The Earth

What is the greenhouse effect?

What is the greenhouse effect?

The greenhouse effect is the process by which the atmosphere of a planet lets solar radiation from the Sun pass, but instead, prevents or hinders the exit of thermal energy from the planet.

It is called the greenhouse effect because of the similarity with the operation of the greenhouses. These systems are capable of retaining the heat inside. The difference is that the greenhouse uses glass and not gases from the atmosphere to retain heat.

When we talk about the greenhouse effect, we practically always refer to the effect produced on planet Earth. However, it also occurs similarly to other planets like Venus and Mars.

Human activities and the main non-renewable energy sources have caused an excessive increase in the greenhouse effect. One of the advantages of renewable energy such as solar energy is that they do not emit gases. Clean energy is a good alternative to counteract these effects.

What does the greenhouse effect consist of?

When the solar radiation that reaches the Earth's atmosphere part of this radiation is reflected as if the surface of the earth were a mirror. Another part is absorbed and enters the atmosphere.

Most of the radiation that has managed to enter the atmosphere reaches the Earth's surface. This causes the surface to heat up. Then some of this heat is released in the form of radiation, but at wavelengths longer than that of the original solar radiation.

Of the infrared radiation emitted by the Earth's surface, only a significant part will get back through the atmosphere and out into space. About 90%. The rest heats the gases in the atmosphere and their heat energy stays there. The planet is enveloped by a set of hot gases that contribute to heating it.

The atmosphere has the characteristic that it absorbs outgoing infrared radiation more easily than visible radiation received from the Sun. That is what makes Earth warmer than it would be without an atmosphere.

This event is what causes planet Earth to reach temperatures compatible with life. The greenhouse effect is therefore a natural phenomenon of the atmosphere. If heat were not retained in the atmosphere, Earth would freeze.

Why is the greenhouse effect a problem?

The greenhouse effect is not a problem for life on Earth. Actually, it is essential to retain solar heat and prevent it from freezing. The problem appears when this natural effect is enhanced by man's action.

By increasing this effect through other types of gases, the Earth's temperature rises and negatively affects the species that live on it. For example carbon dioxide or nitrogen oxide.

It is what is called global warming and one of the causes of climate change.

The burning of fossil fuels or the burning of a forest implies the emission of carbon dioxide. If the concentration of CO2 in the atmosphere increases, the greenhouse effect increases. 

Popular opinion began to worry about it in the late twentieth century.

Consequences of global warming

What is the greenhouse effect?Global warming would have major effects on life as it develops. Within the scientific community there is no consensus on the exact consequences. Even so, the most pessimistic theses list the following consequences:

  • Desertification and droughts, which cause hunger pandemics.

  • Deforestation, which further increases change.

  • Melting of Antarctic ice in the polar ice caps, causing a rise in sea level. The rise in the level of the oceans would cause the flooding of coastal cities.

  • Ecosystem destruction.

  • It would alter climatic regions and ocean currents, with possible important consequences on human activities.

The effect is related to energy for two reasons:

  1. This effect precisely describes the flow of energy. Solar energy in the form of radiation enters the atmosphere and part of the one you want to escape is trapped.

  2. The way humans generate energy can enhance this effect.

There are two types of power generation: renewable and non-renewable.

Most of renewable energy involves burning fossil fuels. Usually coal, derived from petroleum and natural gas. Burning these fuels generates a large amount of gases that enhance this effect. They are called greenhouse gases.

It should be mentioned that nuclear energy exists within non-renewable energies. Atomic energy has many environmental drawbacks but does not generate this type of gas.

On the other hand, renewable energy does not generate gases. They are considered clean energy for this reason. Therefore, renewable sources are a good alternative to soften climate change.

What are the main greenhouse gases?

Those responsible for this effect on the atmosphere are greenhouse gases. We list them in order of importance.

  • Water vapor (H2O)

  • Carbon dioxide (CO2)

  • Ozone (O3)

  • Other gases in a smaller proportion.

    • Methane (CH4)

    • Nitrous oxide (N2O)

    • Sulfur hexafluoride (SF6)

    • CFC

What is the greenhouse effect?These gases have a strong capacity for absorbing heat energy in the infrared region of the spectrum.

One of the most relevant moments was during the industrial revolution. During this process, the consumption of fossil fuels increased exponentially. Consequently, the emission of gases also increased in the same proportion.

What is the Kyoto Protocol and what agreements were made?

The Kyoto protocol is an international agreement that tries to globally limit greenhouse gas emissions. The protocol arises from international concern about global warming that could increase uncontrolled emissions of these gases.

The agreements that were carried out in the Kyoto protocol in 1997 were:

  • The signatory industrialized countries undertake to reduce greenhouse gas emissions by 5% in the period from 2008 to 2012 compared to 1990.

  • Rich countries must reduce their gas emissions by between 25% and 40% by 2020, compared to 1990.

  • The long-term negotiation establishes that the increase in temperature must be below two degrees with respect to pre-industrial levels. This objective will be reviewed because it does not exceed 1.5 degrees.

  • Adaptation of the least industrialized countries to face the disasters related to climate change.

  • Industrialized countries should promote strategies to lower carbon emissions, and developing countries should limit emissions with appropriate national plans and actions.

  • Action plans must be submitted every two years to an international control and verification system, although they must be done in a way that is non-instructive, not punishable and respectful.

  • Industrialized countries must provide aid of $ 30 billion in three years, until 2012 and mobilize resources up to $ 100,000 annually in 2020.

  • Aid will be channeled through a fund with 24 members and in which 12 will come from rich countries and others.


The greenhouse effect is the mechanism by which the Earth's heat cannot escape. Part of the solar radiation that reaches our planet is absorbed and another part bounces back into space. However, various elements present in the atmosphere prevent it from escaping.

This effect occurs naturally and is necessary for life. However, the human presence has enhanced it too much. The main consequence is a climate change due to global warming of the planet.

Publication Date: July 25, 2016
Last Revision: May 29, 2020