What is global warming?

Global warming is the process of the earth's atmosphere heating up. (The atmosphere is the air that covers our planet like a blanket.) Over the last 100 years, the average temperature of earth's atmosphere has gone up 1° Fahrenheit. The weather has not changed exactly the same way in every area of the planet. But, scientists think that the rise in average temperature is already affecting the earth's climate.

What is the effect of global warming?

With more heat trapped on Earth, the planet will become warmer, which means the weather all over Earth will change. For example, summers will get hotter, and winters too. This may seem a good idea, but the conditions we are living in are perfect for life, and a large rise in temperature could be terrible for us and for any other living thing on Earth.

The effect of a change in the weather on plant growth may lead to some countries not having enough food. Brazil, parts of Africa, south-east Asia and China will be affected the most and many people could suffer from hunger.

Many animals and plants may not be able to cope with these changes and could die. This could cause the loss of some animal and plant species in certain areas of the world or everywhere on Earth.

In other parts of the world, the effects will be different, some places will become drier and others will be wetter. Although most areas will be warmer, some areas will become cooler. There may be many storms, floods and drought, but we do not know which areas of the world will be affected.

Why are greenhouse gases a problem today?

The greenhouse effect is not new. Carbon dioxide, nitrous oxide and methane have been keeping the earth warm for millions of years. In the past, nature produced just the right amount of greenhouse gases to keep earth at a balanced temperature.

Today, most scientists are pretty sure that the rising temperature can't be blamed on nature. Ever since the industrial revolution in the 1700s, humans have relied on machines for daily life. And many of those machines (like cars) give off, or emit, a lot of greenhouse gases. An increase in the release of greenhouse gases from human activities is throwing nature off balance.

How is global warming affecting the world?

The climate is a very complicated thing, but many scientists agree that the rising atmospheric temperature has already damaged the environment. Sheets of ice, called glaciers, are melting in Antarctica and other parts of the globe. As glaciers break off and melt into the oceans, they are adding warm water to the oceans and causing the sea level to rise.

Over the last 100 years, the sea level has risen 6-8 inches around the world. That means that land along the coasts is beginning to disappear under water. Bigger and warmer oceans are also adding to other weather problems caused by pollution in the atmosphere. Some places have received more rain, others have had bigger storms and a few areas in the world have experienced unusual droughts.

If the warming gets worse, as scientists expect, there may be some kinds of plants and animals that become extinct (disappear completely) because they can’t move to new homes. There may be more storms and floods. Sea level may rise so much that people have to move away from the coasts. Some areas may become too dry for farming.