Climate Change

Any long-term significant change in the average weather of a region or the Earth as a whole Includes changes in average temperature, precipitation and wind patterns

Potential Causes Carbon dioxide Plate tectonics Solar variation Volcanism Burning of fossil fuels Aerosols and CFCs Land use Deforestation Orbital variation Livestock

Deforestation The use of trees has more than doubled since the 1960’s Forests all over the world are over- harvested to meet the increasing demand for forest products Forests are also being cleared for raising livestock or developing urban areas.

Ozone Layer Depletion CFCs are still being used in a variety of industrial and household products, such as aerosols and cleaning solvents CFCs destroy the ozone layer that protects the life on Earth from the sun and UV rays.

Global Warming The increase in the average temperature of the Earth’s troposphere and oceans since the mid-20 th century and its projected continuation

What big event has happened since the mid-20 th century?

Effects of Global Warming Rising sea levels Glacier retreat Arctic shrinkage Extreme weather systems

Causes of Global Warming The scientific consensus is that global warming is due to the increase in atmospheric greenhouse gases due to human activity

The Greenhouse Effect The absorption of solar radiation by greenhouse gases Greenhouse gases include water vapour, carbon dioxide, methane, nitrous oxide, and ozone These gases ‘trap in’ heat within the troposphere

The Greenhouse Effect

Signs of Global Warming in Canada Seals and polar bears becoming endangered due to the thawing in the Arctic. Increase in the number of icebergs in the Labrador Sea. Changing direction of ocean currents in the North Atlantic. Rising sea level in Charlottetown, PEI. More thunder and lightning in the north Melting glaciers in the Rocky Mountains

What Can Be Done? Energy conservation/efficiency Limit deforestation Afforestation: plant new trees Alternative energy sources

The Kyoto Protocol An international agreement to reduce greenhouse gas emissions This involves making efforts to burn less fossil fuels This also involves moving away from fossil fuel energy sources (coal, oil, and gas) to renewable sources of energy (wind, hydro, and solar) Canada signed the agreement in 2002 and currently all countries have signed except for the USA.