Record marine heatwaves may signal a permanent shift in the oceans

The extreme marine heat recorded since 2023 could announce the start of a regime change in the world’s oceans which constitutes a serious threat to life on earth, scientists warned.

Record marine heat waves emerged in the oceans of the North Atlantic and Pacific in 2023 and were unprecedented in their gravity, their endurance and their geographic scale, with much more than a year.

Heat waves have helped push the temperatures of the sea surface to the world’s registration levels in 2023 and 2024, resulting in extreme heat and dangerous time on earth and contributing to the two years consecutively as the warmest ever recorded.

“We have had a gradual warming of our oceans in the last 40 to 50 years, but 2023 has been a year in small groups, with large-scale sea waves affecting so many different sites,” explains Matthew England at the University of New South Wales in Australia.

Sea surface temperatures in the world are always at almost record levels, and currently the Mediterranean Sea is in the grip of a marine heat wave with water temperatures up to 5 ° C (9 ° F) above normal for the period of the year.

Some researchers fear that the oceans of the world have passed to a newer new state, threatening our ability to predict with precision both short -term weather conditions, such as hurricanes and long -term climatic work quarters.

To find out more about what’s going on, Zhenzhong Zeng at the University of the South Science and Technology in China has undertaken colleagues to identify the engines of marine heat waves 2023 in the world, analyzing the movement of heat, wind and currents in the oceans. A reduced cloud cover, which increases the quantity of solar radiation striking water, turned out to be a key influence, alongside the lower winds and the appearance of an El Niño warming in the Pacific Ocean.

Given the duration of the heat, which started seriously in 2023 and continues today in certain regions, Zeng thinks that it is the beginning of a “new normal” for the oceans of the world. He says that emerging data indicates that heat in the oceans accumulates exponentially, a trend that would challenge the predictions of the climate model.

The temperatures of persistent water will have a devastating effect on marine life, degenerating the threat of the collapse of coral reefs and triggering mass death and a migration of marine life. It would also accelerate heating on earth, leading to droughts, heat waves, forest fires and more severe and widespread storms.

Zeng says he is “very frightened” by this potential change in regime in the oceans. “I think almost all the projections of the earthly system model are wrong,” he says.

But some researchers think that it is still far too early to warn of a fundamental change in the dynamics of the oceans. Neil Holbrook at the University of Tasmania in Australia says that there are not yet “clear evidence” to support the warnings that we have reached a tilting point, in particular since there is only a few years of data to assess. “We don’t know what’s going to happen next year, and that [ocean temperatures] Could go back to something that is much more, let’s say, normal, ”he says.

However, Holbrook stressed that less that greenhouse gas emissions are quickly reduced, “sea heat waves around the world will continue to increase intensity and duration, and potentially at rates faster than various marine species can adapt”.