Carbon dioxide and methane as greenhouse gases

• Greenhouse gases maintain temperatures on earth high enough to support life and include water vapour, CO2 & CH4.
• The greenhouse gas effect: electromagnetic radiation at most wavelengths (both long and short) from the sun passes through the Earth’s atmosphere, the Earth absorbs some radiation and thus warms up, but some heat is radiated from the Earth as infrared radiation.
• Some of the IR radiation is absorbed by greenhouse gases in the atmosphere, causing the atmosphere to warm up leading to the greenhouse effect and global warming.
• Human activities which contribute to an increase in greenhouse gases in the atmosphere include activities that increase levels of CO2 & CH4, such as driving, consuming electricity, raising livestock, and the decay of organic waste in landfill sites.
• Based on peer-reviewed evidence, many scientists believe that human activities will cause the temperature of the Earth’s atmosphere to increase at the surface and that this will result in global climate change.
• Global climate change: an increase in average global temperature is a major cause of climate change, with potential effects including extinction of species, raising sea levels due to the melting of polar ice caps, migration of people due to drought or flooding, and a decrease in crop yield for all major world crops.
• Carbon footprint: the total amount of CO2 and other greenhouse gases emitted over the full life cycle of a product, service or event.
• Carbon footprint can be reduced by reducing emissions of carbon dioxide and methane, for example by using less electricity, reducing the amount of travel or transportation, and planting more trees.
• Action to reduce carbon footprint may be limited because it’s more difficult, can be more expensive, and planting trees takes away land that could be used to grow crops.