Ocean Heatwaves Last Three Times Longer Now: Is the Climate Crisis to Blame?

Ocean heatwaves now last three times longer now due to climate crisis, supercharging deadly storms and destroying important ecosystems, according to a study published in the journal Proceedings of the National Academy of Sciences.

As reported by The Guardian, scientists found that burning fossil fuels caused half of the marine heatwaves since 2000 — heatwaves that likely would not have occurred without human influence. The researchers noted that the heatwaves have become not only more frequent but also more intense, averaging 1 degree Celsius warmer globally, with some regions experiencing much higher temperatures.

The study is the first comprehensive assessment of the impact of the climate crisis on heatwaves in the world’s oceans, reported The Guardian.

Increased Duration of Ocean Heatwaves

“In the Mediterranean, we have some marine heatwaves that are 5C hotter,” Marta Marcos, lead author of the study at Mediterranean Institute for Advanced Studies in Mallorca, Spain told The Guardian. “It’s horrible when you go swimming. It looks like soup,” Marcos added.

Speaking about the underwater ecosystems such as sea grass meadows, Marcos shared that the warmer oceans provide more energy to the strong storms that affect people at the coast and inland.

The study also highlighted that there were about 15 days of extreme heat a year at the ocean surface in the 1940s, however, the figure rose to a global average of about 50 days a year. Some regions, including the Indian Ocean, the tropical Atlantic and the western Pacific have 80 heatwave days a year, i.e., one day in every five.

As the seas in the tropics are already warm, the extra heat increases the duration of heatwaves. In cooler seas, the extra heat also increase their intensity, as seen in the Mediterranean Sea and the North Sea.

Xiangbo Feng, part of the study team at the University of Reading, told The Guardian, “As global temperatures continue to rise, marine heatwaves will become even more common and severe. Human activities are fundamentally changing our oceans. Urgent climate action is needed to protect marine environments.”