Greenhouse effect: what it is, characteristics and consequences

We explain what the greenhouse effect is and what its causes and consequences are. Also, its characteristics and possible solutions.

The greenhouse effect is a natural phenomenon that makes life on Earth possible.

What is the greenhouse effect?

The greenhouse effect is a natural process that occurs in the Earth’s atmosphere.where certain gases (such as carbon dioxide, methane, and water vapor) trap heat from the Sun and retain it near the surface.

This effect, similar to that produced by greenhouses in agriculture, allows to maintain the Earth’s temperature at a level suitable for the development of life.

However, in recent decades human activity has produced a significant increase in greenhouse gases in the atmosphereIt is believed that this excess of greenhouse gases is what is causing the increase in the average temperature of the atmosphere, which in turn produces serious consequences for climate dynamics, biodiversity and the quality of life on the planet.

What is the atmosphere for?

In agriculture, a greenhouse is a construction that allows the heat from the sun’s rays to be retained.

A greenhouse is a construction that allows the heat of the Sun to enter but, due to the absence of ventilation, does not let it out. Greenhouses are used to grow vegetables that require high levels of temperature and humidity.

The Earth’s atmosphere produces this same effect since allows the sun’s rays to reach the earth’s surface, but then partially retains its heat. Thanks to the fact that the atmosphere works like a greenhouse, life that requires a certain minimum temperature to survive can develop on the Earth’s surface.

If greenhouse gases did not retain that heat, the average temperature of the planet is believed to be 30 degrees lower than it is today.

Causes of the increase in the greenhouse effect

Deforestation causes CO2 to remain on Earth longer.

The greenhouse effect produced by human activity is caused by the excess of greenhouse gases (mainly carbon dioxide, methane and water vapor) in the atmosphere.

Burning fossil fuels, such as oil, gas, and coal, releases carbon dioxide into the atmosphere. The use of fossil fuels for energy production, transportation and industry are the main causes of the emission of this type of gases.

For this reason, greenhouse gases in the atmosphere increased rapidly from the mid-18th century, when the Second Industrial Revolution began to accelerate and intensify.

The increase in deforestation worldwide also explains the increase in the concentration of greenhouse gases in the atmosphere. Trees capture carbon dioxide and convert it into oxygen through photosynthesis.The decrease in forested area worldwide reduces carbon dioxide uptake, causing this gas to remain in the atmosphere for longer.

Other greenhouse gases have also increased in concentration in recent years. Methane, for example, is released by livestock farming through animal faeces and by poor waste management, which, when decomposing, also releases this gas that accumulates in the atmosphere.

Consequences of the increase in the greenhouse effect

The melting of the poles affects the ecological balance of the planet.

The direct consequence of the increase in the greenhouse effect is global climate change, which in turn generates a series of ecological and environmental consequences. Among the most significant, the following stand out:

• Changes in precipitation patterns. Climate change has altered rainfall dynamics globally, leading to more frequent and intense floods and droughts in different regions of the world.
• Changes in ecosystems. Climate change has produced severe ecological changes that include the loss of biodiversity and the extinction of many species.
• Rising ocean temperatures. Climate change affects marine life and aquatic ecosystems. It also favors an increase in the frequency and intensity of extreme climate phenomena that feed on warm water, such as hurricanes and tropical storms.
• Deterioration of human health. Climate change affects human health through air pollution, exposure to high temperatures and heat waves, lack of water, floods, and the transmission of diseases, among other causes.

Greenhouse gases

Carbon dioxide is mainly emitted by the burning of fossil fuels.

The main greenhouse gas is water vapor.The second most important is carbon dioxide, despite being a gas that makes up a tiny percentage of the atmosphere (only 0.035%, i.e. for every million particles only 350 are carbon dioxide). Any variation in the amount of this gas in the atmosphere has a profound impact on the greenhouse effect, since a small added amount can produce significant effects.

He Intergovernmental Panel on Climate Change (IPCC) estimates that approximately 50% of carbon dioxide emissions will remain in the atmosphere for several decades, and about 20% will remain for several thousand years. These percentages may vary depending on atmospheric conditions and the way in which these emissions are emitted and absorbed.

Earth’s energy balance

The sum of solar energy arriving from the Sun and the energy radiated by the Earth constitutes the planet’s energy balance, and must be balanced to maintain the average temperature at stable values.

How much radiation does the Earth receive?

Solar energy reaches the Earth in the form of light and heat. The energy that reaches the Sun is 341 W per square meter and is short wave. Part of this energy is retained by the atmosphere (157 Watts) and another part reaches the Earth’s surface (184 Watts).

How much radiation does the Earth emit?

The Earth not only receives but also emits heat. The heat radiated by the Earth’s surface annually is 396 W per square meter and is infrared radiation.

This heat is also partially absorbed by greenhouse gases and reemitted to the Earth’s surface.

reflected radiation

Light colored objects like snow reflect the most energy.

Both the Earth’s surface and the atmosphere reflect part of the energy received by the Sun, that is, this energy does not remain in the atmosphere but is dispersed outside it. The amount of energy reflected together by the Earth’s surface and by the atmosphere is 102 W per square metre, i.e. less than a third of the radiation received from the Sun.

The objects that reflect energy the most are those of light colors, such as snow or clouds. Darker objects, such as forests, absorb it.

Some of the infrared radiation emitted by the Earth’s surface is not absorbed by greenhouse gases, so it passes through the atmosphere and disperses into space.

How to reduce the effects of climate change?

Many large cities seek to replace fossil fuels with clean energy.

To reduce the emission of greenhouse gases and, consequently, reduce the effects of climate change, Several countries seek to replace fossil fuels with cleaner energy sources, such as solar, wind or geothermal energy. Many companies also implement more efficient production and consumption measures in terms of energy use.

In addition, in large cities, efforts are being made to reduce pollution caused by means of transport by promoting the use of public transport, electric vehicles and bicycles.

International agreements on the greenhouse effect

Several countries signed agreements to work together on climate change. Some of the most important were:

• Kyoto Protocol (1997). It was the first international agreement on climate change. This treaty required industrialized countries to reduce their greenhouse gas emissions below 1990 levels.
• Paris Agreement (2015). It was an agreement in which all countries committed to fighting to limit the increase in global temperature to less than 2ºC above pre-industrial temperatures. It was agreed that countries would commit to reducing their greenhouse gas emissions every five years, and a fund was established to help the countries most vulnerable to climate change.

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References

• Benavidez Ballesteros, H. and León Aristizábal, G. (2007). Technical information on greenhouse gases and climate change. IDEAM – METEO, 008.
• Goudie, A. (2009). Human impact on climate: past, present and futureProgress in Physical Geography, p. 252-258.
• Hernandez, Y (2020). Climate change: causes and consequences. Renovat Magazine, 4th Sena