The Atlantic Ocean Is Cooling Rapidly. What’s Really Going On?

The Atlantic Ocean has been experiencing an unexpected and rapid drop in surface temperatures, leaving scientists searching for answers. Over the past year, ocean temperatures across the globe reached new record highs. However, in the last few months, the situation has changed dramatically.

According to the National Oceanic and Atmospheric Administration (NOAA), the Atlantic's sea surface temperatures have been cooling since May. The data shows that the Atlantic is now a degree or two Fahrenheit colder than usual for this time of year.

Typically, the Atlantic's temperatures are expected to rise during this period, influenced by both human-caused climate change and a complex weather pattern known as El Niño. El Niño refers to a warming of the ocean surface or above-average temperatures in the ocean.

Since March 2023, the Atlantic Ocean has been setting new heat records, partly due to an especially strong El Niño. However, it now seems that this pattern is shifting, with the Atlantic potentially transitioning into its counterpart, La Niña, where ocean temperatures become unusually cold.

The shift from El Niño to La Niña is puzzling experts, as both patterns are influenced by various factors like trade winds, solar heating, and rainfall, making them difficult to predict.

"We've gone through the list of possible mechanisms, and nothing checks the box so far," said Frans Philip Tuchen, a postdoctoral student at the University of Miami, in an interview with New Scientist.

The NOAA has also expressed concern about the environmental impact of these changes. A transition to La Niña could influence rainfall in nearby continents and increase the likelihood of hurricanes near the Cape Verde islands.

Michael McPhaden at NOAA noted that this shift might affect ocean cycles globally. The Atlantic's cooling could delay the Pacific Ocean's transition into La Niña in what he described as a "tug of war" between the two oceans.