El Niño Changes the Salinity of the Red Sea.. The Impact Peaks After Months

Listen to the article, the audio text is automatically generated by a machine system.

Researchers at King Abdullah University of Science and Technology (KAUST) have revealed that the El Niño and Southern Oscillation (ENSO), which originates thousands of kilometers away in the tropical region of the Pacific Ocean, can cause significant changes in the salinity of the surface waters of the Red Sea from year to year.

The study also indicated that this atmospheric correlation is strongest during the month of October, while the salinity changes associated with it reach their peak levels in May of the following year.

As the climatic cycle oscillates between the warm "El Niño" phase and the cold "La Niña" phase, its effects can extend to areas far from the Pacific Ocean, through changes in atmospheric pressure patterns and winds, which affect the weather and ocean conditions in those regions.

For his part, Professor Ibrahim Hattit, a professor of Earth Systems Engineering and Sciences at KAUST who led the research, said: "Studying these links is particularly important at the moment, as we are currently witnessing an unusually strong El Niño phenomenon, which is expected to intensify until the end of 2026. Our results help us understand how the most severe climatic events in the Pacific can manifest as more pronounced changes in the region."

The study, published in the scientific journal "JGR Oceans" specialized in ocean research, identified two pathways that transmit this effect through the atmosphere; one is related to changes in atmospheric pressure over the Indian Ocean, while the other is linked to changes in atmospheric pressure over the Mediterranean region. These changes collectively lead to modifications in wind patterns over the Red Sea.

Changes in winds affect the salinity of the Red Sea in two ways; they influence the amount of less saline water entering it from the Gulf of Aden through the Bab el Mandeb Strait, and they also affect evaporation rates differently between the northern and southern parts of the sea.

To study these links, the team analyzed high-resolution computer simulation results of water movement in the Red Sea, covering the period from 1997 to 2018. The model tracked monthly changes in surface water salinity, evaporation, and ocean currents, while the researchers validated its accuracy extensively by comparing its results with observational data from the Red Sea.

For his part, research scientist at KAUST and the lead author of the study, Junchuan Sun, said: "Understanding the distant climatic factors affecting the Red Sea gives us a much clearer picture of its water movement and the changes occurring within it. Analyzing these links, month by month, has provided us with a better understanding of how changes originating in the Pacific Ocean are transmitted through the atmosphere, reaching their impact on the Red Sea."

The Red Sea is one of the saltiest seas in the world. Salinity plays an important role in the formation, mixing, and circulation of water layers, and therefore changes in salinity can lead to alterations in the physical conditions that marine organisms adapted to the highly saline environment of the Red Sea experience.

Understanding these changes can also contribute to supporting efforts to protect coral reefs in the Red Sea, and enhance environmental management and planning in marine areas, alongside broader efforts to adapt to climate change.