BBC News reports:

The oceans have hit their hottest ever recorded temperature as they soak up warmth from climate change, with dire implications for our planet’s health.

The average daily global sea surface temperature beat a 2016 record this week, according to the EU’s climate change service Copernicus.

It reached 20.96C (69.73F) – far above the average for this time of year.

Oceans are a vital climate regulator. They soak up heat, produce half Earth’s oxygen and drive weather patterns.

Warmer waters have less ability to absorb carbon dioxide, meaning more of that planet-warming gas will stay in the atmosphere. And it can also accelerate the melting of glaciers that flow into the ocean, leading to more sea level rise.

Hotter oceans and heatwaves disturb marine species like fish and whales as they move in search of cooler waters, upsetting the food chain. Experts warn that fish stocks could be affected.

Some predatory animals including sharks can become aggressive as they get confused in hotter temperatures.

“The water feels like a bath when you jump in,” says Dr Kathryn Lesneski, who is monitoring a marine heatwave in the Gulf of Mexico for the National Oceanic and Atmospheric Administration. “There is widespread coral bleaching at shallow reefs in Florida and many corals have already died.”

“We are putting oceans under more stress than we have done at any point in history,” says Dr Matt Frost, from the Plymouth Marine Lab in the UK, referring to the fact pollution and overfishing also change the oceans. [Continue reading…]