CLIMATE CHANGE
INTRODUCTION
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the heat, preventing it from escaping. These gases forming a layer around the Earth are often called greenhouse gases (GHG). They act like the plastic cover of a farmer’s greenhouse – letting in the sunshine, but keeping in the heat. This process leads to global warming and climate change.
limate Change is a major issue of our time. In the past few years, temperatures all over the world have become a little hotter. The ice at the North Pole and South Pole and snow capped mountains is slowly melting. The sea level has risen. There has been an increase in heavy rainfall, frequent droughts, and violent storms.
THE GREENHOUSE EFFECT
Scientists think these changes are partly because of human actions. When we burn fossil fuels such as petroleum, the gas carbon dioxide is produced. Cattle, rice paddies and ploughing new land produce methane gas. Today we produce so much carbon dioxide and methane that natural habitats such as forests, grasslands and wetlands cannot absorb them all.
Carbon dioxide and other greenhouse gases in the atmosphere trap heat, keeping the earth warm.
Some sunlight that hits the earth is reflected. Some is absorbed and becomes heat.
During the day the sun warms the Earth, and at night the heat escapes back into space. Today, however, carbon dioxide, methane and other gases are forming a layer above the Earth. This layer of gases traps some of
Illustration by John Mwacharo
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