Over the course of Earth’s 4.5 billion-year history, the planet has experienced both tropical climates and ice ages many times. Yet since the last ice age – around 11,000 years ago – the climate has been relatively stable. So why are we all so concerned about climate change?
Put simply, it’s a question of greenhouse gases. The planet has always been wrapped in a layer of greenhouse gases. This layer acts like a blanket, keeping Earth warm and shielding it from the harsh cold of the universe.
However, as more greenhouse gases are released into the atmosphere, the protective layer is getting thicker. As it does, Earth’s average temperature rises. That causes serious results: changes in rainfall, rising sea levels, melting ice caps and other changes in nature. This is climate change. We’re already experiencing it today, and it’s set to get worse.
The major greenhouse gases as listed by the Centre for Clime and Energy Solutions are:
|Greenhouse Gas||Chemical Formula||Anthropogenic Sources||Atmospheric Lifetime1(years)||GWP2 (100 Year Time Horizon)|
|Carbon Dioxide||CO2||Fossil-fuel combustion, Land-use conversion, Cement Production||~1001||1|
|Methane||CH4||Fossil fuels, Rice paddies, Waste dumps||121||25|
|Nitrous Oxide||N2O||Fertilizer, Industrial processes, Combustion||1141||298|
|Tropospheric Ozone||O3||Fossil fuel combustion, Industrial emissions, Chemical solvents||hours-days||N.A.|
|CFC-12||CCL2F2||Liquid coolants, Foams||100||10,900|
|Sulfur Hexaflouride||SF6||Dielectric fluid||3,200||22,800|
You can find in-depth guides and informative videos about climate change on the Met Office website. Their Climate Guide pages are a great place to start if you’re interested in learning more about greenhouse gases and their affects on our planet. Please visit their website for references and more information – you can find this table in its original form at http://www.c2es.org/facts-figures/main-ghgs