Green House Effect & Global Warming

What is a Green House that farmers use to grow plants?

Function of the Green House The green house is made up of glass or plastic (walls and roof) Allows sunlight to filter through and warms up the air The heat is also absorbed by plants, soil and other objects

Function of the Green House The heated surfaces emit heat back in the atmosphere in the form of infrared radiation Infrared radiation has difficulty leaving the green house and cannot escape The glass in the green house traps the infrared radiation or heat

Green House Effect Particular gases in the earth’s atmosphere acts like the glass in the green house These gases are called Green House Gases. Eg. Carbon dioxide, Methane, CFC

Green House Effect Green house gases are responsible for keeping the earth warm Without these gases the earth would be too cold for organisms to exist

Green House Effect Some of the radiation from the sun is reflected by the earth’s surface and atmosphere Some is absorbed by the earth’s ocean and land The warmed ocean and land then emit infrared radiation (heat)

Green House Effect Not all this infrared radiation goes to space Some is trapped by the green house gases, keeping the earth warm

WHY? The earth’s temperature must remain constant We must not upset the balance of the gases WHY?

Do man’s activities produce green house gases?

Yes

Example: -Burning of fossil fuels - Cutting of trees - Use of CFC’s

Therefore we have an increase of green house gases in the atmosphere. What do you think will be the result of an increase in green house gases?

A lot of scientists agree that man’s activities are making the natural green house effect stronger OR Some scientists will say “Enhancing green house effect”

Global Warming More green house gases More heat ( infrared heat) is trapped Increase in temperature Earth gets warmer Global warming

Global Warming Global warming is defined as the increase of the Earth’s surface temperature due to a build up of green house gases in the atmosphere

Effects of Global Warming Rise in temperature can be terrible for us High temperature will make the ice caps melt

Effects of Global Warming This will cause sea levels to rise Coastal flooding harming plants and animals

Effects of Global Warming Changes in weather patterns due to the change in proportion of more water to land Some areas will have: -Storms - Drought - Increase in rainfall

Effect of Global Warming Changes in weather can have an effect on production of crops. This will lead in some countries not having enough food. Future Carbon Emissions  will probably increase, especially in China and developing countries  This will result in a likely doubling of carbon dioxide levels within 150 years, due to  Increased coal usage  And increased natural gas usage,  although petroleum usage is likely to decrease due to increased cost and decreasing supply 

Global Warming As temperature and weather changes, homes of plants and animals will be affected Example: - when the ice in the Arctic melts, polar beers and seals will have to find a new home

Each of us must take steps to protect our Earth's climate. Our take-home message… Each of us must take steps to protect our Earth's climate.