A greenhouse is a house made of glass. It has glass walls and a glass roof. People grow vegetables and flowers and other plants in them. A greenhouse stays warm inside, even during the winter. During the daylight hours, a greenhouse gets warmer and warmer and stays pretty warm at night too. This is because the heat received from the sun is trapped inside the greenhouse by the glass.

The Earth is also like a greenhouse. During the day Earth’s surface warms up in the sunlight. At night, the surface cools releasing the heat back into the air. But some of the heat is trapped by gases like carbon dioxide in the atmosphere. These gases, called greenhouse gases, work like the glass walls and the roof and keep the earth warm. This is global warming and it is making the earth a dangerous planet. Unfortunately, we are making the earth too hot. We are using oil, gas and coal for running cars, buses, trains, planes, power stations and so on. These fuels have carbon in them. This carbon and other gases trap the heat in the atmosphere and do not allow the earth to cool down. As a result, the earth gets hotter.

As a result of global warming, the ice on the earth’s surface is melting fast due to extreme heat. Oceans and seas are warming too. All the ice that melts will fill up the oceans and seas and they will overflow on land. Thus a huge area of land will go under water. Some of the best land for growing food is also the most low-lying. That means it will be flooded first. Even some big cities like London, Kolkata and Bangkok will get flooded. That means thousands of people will lose their houses and land and they will go hungry. Moreover, as the earth’s climate warms up, the weather gets more violent. Storms and cyclones will become more powerful. More areas will get drier and turn into deserts. There will be heavier rains too. So there will be more floods and river erosion.