Carbon dioxide (CO2) is invisible. You can’t see it. But you can feel its effects. Particularly when it gets really hot. CO2 is the greenhouse gas most responsible for climate change. It is emitted on the surface of the planet by human activity. What is “human activity?” This could be industrial activity, recreational activity, or just a daily activity. All of this and more produces CO2, which goes up into the atmosphere and stays there, where it traps heat and warms up the planet (although some of it comes back down to Earth and gets absorbed by the oceans and the forests).
CO2 comes from industrial processes, such a oil refining, coal plants and manufacturing. But it also comes from you. It is emitted from the car you drive. The electricity you use is produced by power plants that emit CO2. The food you eat adds to your carbon footprint, because food production produces CO2.
Whether or not you realize it, you have a very intimate relationship with CO2. All of us do. Each of us gives off CO2, by breathing, eating, driving, by using energy to heat our homes, the production of which produces CO2, which goes into the atmosphere and can stay there – for hundreds – thousands – even tens of thousands of years.
So drive less, use less energy. Eat less. You’ll stay fit and help save the planet at the same time. In April 2014, for the first time in recorded history, monthly concentrations of CO2 in the atmosphere topped 400 parts per million (ppm) throughout the northern hemisphere.
The greenhouse gases that cause climate scientists concern, because of their tendency to trap heat are carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O) and halocarbons or CFCs (gases containing fluorine, chlorine and bromine). Water vapor is also a greenhouse gas but stays in the atmosphere a limited time and does not affect climate.
Greenhouse gases stay in the atmosphere from anywhere from several months to many millennia. Much of the CO2 we send into the sky is absorbed by the ocean, but much of it stays there for thousands of years – and can stay there for hundreds of thousands of years. This is what is changing our climate and why CO2 emissions are such a concern.