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• What climate change is
• Where greenhouse gases come from
• How climate change affects us
• What you can do to help stop climate change
• How Ontario is taking action on climate change
•  

What climate change is 

Our atmosphere is full of invisible gases, some of which are greenhouse gases. Greenhouse gases insulate the Earth. They trap the sun's heat and keep our planet warm enough to sustain life.

Some greenhouse gases in our atmosphere do exist naturally. But a large portion of the greenhouse gases in our atmosphere today have been, and continue to be, created by humans. This means that more of the sun's heat is being trapped than the Earth actually needs.

In fact, too much heat is being trapped, and the planet is warming too much. This is what's known as global warming. Global warming is affecting weather patterns all over the world and this effect is what's known as climate change.

A region's climate means the usual weather patterns and conditions of a region. So, a change in weather patterns and conditions is a change in climate.

The world's weather patterns are changing. This includes temperature changes (warming in some places and cooling in others) and altered rainfall patterns, as well as more frequent occurrences of hazardous weather events like heavy spring rains and heat waves.

Changing climates pose risks to the health and safety of people, wildlife, forests, farms and water supplies. This is why it's so important for us to take action to stop it.

Where greenhouse gases come from 

Some greenhouse gases in our atmosphere exist naturally, but many of them are the result of human activities. Greenhouse gases come from:

• our cars, vans and trucks
• the power plants that light, heat and cool our homes
• the factories that produce the goods we consume

The average Ontarian generates about five tonnes of greenhouse gases every year.

How climate change affects us 

In Ontario, we can expect average temperatures to rise by as much as 3 to 8 degrees Celsius over the next century. Warmer temperatures may result in milder winters, longer growing seasons and a higher frequency of severe weather events such as record-breaking storms, floods, droughts and heat waves. The expected changes in our climate will have a significant impact on Ontario’s ecosystems, us and our communities. Some specific outcomes of climate change in Ontario may include:

• more extremely hot days (above 35°C), increasing the risk of heat stress-related illness among the old, the young and those with chronic lung diseases such as asthma.
• less snow but more freezing rain – which can down transmission lines and presents safety risks to road and air traffic.
• changes in wildlife habitats, which would adversely affect Ontario’s species and biodiversity.
• longer growing seasons, which can affect crop selection and yields.
• increased risk of warm-climate diseases such as Lyme and West Nile diseases and malaria which can spread through insects taking advantage of warmer winters.
• a drop in Great Lakes water levels by as much as one metre by 2050, jeopardizing shipping, fisheries, water quality and supply.
• increase in gas and home heating prices in order to cope with temperature extremes.

What you can do to help stop climate change 

Every day we make choices that affect our environment. When we make smart choices, the benefits add up — for our planet and Ontario. We’ve dedicated an entire website to help individuals take action on climate change. Please visit ontario.ca/yourenvironment to learn what you can do.

How Ontario is taking action on climate change 

Ontario is responding to climate change in two distinct ways: we’re taking action to reduce our production of greenhouse gases and we are changing the way we do things so we can adapt to our already changing world. Please explore the rest of this section to learn the specific ways we’re accomplishing these goals.