What is CO2?
CO2 is the chemical symbol for carbon dioxide, a greenhouse gas. Greenhouse gases are the gases present in the Earth’s atmosphere that stop heat escaping into space, keeping the planet warm enough for life. CO2 is probably the most significant of the greenhouse gases as it accounts for the largest proportion of the 'trace gases' in the atmosphere. It is thought that it's been in the atmosphere for over 4 billion of the Earth's 4.6 billion year geological history.
How is it created?
Atmospheric CO2 comes from a number of natural sources, mainly the decay of plants, volcanic eruptions and as a waste product of animal respiration.
It is removed from the atmosphere by dissolving in water (especially the surface of oceans) and through photosynthesis in plants. This is when plants use light energy, CO2, and H2O to make sugar.
The amount of CO2 taken out of the atmosphere is almost perfectly balanced with the amount put back into the atmosphere by respiration and decay. Small changes as a result of human activities can have a large impact on this delicate balance.
Why have CO2 levels increased over the last two hundred years?
Nobody knows for certain, but it is generally believed that an increase in the use of fossil fuels is responsible. Since the Industrial Revolution we have burnt fossil fuels to provide our light, heat and to run our cars. The trouble is that when we burn fossil fuels, we release CO2 into the atmosphere.
This has resulted in the concentration of CO2 in the atmosphere increasing by more than 30%.
The best case scenario for the increase in CO2 emissions predicts that the concentration of CO2 in the atmosphere will reach double the level of before the Industrial Revolution, in 2100. The worst case scenario brings this forward to 2045.
What happens if there is too much carbon in the atmosphere?
If there is too much CO2 in the atmosphere it increases the "greenhouse effect", trapping heat that would normally escape into the atmosphere. This causes the planet to heat up, which is believed to be the cause of climate change. Climate change is widely predicted to have a devastating impact upon the planet and people around the world.
What is your carbon footprint?
A carbon footprint is a measure of the impact our activities have on the environment in terms of the amount of greenhouse gases we produce. It is measured in units of CO2.
The average person’s carbon footprint in the UK is 9,400 kg, that's nearly nine and half tonnes!
Roshan Seebundhun, Architect
Reference http://www.co2now.org/
