Climate change is a change in the "average weather" that a given region experiences. When we speak of climate change on a global scale, we are referring to changes in the climate of the Earth as a whole. The rate and magnitude of global climate changes over the long term have many implications for natural ecosystems.
For thousands of years, the Earth's atmosphere has changed very little. The temperature and the careful balance of greenhouse gases have been optimal for humans, animals and plants to survive. But today we are having problems keeping this balance. By burning fossil fuels to heat our homes, run our cars, produce electricity, and manufacture all sorts of products, we are adding more greenhouse gases to the atmosphere. These activities are changing the atmosphere at a greater rate than humans have ever experienced.
Climate change is more than a warming trend. Increasing temperatures will lead to changes in many aspects of weather, such as wind patterns, the amount and type of precipitation, and the types and frequency of severe weather events. Such climate change could have far-reaching and/or unpredictable environmental, social and economic consequences.
Climate Change and Health (fact sheet)
Climate Change and Your Health (poster)
Canada's Top Ten Weather stories for 2009.
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