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GREENHOUSE EFFECTS GROUPS MEMBERS: a)Noor Syazlin bt Naim b)Sariah bt Mohd Salleh c)Nur Aain Mazura bt Che Mahtar

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What are greenhouse gases?

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Global warming

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Global warming potential (GWP) is a measure of how much a given gas can contribute to global warming over a given time period. It is measured relative to carbon dioxide

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The GWP of a gas is calculated using the following factors: molar mass of the gas Lifetime of the gas in the atmosphere Ability of the gas to be absorbed infra-red radiation

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Greenhouse gases compared The contribution of a greenhouse gas to global warming depends on its global warming potential (GWP) and the amount of that gas present in the atmosphere. Greenhouse gas Average % of atmosphere GWP After 20 years After 100 years water vapour carbon dioxide methane nitrogen monoxide 14 0.038 0.0002 0.00003 11 7225 289298

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Causes of climate change

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How scientists can help? To find out the current extent of the problem Predicts its future extent Analyses the available evidence eg: carbon capture and storage Investigate the viability of controversial solutions

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The role of co-operation STERN REPORT Stated that global warming could have a massive economic cost. KYOTO PROTOCOL reduce greenhouse gas emissions by a certain amount in a certain time.

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The effects of global warming Negative effects Positive effects

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POSITIVE EFFECTS The next ice age may be prevented from occurring. Northwest Passage through Canada's formerly-icy north opens up to sea transportation. Less need for energy consumption to warm cold places. Fewer deaths or injuries due to cold weather.

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NEGATIVE EFFECTS a)Increase in average global temperatures (AVT) - The AVT has increased by 0.6C over 140 years. - The climate could increase up to 6C in the next 150 years.

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b) Shrinking ice caps - The artic sea ice has decreased in area by 38% since 1979. - This melting is caused by rising temperature. - Leads to loss of animal habitats (eg: polar bear) NEGATIVE EFFECTS

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c) Rising sea level -Global average sea levels has risen 5cm in 1992. -This is at least partly due to melting ice caps. -It leads to an increase in flooding.

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d) Extreme local weather conditions -Local weather patterns are changing, with increasing incidences of extreme weather -Eg: flooding, storms, droughts NEGATIVE EFFECTS

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WHAT DO YOU THINK?

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Global warming: true or false?