All you need to know about the five-year low

Weather of Arabia - The first thing that comes to our mind when mentioning a depression is cold winter weather, heavy clothing, heavy rain or even snow, but it is not necessary that every depression will bring rain and cold weather, there are types of depressions, including frontal depressions that bring rain and the usual winter weather The other type is thermal depressions, from which a type of depression is branched, known as the five-point depression, which brings several weather phenomena, including high temperatures.

What is the Khamasini depression and how is it formed?

Before we enter into how the five-year depressions are formed and defined, we must know how it happens that there is a depression even though the temperatures are high, we must know that depression is a term that is not related to temperature, as depression is a term that expresses a decrease in the values of atmospheric pressure in an area certain on the Earth's surface from the surrounding atmospheric pressure values.

As for the definition of the five-year depression, it is a type of thermal depression, which is active in the spring, and the five-year depressions usually arise in the Algerian desert east of the Atlas Mountains, but the locations of their formation differ, and at some time the five-year depressions can form in the Libyan territories.

This type of depression is formed as a result of the high heating of the land (the surface of the earth). In the spring, temperatures begin to rise in the north of the African continent, as the surface of the earth heats up. Because of the difference in specific temperature between land and water, the water surface of the Mediterranean remains cold, and the land becomes warmer. Thus, the air on land begins to expand, its weight decreases, and the atmospheric pressure decreases, announcing the birth of a five-year depression in the Sahara desert.

What are the paths covered by the Khamaseen depressions?

After the Khamaseen depressions are formed, they have three paths that they can take. The first path is that these depressions continue to move towards northern Libya, continuing their way directly towards the Levant, and here their effects are very clear on the Levant.

The second path is that the Khamaseen depressions continue to move within the Sahara desert until they reach the Egyptian lands and later complete their way towards the Kingdom of Saudi Arabia, and the Levant will be indirectly affected by it.

The third path is for the five-year depressions to liberate from the African continent towards the south of the European continent and Turkey, and in this case it attracts a cold air mass, and the five-year depressions then turn from thermal to rainy and cold frontal depressions that affect the places they pass through.

What is the period of activity of the five-year depressions, and why was it called by this name?

This type of depression has been called the "Khamsiniya", because the period of its activity extends from the beginning of the spring solstice with the 21st of March of each year, until the 10th of May of each year. At that time, in the "semi-fifty" depressions.

What are the five depressions associated with?

The five-year depressions are usually accompanied at the forefront by the rush of an air mass with much warmer temperatures than usual, and some of the rushing air masses at the front of the five-year depressions are sometimes very hot and cause heat waves to occur in some countries of North Africa, the Levant and the Arabian Peninsula.

And blowing with the Khamaseen depressions, winds known as the Khamaseen winds, which are mostly southwesterly winds, are sometimes dry and hot, come from the African Sahara and are loaded with dust and raised soil, and move quickly towards the eastern Mediterranean regions such as Egypt, the Levant and the Arabian Peninsula, It pushes with it waves of dust coming from the desert, and sometimes the winds are strong enough to cause sand storms that move in the front of the Khamseen depressions.

At the forefront of the quinquennial depressions, the quinquennial weather conditions prevail, represented by dry, warm (or hot) and dusty weather.

However, the five-year depression soon recedes, followed by an air mass with lower temperatures, which leads to a sharp drop in temperatures in a period of time that may not exceed 24 hours sometimes!.

Can the five-year depressions be accompanied by rain?

The answer is yes. Sometimes the five-year depressions coincide with the approach of a cold air mass in the upper layers of the atmosphere, and at that time a convergence occurs between warm, dry air currents in the lower layers of the atmosphere with cold ones in the upper layers of the atmosphere, and results in a state of atmospheric instability that leads to thunderstorms It is often muddy as a result of the mixing of rain with dust from the five-year depressions.

In other cases, the Khamseen depressions coincide with the spread of large amounts of clouds at medium and high altitudes, which at some time result in local mud showers of rain in limited geographical ranges.

The damages of the five depressions

1. Among the damages that may affect humans as a result of dusty weather: chest allergies, lung and bronchial infections, and nasal and throat congestion if a person is exposed to wind and dust, in addition to their effect on the range of vision, inflammation of the eyes, and spring ophthalmia.

2. From the damage that may affect plants: leaves tearing and pollen atrophy, and may cause flowers and fruits to fall as a result of the wind, and increase the risk of infection with the red spider.

3. Sandy winds may cause damage to cars: especially if the car is driven in the opposite direction of the wind, which leads to scratches in the paint, windshield and headlight covers, and the air filter in the car may become clogged with repeated driving in sandstorms.