Earth’s surface warms up in the sunlight. The warm earth reemits some of the radiation back into space. Some of this reemitted radiation escapes into space and the rest of it is reflected back down to Earth due to the presence of greenhouse gases (GHG) in the Earth’s atmosphere. Greenhouse gases such as carbon dioxide CO2, methane (CH4), Nitrous oxide (N2O), and water vapor trap some of the sun’s heat before it escapes into space and keeps the Earth warm enough to sustain life. This is called the Greenhouse Effect.
Without the Greenhouse Effect, our Earth would probably look a lot like Mars. In the absence of greenhouse gases, all of the remitted radiation would escape into space and the planet would be very cold. Since the industrial revolution began in 1750, the greenhouse effect has been enhanced because of the increase in emission of greenhouse gases (GHG’s). With the increase in the amount of GHG’s in the atmosphere, more radiation gets trapped causing the earth to warm beyond it’s ideal temperature. This process is called Global Warming. The accelerated warming of the planet will disrupt natural ecosystems and human civilization. Rising sea levels and decreased snow cover in Northern Hemisphere are some of the evidence of climate change.
Concentration of carbon dioxide is much greater than other GHG’s such as methane and nitrous oxide emitted into the atmosphere by human activities. This is mainly because large amount of CO2 is released into the atmosphere by burning fossil fuels via cars, power plants and industries. The global average level of atmosphere carbon has increased since industrial revolution from 280 parts per million to just under 400 parts per million at present. Climate scientists identify this level as the beginning of “danger zone”, at which more dramatic climate impacts become likely.
A transition to sustainable global energy mix is needed to mitigate global warming. Renewable energy reduces energy related CO2 emission significantly at a reasonable cost. Renewable energy such as solar, wind, bioenergy and geothermal are available around the world. Renewable energy has the technical potential to meet all of our energy needs.
A progressive carbon pricing system will discourage the use of fossil fuels, reduce greenhouse gas pollution and encourage businesses to make investments in renewable energy.
We can do many things to reduce our personal carbon footprints such as switching to clean renewable energy, use cleaner transport, add energy saving features to our home, adopt energy saving and water saving habits. Taken together these actions will have huge impact.