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GLOBAL WARMING. D. Crowley, 2008. GLOBAL WARMING. To know what causes global warming, and how this can affect the global climate. EARTH. The atmosphere is a thin layer of gases, surrounding the Earth
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GLOBAL WARMING D. Crowley, 2008
GLOBAL WARMING To know what causes global warming, and how this can affect the global climate
EARTH • The atmosphere is a thin layer of gases, surrounding the Earth • Certain gases in the atmosphere trap heat, reflecting it back to the Earth’s surface, warming it • This is similar to the glass in a greenhouse, which traps heat inside it (trapping of heat by the Earth’s atmosphere is known as the greenhouse effect)! • Without this atmosphere the Earth would be too cold for life to exist
INCREASING • Carbon dioxide is the main greenhouse gas involved with the warming of the Earth (as well as methane) • Human activity is producing more carbon dioxide (combustion engine) and methane (cattle and drilling) • Increasing the greenhouse gases increases the amount of heat the atmosphere traps • This increased greenhouse effect makes the Earth warmer, leading to global warming
TRAPPING HEAT • Greenhouse gases trap some of the Sun’s heat, so warming the surface of the Earth…
CAUSES • There are a variety of reasons why more greenhouse gases are present in the atmosphere, but certainly human activity is greatly responsible… • Huge numbers of cars and factories mean enormous levels of carbon dioxide are produced • Large scale deforestation reduces the number of plants which can remove the carbon dioxide (via photosynthesis) • Methane levels are also rising (via cattle farming; paddy fields; and drilling for oil and gas)
RATE • Carbon dioxide has steadily risen as has the average temperature of the Earth over the last 150 years…
EFFECTS • Rises of just a few degrees in world temperature could have a dramatic impact on the world climate – global weather patterns may change, causing drought for some areas, and flooding for others • Melting of ice caps could raise sea levels causing flooding of low-lying land (as well as habitat destruction)
SPEAK • Your task is to summarise the effects of greenhouse gases and global warming problems global warming will cause for the Earth / ways we can combat global warming • This can be done via a letter to Parliament / an add campaign to increase awareness of the problems / changes you can do to do your part in decreasing the production of greenhouse gases