What is the greenhouse effect?

We explain what the greenhouse effect is and the causes of this phenomenon. Its consequences and its relationship with global warming.

1. What is the greenhouse effect?

It is known as  greenhouse  to an atmospheric phenomenon that occurs when the thermal radiation (heat) of the surface of the Earth , which commonly is emitted into space, is in retained change by greenhouse gases (GHGs) present in the atmosphere due to air pollution . This causes an increase in the planetary temperature , since the heat does not escape, as in a greenhouse. From there comes the name of the effect.

The solar light that our planet receives every day warms its surface, including the waters of the ocean , providing an enormous amount of light and heat that allow life and inject the energy necessary for its different chemical and physical cycles.

However, part of that caloric energy is reirradiated outward at lower frequencies (infrared radiation), allowing some room for cooling and balance .

This process is interrupted or diminished when gases such as water vapor, carbon dioxide (CO2) , methane (CH4), nitrogen oxides (NxOy) and ozone (O3), known therefore as gases, abound in the atmosphere. Greenhouse If there were none of these gases in the atmosphere, the average temperature of the planet would be -18 ° C and life would be impossible.

On the other hand, if these gases exceed the natural measure of their presence in the atmosphere, the heat accumulated on the planet will rise and alter the planet’s climate balance, accelerating or intensifying global warming .

2. Causes of the greenhouse effect

The registered margins of greenhouse gases in the atmosphere at the end of the 20th century, have a direct relationship with the start of human industrial activities, which have thrown so many gases of this nature into the atmosphere, that the CO2 concentration index in the atmosphere has increased by 40% since 1750 (from 280ppm to 400ppm).

The addition of carbon to the atmosphere by our species exceeds the current capabilities of the planet to recycle it (through the Carbon Cycle ), since it comes from almost three centuries of massive combustion of fossil hydrocarbons (coal, oil , natural gas) and other similar economic activities, such as mass livestock or deforestation (which reduces the amount of plant life available to recycle environmental CO2).

It should also be considered that many of the gases released into the atmosphere by human industry are long-term , that is, they are not easy or fast to decompose to recover the chemical balance of the atmosphere.

3. Consequences of the greenhouse effect

As said before, the greenhouse effect is necessary for life on the planet, since without it the heat would be fired into space . The problem is, on the other hand, in the disproportionate increase in the gases responsible for this effect, which has a direct consequence: the gradual but sustained increase in world temperature. This is known as global warming and has a series of consequences:

• Climate change . The rise in global temperature leads to the alteration of hydrological cycles and tides, which upsets the way in which our planet distributes heat and cools itself. Thus, climates are turned into extreme versions of themselves: longer and harsher winters, more stifling and dry summers. When it rains, it floods; when not, there is drought.
• Melting of the poles . The ice caps at the poles serve as a natural refrigerator on the planet, and also retain a significant percentage of fresh water in the solid state . The temperature increase gradually reduces them, thus generating an acceleration in the heating, because there is less ice to counteract it and so on. This, moreover, implies that the level of the seas increases: fresh water will raise the coastline of the continents and many cities can be underwater.
• Generation of new deserts . Climate change so violent does not give a chance for life to adapt to new temperature conditions, which leads to the generation of new deserts or the lengthening of existing ones.
• Climatic disasters . Seasons of longer and more intense hurricanes, tropical storms with more rain than usual and other similar phenomena are a consequence of global climate imbalance.

4. Greenhouse effect and global warming

The link between the prolonged emission of greenhouse gases and global warming is proven by scientists, despite the fact that there was a lot of skimming and much debate about it.

Some sectors, especially those that would have to make greater efforts to reduce CO2 emissions into the atmosphere (the industrial sectors of the more developed countries, precisely), insisted that it was a natural cycle of warming , product of the end of An ice age

And while this is still true in terms of geological time, neither does the increase in the level of greenhouse gases in the atmosphere pick up and accelerate greatly since the Industrial Revolution of the eighteenth century.