 2,900 years ago.
They did this by looking at ice, thermometer data and sediment cores in the Canadian Arctic.
These cores date back thousands of years and visibly change according to temperature.
The sediments were able to show regular patterns of ocean temperature changes as well as a worrying increase in temperature in recent years.
Causes of ocean warming were not pinpointed in the study but climate change is thought to be responsible for warming temperatures all over the world.
The warming temperatures could lead to storms, mass extinction for many species and the study suggests the problem will only get worse.
The researchers were from the University of Massachusetts Amherst and the University of Quebec.
This study was been published in the journal Proceedings of the National Academy of Sciences.