Arabian Weather: The La Nina phenomenon is in a remarkable development, and this is its impact on the Arab world | Weather Arabia

Weather Arabia The latest statistical forecasts for Arab weather still indicate an expected return of the La Niña phenomenon in the coming months, God willing.

What is the La Niña phenomenon?

The La Niña phenomenon is initially defined as a decrease in surface water temperatures in the tropical region of the Pacific Ocean from their general averages of more than 0.5 ° C and over a period of more than 3 consecutive months.

The trade winds blow from east to west in the equatorial region of the Pacific Ocean due to the rotation of the Earth on itself, and from there begins the story of La Niña. The humidity forms a system of low atmospheric pressure, then the air moves again along the upper part of the troposphere towards the eastern Pacific Ocean, forming a ring, then this cold air converges from top to bottom along from the eastern coast of the Pacific Ocean forming a region of high pressure, then the wind moves from the high pressure system to the low level to complete this cycle.

The end result is warmer surface water in the west and cooler surface water in the east. Peru and South America, which suffer from the cold waters adjacent to it.

So how does this affect the weather in the Arab world?

The effect of the La Niña phenomenon is not limited to the vertical movement of air at the equator, but its effect is evident on the horizontal movement, where the ascending air from the equatorial region of the Pacific Ocean moves away. from the equator to higher latitudes. to the north and south, move the warm tropical air towards the tropics Cancer and Capricorn to descend towards the earth’s surface and return again towards the equator and this is called the Hadley rotation.

The subtropical jet stream is formed as a result of the confluence of the high altitude winds of the Hadley cycle with the Ferrel cycle, which means that the La Niña phenomenon indirectly affects the subtropical jet stream and atmospheric heights that occur at latitudes close to 30 degrees. the north, like the subtropical high. The phenomenon of La Niña towards the Indian Ocean, as it indirectly leads to a decrease in the temperature of surface water in the western part of the Indian Ocean and the Arabian Sea, which leads to a decrease in the amount of water vapor rushing to the atmosphere of the Arabian Peninsula after the will of God.

Statistically, the La Niña phenomenon

The La Niña phenomenon is above all a statistical phenomenon, i.e. it depends on temperature anomalies for a certain period of time (since the start of climate records, i.e. since 1960 after JC), and the La Niña phenomenon is statistically associated with less than average rainy seasons in the Arab Mashrek, in stark contrast in regions of the Maghreb with increased precipitation, lower than normal temperatures and increased risks of floods and torrential rains in the Maghreb regions.

“Misconceptions about El Nino” is the title of a study published by the World Agency NOAA, expressing that El Nino and its counterpart La Niña are an atmospheric variable that contributes among dozens of other variables to weather, including perhaps more important is the surface temperature of the waters of the northern half of the Atlantic Ocean (MASTER) and the movement of transverse air currents in the stratosphere (QBO), and many other meteorological factors, i.e. meteorological conditions are not exclusive and result from a particular meteorological phenomenon.