Carbon dioxide (CO2) is an odourless, colourless gas that is vital for natural cycles on Earth. People and animals inhale oxygen (O2) and exhale carbon dioxide. Plants do the opposite during the day.
Plants need CO2 in order to grow, just as people need oxygen in order to breathe. Algae in the ocean also absorb lots of CO2 and ‘breathe out’ oxygen. Without oxygen, life on earth would not be possible.
Humankind is adding extra CO2 to the atmosphere by burning fossil fuels, which increases the concentration of carbon dioxide. The Earth’s temperature is gradually rising because heat, which the atmosphere would otherwise release at night-time, is retained. This is called the greenhouse effect.
|Last modified:||08 June 2017 11.37 a.m.|