Free Worksheets, Lessons, Quizzes

Greenhouse Effect

What is Greenhouse Effect?


Before learning about the greenhouse effect, you should first have a clear understanding of what is happening inside a greenhouse.


Have you ever been inside a greenhouse? 


A greenhouse is actually a glass building structure where plants are grown. Inside a glass house it is very warm even if, it is located in a very cold weather. The reason is the glass walls let the sun’s rays in but prevent the heat from getting out. Similarly, Earth’s surface and atmosphere stay warm when gases in the air trap heat from the sun. If you have experienced the temperature difference inside and outside a greenhouse, it would be very easy for you to understand the concept of greenhouse effect.


As you know our earth is enveloped by the atmosphere, which is a mixture of different gases. Each and every second these gases trap heat and keep in them, which is released to the air by the results of actions mostly done by humans on earth.


Now let’s assume our earth is inside a giant greenhouse.


So, what creates the glass walls of this green house? Definitely, the gases act as the glass walls of this greenhouse, which trap and keep heat from escaping into space, resulting earth to stay warm. This is what we call  greenhouse effect.


What are the gases responsible of causing the greenhouse effect?


We call these gases greenhouse gases. The main gases that cause the greenhouse effect are:


  • Water vapour (H2O)
  • Carbon dioxide (CO2)
  • Methane (CH4)
  • Chlorofluorocarbons (CFCs)
  • Hydrofluorocarbons  (HFCs)
  • nitrous oxide
  • Ozone (O3)


These gases also mainly involve in air pollution and the occurrence of acid rains.


Though some greenhouse gases occur naturally in the Earth’s atmosphere, according to scientists the amount of gases in the atmosphere has increased in the past few decades. Scientists believe the greenhouse gases are expected to raise the average global temperature of the earth over the next 50 to 100 years.


Now let’s see who is responsible of causing the greenhouse effect.


Sadly, the occurrence of greenhouse effect is mostly due to human activities. Look at the table below to know the gravity of the destruction done by humans to their world.


Gases and other pollutants

Discharged by

Carbon monoxide (CO)Vehicles
HydrocarbonsVehicles (This gas is produced when petrol is not fully burnt)
Nitrogen oxideVehicles, Power stations and factories
Sulphur dioxide (SO2)Power stations and factories
Carbon dioxide (CO2)Humans and other animals, Burning of fossil fuels
Chloroflorocarbons (CFC)Air-conditioners, refrigerators, perfumes and some sprays
Tiny particles of soot and dustFactories
LeadVehicles (in diesel, petrol), lead batteries, hair dye products


These are a few of many human activities which directly cause greenhouse effect. How? Huge amounts of greenhouse gases released to the air by these activities, trap and keep more heat in them, resulting our earth is getting warmer and warmer. This is what we call Global Warming.


To learn about global warming, how it occurs and how to reduce global warming, please read the lesson Global Warming.