This video gives a brief overview of fast and slow carbon cycling on Earth. Satellite imagery of atmospheric carbon dioxide combined with vegetation demonstrates the uptake of atmospheric carbon dioxide by plants on land over the annual cycle. Young, fast carbon such as a banana comes from plants growing now. When we eat a banana and breathe out carbon dioxide, we do not add to the long-term atmospheric carbon dioxide level. Old, slow carbon such as coal has been locked away for millions of years. When we dig it up and burn it, atmospheric carbon dioxide increases over the long-term (i.e. decade and longer). One of the byproducts of burning carbon is black carbon or soot, shown over the Earth at night to highlight the correspondence between black carbon and city lights. More lights shine where more energy is generated, usually from burning fossil fuels.
As plants turn green and grow during spring and summer, they use carbon dioxide in photosynthesis and remove it from the air. When plants go dormant in winter, atmospheric carbon dioxide levels rise.
Black carbon or soot is released to the atmosphere through burning. In the Northern Hemisphere, soot is mainly released from burning coal and other fossil fuels. In the Southern Hemisphere, soot primarily comes from agricultural burning and clearing old growth forests.
Everybody has a carbon footprint through the choices we make about food, transportation and energy use. There are many ways we can reduce our carbon footprint (e.g. walk, ride a bike, take public transportation, buy local, waste less, compost, eat less meat, switch to renewable energy).
Science On a Sphere
