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The Greenhouse Effect


The Greenhouse Without Tomatoes: What Is The Greenhouse Effect And How Does It Cause Climate Change

  • The greenhouse effect is caused by our atmosphere
  • The greenhouse gases that are present in our atmosphere, such as water vapor, CO2, ozone and methane create a “shield” that traps the heat around our planet
  • Greenhouse effect is natural and helps sustain life on Earth
  • Human activity significantly adds to the greenhouse effect, by producing huge amounts of CO2 and methane
  • The increasing content of greenhouse gases leads to the increase of global temperatures on the planet
  • This global warming can damage life at seas and on land
  • People need to counteract these effects if they want the life on Earth to survive

A typical greenhouse  

Have you ever seen a greenhouse in a garden? They are usually made of plastic or glass. Sometimes, there is a source of heat and a lamp inside (for the autumn-winter months). And there are pots or other special arrangements where plants can grow. On the sunny days, the rays heat up the house through the transparent walls. But as the walls do not let the air through and there is no air exchange with the outside, all the heat stays inside. Pretty much like a car on a sunny day with all the windows shut. Plants living in a greenhouse are always warm. And if it is cold outside, they are protected from the cold wind and are nice and cozy inside at all times. By using greenhouses, people get strawberries and tomatoes even in winter.

Our Earth also has such a protective greenhouse. But it is made of gases, not some thick impenetrable material. Those gases are a part of our atmosphere. And though gases seem like a flimsy protection, when there is enough of them, they can trap heat, too.

The reports in the news use the term “greenhouse effect” as a curse. But in fact, the greenhouse effect made the life on Earth possible. It is true that our planet has a very favorable position – we are neither too far nor too near to the sun. Were the Earth too near to our personal star, the heat would have been unbearable. Were the Earth too far – it would have become an icicle. In either case, the Earth would not be able to have its own water, and without water there wouldn’t have been life as we know it.

But in fact, it is not only the convenient position of the Earth that made life possible. It is the fact that somewhere in course of the history of our planet, Earth could keep a portion of gases that flew from its surface in place. It began covering itself with an atmosphere. The atmosphere served several important purposes:

  • it partially shielded the planet from asteroids from space
  • it shielded the planet from aggressive sun radiation
  • it prevented the heat from escaping the planet fully

Without an atmosphere, Earth would be still too cold to live on. But the greenhouse gases in our atmosphere form a magic “gas mirror”. This is how this “mirror” works:

  1. The sun radiates heat. Its rays reach the atmosphere
  2. The atmospheric layer traps some rays and gets warmer. Another part of the sun rays gets through the gas layer and heats up the planet itself
  3. The soil and water surfaces reflect some of the heat back
  4. Some of the heat is kept under the atmosphere, and some heat escapes through

In some areas, it is still cold. But in others, the temperatures are far above zero. This way, there are always places where life can thrive.

Greenhouse effect diagram

There are certain type of gases that contribute to the greenhouse effect:

  • water vapor
  • carbon dioxide
  • methane
  • ozone

They are called greenhouse gases.

So far, so good. Due to greenhouse effect, our planet is not an icicle and can sustain life. But you must have heard that at present greenhouse effect is mentioned in connection to the term “climate change”. The same greenhouse effect that used to sustain life now becomes a danger to it. The climate is changing, the temperatures are either warmer or colder than before, and everything around us suffers. Why is that? The answer is simple – the human activity has reached such a scale that we are literally changing the climate on a whole planet.

Greenhouse Effect And Human Activity

In the last century, the concentration of carbon dioxide or CO2 in the atmosphere has significantly increased. The concentrations of methane have grown as well. The main reason for this process is human activity. We influence the concentration of greenhouse gases in several significant ways:

  • industrial activity – our plants and factories produce a lot of smoke that contain CO2
  • transport: trains, cars and ships also emit gases – CO2 included
  • cattle: cows and other species we are using as cattle produce a lot of methane while they are grazing. And they produce it in huge quantities, as farmers usually have big herds concentrated in one place
  • deforestation: in order to have fields to plant crops, to have place to build houses and to have wood to build things people have destroyed many acres of forests. And our trees are the main natural tool that helps lower the carbon dioxide content: they take up carbon dioxide and produce oxygen instead. As a result, oxygen concentration falls dawn and carbon dioxide content rises up
  • farming: farming some crops – rice, for instance, – also leads to methane release

As a result, the average global temperatures have increased considerably. And they will continue to increase in the future, unless we find ways to decrease the production of greenhouse gases. The present change in temperatures is already influencing life around us:

  • Damage to the sea life

First of all, as CO2 concentration increases, some CO2 is also absorbed by the seas and oceans. But too much CO2 can make the seawater acidic. Not all fish and other marine creatures can survive in such environment. Moreover, the increase in the temperatures in the seas leads, among other things to the bleaching of corals. They are losing their photosynthetic symbiotic bacteria and are dying out. Coral reefs are literal nurseries of sea life, and without them the diversity of various creatures of the seas would inevitably become lower. Do you want to lose slender corals, bright clownfish and other amazing creatures to the warming?

A bleached coral
  • Damage to the land life

The summer of 2018 was especially hot, wasn’t it? In many areas of Europe, there was hardly any rain for a month. The grass was low and the leaves on the trees became yellow too early. This meant too little food for the herbivorous species. The rivers also were slowly drying out – less water for everyone, and less fish for the predators. Animals unused to higher temperature had a harder time to survive, as well. Moreover, climate change also means colder winters – and in temperate regions it again means less food for the birds and animals, and problems with survival.

  • Damage to human health

Humans are also suffering from climate change. In the hot summers, the likelihood of overheating and having a stroke is quite high. Farming and raising cattle also becomes more complicated as there is less greenery and the crops do not get enough water. The higher or lower temperature than normal can also make chronic health problem worse. The burden on the lungs, the heart and liver can significantly increase as well.

  • Natural catastrophes

With climate change, the likelihood of catastrophic events, such as forest fires and typhoons increases considerably. And it also affects humans, plants and animals alike.

  • Food and water shortages

With farming problems and drying up of the rivers, there is less food and water for everyone.

What To Do?

At present, there are multiple initiatives that try to counteract climate change:

  • planting more trees – so they would take up carbon dioxide from the atmosphere
  • using filters in factories and transport
  • changing farming, using more advanced methods of growing crops and raising cattle
  • installing air filters in towns
  • using cleaner sources of energy (water, wind, sun)
  • using new methods of disposing garbage
  • monitoring forests to prevent fires
  • using novel building methods
  • And many more new approaches!

It is time to accept that we influence our whole planet with what we are doing. Climate change is a reality, and we need to take action to protect ourselves and every living being that lives on this planet with us.


Links and further reading:

[1.] – greenhouse image

[2.] – greenhouse effect diagram 

[3.] – coral bleaching image

[4.] The Impact of Climate Change on Human Health in the United States: A scientific Assessment (n.d.).