The Science of Climate Change

  • Greenhouse gases, including carbon dioxide, methane and water vapor, trap heat in the Earth's atmosphere and warm the planet.
  • In general, the greenhouse effect is a good thing. Without greenhouse gases, the temperature on Earth would be too cold to support life. With too many, it would heat up beyond survivable levels. Earth is sometimes called the Goldilocks Planetbecause it is "just right."
  • Since 1958, the amount of carbon dioxidein the atmosphere has been measured from an observatory on Mauna Loa, a volcano in Hawaii.
  • The pre-industrial concentration of carbon dioxide in the atmosphere was 280 parts per million(ppm). As of March 2009, it has reached 387 ppm.
  • Today, the amount of carbon dioxide is higher than at any time in the last 650,000 years.And the Earth's average temperature is increasing faster than ever before.

The Intergovernmental Panel on Climate Change projects that temperatures will rise 3.2 - 7.2 degrees Fahrenheit in the 21st century. Dramatically reducing levels of global warming pollution may keep the rise in the lower part of this range.

Important Climate Change Terms

This describes the total of all weather occurring over a period of years in a given place. It is the average weather condition of that place. Climate tells us what it’s usually like in the place where you live.

For example, some countries like Cameroon, Ghana and Liberia are all in the tropical wet region of Africa. They have a very sunny, hot and wet climate all year round. However, there may be very different day-to-day weather conditions in each village or town in these countries.

Weather is all around us. Weather may be one of the first things you notice when you wake up. Weather describes whatever is happening outdoors in a given place at a given time. It can change a lot within a very short time. For example, It can be windy at night, rainy in the morning, hot and sunny at noontime, and even back to windy before sunset. It includes daily changes in rainfall, temperature and wind in a given location.


Greenhouse is also another word you should know about. Have you ever seen a greenhouse? In some countries, people build a small glass house to plant crops in it. It is built to keep the sun's heat from escaping from the glasshouses.

In a way, the earth is like a glasshouse. The earth has some very important gasses in the atmosphere that keeps us warm.

Some of these gases are water vapour, carbon dioxide, nitrous oxide and methane

When the sun heats the earth, these gases keep the heat on the earth's surface. Without these gases, heat would escape back into space and Earth’s average temperature would be about 60°F colder.


What's the difference between weather and climate?

Weather is what the forecasters on the TV news predict each day. They tell people about the temperature, cloudiness, humidity, and whether a storm is likely in the next few days. That’s weather! It is the mix of events that happens each day in our atmosphere. Weather is not the same everywhere. It may be hot and sunny in one part of the world, but freezing and snowy in another.

Climate is the average weather in a place over many years. While the weather can change in just a few hours, climate takes hundreds, thousands, even millions of years to change.


Click on map for forecast