The phenomenon of baffling scientists ... ocean currents are accelerating, contrary to expectations

Little West

Contrary to what had been expected, a new scientific study revealed that oceanic currents have witnessed an acceleration during the past three decades.

The researchers attributed this to the increase in wind speeds over the surface of the oceans, especially in the tropics, due to climatic changes that scientists previously expected will slow these currents and may stop them altogether in the distant future.

The ocean currents are one of the main factors that affect the Earth's climate. They transfer heat from the tropics to the colder regions, thus providing a warmer atmosphere, especially in the winter season.

Scientific studies differed about the effect of climate changes on these oceanic arteries, and the results of many of them showed a slowing of the Jetstream stream north of the Atlantic Ocean.

It has been increasing since the nineties
But the results of the study - published by an international team of researchers from the United States, China and Australia in the Scientific Report on February 5 - indicate the opposite, as it appears that climate changes have led to the acceleration of ocean currents, especially in the tropics.

In this paper, "Shijian Hu" researcher of the Chinese Academy of Sciences and his colleagues studied in detail how ocean currents around the world have changed by collecting global network data to measure currents from the ocean surface to a depth of two thousand meters since 1959.

In addition, the researchers used another series of measurements in addition to 12 different digital simulations to determine the kinetic energy of the oceans and the resulting behavior.

The results showed that although there were no uniform trends in ocean currents before 1990, the situation changed after that.

All data records indicate a common upward trend. Beginning in 1990, the ocean kinetic energy increased by 15% compared to the average kinetic energy before the 1990s.

The researchers say that this acceleration can be observed in all large marine basins up to a depth of two thousand meters, which is a gradual increase from the surface to the depths. The greatest increase in velocity of currents was recorded in tropical ocean regions, where the kinetic energy of the oceans increased much more than that recorded in areas far from the equator.

Wind is a major driver
But why did ocean currents increase in motion? Could known natural fluctuations be behind this? It is known that some climatic phenomena such as the El Niño phenomenon or the phenomenon of inverse Pacific oscillation affect sea temperatures and ocean currents.

According to the scientists, these found changes cannot be explained by such natural fluctuations alone. "This trend has been much stronger than the natural change in the past two decades," scientists say.

So what is the cause of the acceleration of ocean currents? According to the researchers, the winds are the engine of these changes. The results of the analysis of global weather data showed that wind speeds over the oceans have also increased significantly in recent decades.

As the wind accelerated, on average, by 1.9% in the decade. The researchers found a correlation between the increase in wind speeds over oceanic basins and the acceleration of ocean currents in them.

Scientists say it has become clear that previous assumptions suggesting that global warming is weakening the oceanic cycle are becoming incorrect.

Because even if high water temperatures and salinity change play an important role in the functioning of ocean currents, they do not appear to be the main factors influencing them. Instead, the effect of winds that drive water into the oceans faster prevails, enhancing the movement of ocean currents.