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Climate Change
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What is Climate Change?
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Difference GLOBAL WARMING
is the increase of the Earth’s average surface temperature due to a build-up of greenhouse gases in the atmosphere. CLIMATE CHANGE is a broader term that refers to long-term changes in climate, including average temperature and precipitation.
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The earth is getting warmer…
Scientists say: The earth is getting warmer… 20th century the warmest globally in past 1000 years 1980s and 1990s warmest decades on record The Earth is experiencing a change in its climate – one that will affect our environment, our economy, and the way we live for years to come.
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…and the warming will continue
Scientists predict average temperature increase of up to ºC in next 100 years Small changes in average temperatures make a big difference: All indications are that the warming we have been experiencing is going to continue. The Intergovernmental Panel on Climate Change, which brings together scientists from around the world, including Canadian scientists, issued its Third Assessment Report in January They concluded that average global temperatures could increase by anywhere from 1.4 to 5.8 degrees over the next century. To give a sense of what that means, during the last Ice Age, average temperatures were only about 5 degrees cooler than they are now. The five degrees of warming that ended the Ice Age was enough to melt the vast ice sheets that covered North America. Average temperatures today are only about 5ºC warmer than they were during the last Ice Age
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How do we know this is happening?
Temperature records - to 1860 Ice cores, sediment cores, tree rings - evidence dating back several thousand years How do we know what has happened in the past, and how do we predict the future? Scientists use a variety of tools. Reliable global temperature records only exist back to However, ice cores, tree rings, and coral reefs all release evidence of temperature change going back many millenia. They tell us that climate is variable, and that we have always experienced changes in our climate. The difference today is in the speed of the change and its magnitude. Today, we use sophisticated computer models to determine future projections such as the ones we just saw. Canadian models are considered among the best in the world. Computer modeling for future predictions: Canadian model among best in world
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Why is this happening? So scientists have told us that temperatures have increased in the past and will likely continue to increase. But our climate has always changed. Climate variability is a natural phenomenon. But why are temperatures increasing so much? What is it about these changes that make them different from other periods of changing temperatures in the Earth’s history?
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The Greenhouse Effect Some
energy is reflected back out to space Earth’s surface is heated by the sun and radiates the heat back out towards space Greenhouse gases in the atmosphere trap some of the heat Solar energy from the sun passes through the atmosphere
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Ozone: exists naturally in the Halocarbons:
The Greenhouse Effect is normal… without it Earth would be in a deep freeze! …But when greenhouse gases like these become more concentrated in the atmosphere, the Greenhouse Effect increases and causes global temperatures to rise… Carbon dioxide: released through burning fossil fuels Water vapor: the most common gas Methane: from wetlands, rice paddies, animal digestive processes, landfills and sewage treatments Nitrous oxide: from soils and the ocean Climate change has been called the most serious environmental and economic problem the world is facing. This presentation is designed to give you a better understanding of the science of climate change and what it could mean for our lives. It tells how all parts of Canadian society are meeting the climate change challenge, as well as letting you know how you can “do your bit” for climate change. Ozone: exists naturally in the upper atmosphere Halocarbons: human-made chemicals
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Human activities are intensifying the greenhouse effect
Deforestation Electricity Industry Over the past century, average global temperatures have increased by 0.6 degrees. In Canada, they have increased by one degree. The information in the video shows the cumulative change in average annual temperatures over the years. Transportation The use of fossil fuels has had the greatest impact on global warming.
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warmer What’s wrong with temperatures?
Warmer temperatures have a way of sounding awfully good – particularly in the winter. But scientists tell us that the consequences are not going to be all positive – and, indeed, we may be seeing some of them already. (nb: go to next slide for summary, or skip next slide to go on to detailed discussion of impacts)
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Climate Change different places different ways
will effect different places in different ways
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Climate Change Average annual temperatures could increase by about 4°C by the end of the century Increased risk of drought, dust storms, and insect infestations for agriculture Longer, hotter summers will increase evaporation, reduce water levels in lakes and rivers – could increase demands on groundwater Ecosystems could shift northward Extreme and severe weather events could become more common In fact, as this slide shows, 1998 was the warmest year on record in Canada – and internationally. In Canada, the temperature was, on average, 2.5 degrees above the mean for It was the second warmest winter (1987 was the warmest) and the warmest spring, summer and autumn in Canada since Environment Canada began collecting nationwide temperature records in 1948. If the climate were not to change, we could statistically expect a year like this once every 1670 years.
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Actions by individuals
account for 28% of greenhouse gas emissions each year - equal to six tons per year
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Personal GHG Emission Sources
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Idling our vehicles: produces unnecessary pollution that contributes to climate change, smog and health problems; wastes fuel and costs us money; and is not good for vehicle engines.
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More than a third of parents idle their vehicles while waiting to pick up their children
Children are particularly vulnerable to air pollution because they breathe faster than adults and inhale more per kilogram of body weight
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What can you do?
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What can you do to help solve the problem?
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Taking action to reduce emissions will slow the rate of climate change, save money and produce other environmental and health benefits Some Examples: Recycle or compost as much as possible Turn off your computer when not in use Walk or bike for short trip Get involved in actions in your community
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Simple Things To Do Turn off your computer or the TV
when you’re not using it. Take shorter showers. Heating water uses energy. Keep rooms cool by closing the blinds, shades, or curtains. Turn off the lights when you leave a room. Use compact fluorescent bulbs.
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Be Bulb Smart—Use CFLs What’s the difference? 500 lbs. of coal Compact
Fluorescent Incandescent 500 lbs. of coal 1,430 lbs. CO2 pollution avoided $30 saved
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Simple Things To Do Dress lightly when it’s hot instead of turning up
the air conditioning. Or use a fan. Dress warmly when it’s cold instead of turning up the heat. Offer to help your parents keep the air filters on your AC and furnace clean. Walk short distances instead of asking for a ride in the car. Plant a tree. Recycle.
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