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Climate change is any long-lasting important changes in a region's average weather pattern, including temperatures, rainfall and wind patterns. The changes may last for decades or millions of years.
The Greenhouse Effect
Earth, like the other planets, absorbs the Sun's rays and radiates the heat back out into space. However, there are gases in the atmosphere surrounding Earth that trap the heat and reflect it back. This is like the way a greenhouse works for plants: the glass round the outside traps the sun's rays, making the inside warm even if it is cold outside. That is why the gases in Earth's atmosphere are called the greenhouse gases.
The more greenhouse gases there are in the atmosphere, the more heat is trapped. For example, Venus has too much of these gases and the planet is extremely hot with a temperature on the surface over 400 degreees C.
Of course if there are less greenhouse gases, then less heat is trapped. For example, if there weren't any greenhouse gases around Earth, it would become a frozen desert.
There are several greenhouse gases and each has its own part to play in trapping the sun's heat. They are naturally in balance, but changes in that balance can affect Earth's temperatures. Greenhouse gas concentrations have risen and fallen naturally throughout Earth's history, causing hot and cold periods of time, such as an ice age. However, in more recent decades scientists say that the changes have resulted from human activities.
Humans have been pumping tonnes of these greenhouse gases into the atmosphere from factories, power stations, cars and planes. When forests are burned more gases are released. The level of gases is growing too fast and too much heat is being trapped. This is causing the planet to warm up and will cause major problems such as:
Seas are getting warmer and sea levels are rising because glaciers and icebergs are melting in the warmer seas.
The weather is getting wilder, with stronger and more frequent storms and floods.
In other places there are long lasting droughts whch cause food crops to fail.
Global warming refers to the increase of average temperatures since the mid 20th century. It is generally agreed that the increasing greenhouse gases since the Industrial Revolution is a large factor of global warming.
Go here for some facts about the climate change debate
The following are sites with useful to information about climate change, global warming and the greenhouse effect
http://www.epa.gov/globalwarming/kids/
http://www.pewclimate.org/global-warming-basics/kidspage.cfm
http://www.timeforkids.com/TFK/specials/articles/0,6709,1113542,00.html
http://tiki.oneworld.net/global_warming/climate_home.html
Things we can do: http://library.thinkquest.org/CR0215471/global_warming.htm
If you use any part of this in your own work, acknowledge the source in your bibliography like this:
Thomas, Ron. & Sydenham, Shirley. Climate Change and Global Warming [online] www.kidcyber.com.au [2011]
updated July 2011 © kidcyber