What is a heat dome

Representation of a heat dome

Answer the question what is a heat dome requires that, first, we situate ourselves in the context. He climate change that we have been suffering is causing, among other meteorological phenomena, a general rise in temperatures.

In fact in Spain It has become common to see summer days in which temperatures exceed forty-five degrees Celsius. And in other areas of the planet that are not very conducive to heat as Greenland temperatures have been recorded twenty to thirty degrees above average. But, in addition, the changes in the climate have caused us to become familiar with concepts that until now we had never heard of. One of them is the heat dome that we are going to explain below.

What is the heat dome?


Drought, one of the consequences of the heat dome

These words refer to the atmospheric phenomenon consisting of a mass of dry and hot air settling over an area for a long period of time. With this, it becomes stationary, that is, it does not move and creates a kind of cupola or dome that maintains heat on the surface of that territory.

Actually, it is not a new circumstance. It has always happened, what happens is that, in recent years, it has been repeated too frequently. And, in addition, it causes higher temperatures than before. In the words of the Mexican specialist Alberto Hernandez Unzon, is like what happens in "an express pot".

This is a very simple comparison, but accurate. The dome or dome that is formed acts as the lid of that appliance, conserving the heat on the surface. And, in turn, sun it further heats the already warm area, causing temperatures to rise a lot.

We could also compare this atmospheric phenomenon with a big bell placed on the earth's surface. It would prevent both the entry of fresh air and the exit of hot air, causing the latter to remain inside. If we add to this the arrival of solar rays that heat the environment even more, we have very high temperatures.

What are the causes?

heat wave in europe

Graphic reproduction of a heat wave in Europe

Regarding why the heat dome occurs, we must explain that there are general causes and other more specific ones. Among the first, the global warming is the most important. But the combination of high atmospheric pressures y variations in wind circulation patterns.

Regarding the more specific reasons for this atmospheric phenomenon, experts link its existence to ocean temperatures. A priori, it is possible that you will not find a relationship between the heat of the ocean water and the warmth of the graduations on land, but it does and we are going to explain it to you.

In this chain phenomenon. It all starts when seawater evaporates for heat and, in turn, warms the air. This is what happens, on a scale, when you heat water in a pot without a lid. When you put your hand on it, you will see that the steam rises and causes heat. But, returning to the case at hand, the warm air goes deep into the earth and is trapped by a high pressure system that pushes him down. Thus, it results in warmer surface temperatures.

To finish explaining this phenomenon, we must briefly clarify what a high pressure system is. This is what we popularly call anticyclone. When this occurs, the heavier air descends on our planet and, in turn, drives down and keeps fixed the heat that has entered from the sea.

When a high pressure system occurs, the resulting time is stable, with few clouds and almost no wind. This, likewise, enhances the heat caused by the dome. On the contrary, a system of low pressures or storm disperses the air causing it to exert less force, that is, less pressure, on the surface of the earth.

Consequences of the heat dome


A thermometer reading forty-two degrees Celsius

Once we have put you in context and we have clarified what a heat dome is, it is important that we explain to you what the consequences of this phenomenon may be. As you will have deduced, It is dangerous for people's health. Very high temperatures can cause dehydration and heat stroke.

Likewise, it harms the most vulnerable, such as children and the elderly, and the sick. For example, those who suffer from respiratory diseases can worsen in the heat. Even this atmospheric phenomenon has detrimental effects on food. It is because severely affects agriculture. High temperatures and lack of rain cause droughts and loss of crops. This can cause shortages of edible products.

But the lack of water also has harmful effects on biodiversity. Given the lack of fresh water, the species are reduced significantly with the death of many of its specimens. In addition, high temperatures cause numerous forest fires that destroy forests, end their fauna and can even reach the towns. In short, the consequences of the heat dome are detrimental to humans, animals and the environment.

How long can this weather phenomenon last?

Forest fire

Forest fires are often due to a heat dome

Heat Domes do not have a set duration. In fact, they can last for days or weeks. And, as we told you, they are becoming more frequent and more extensive in time. However, most last for days until a low pressure front cools the environment.

Precisely, on these dates a dome will begin in Spain. The Meteorological Agency has issued notice that 44 degrees Celsius will be reached in some areas of the Iberian Peninsula. The highest will be recorded on Tuesday the eleventh in the Guadalquivir valley and in the southwest of the country, but they will also affect the southeast, the Balearic Islands and, in general, the entire Spanish territory. Therefore, we recommend that you be especially careful with the heat in the coming days.

In conclusion, we have explained to you what a heat dome and what are its causes and consequences. As for the former, it is related to the global warming, especially in what affects its intensity. Therefore, it is important to take all measures to correct the climate change that we have been suffering.

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