Carbon. It’s a rather useful little element, and it does all sorts of neat things, bonding in all sorts of different was to make the basic building blocks for all living organisms on Earth. The energy that you burn every day as food is made from carbon bonded to hydrogen and oxygen in different ways, and it is this carbon that is released as carbon dioxide when you breathe out. Not only that but DNA, sugars, fats and proteins, the very building blocks of life are formed with a base made from carbon atoms.
In fact, all of life on Earth in it’s amazing complexity and diversity is possible due to the wonderful properties of this element. So if carbon is so great, why does it seem to be spending most of it’s time on the metamorphical elemental naughty step?
Simply put, there’s just a little bit too much in the atmosphere. Carbon dioxide is what we call a greenhouse gas. Thermal radiation (heat energy) from the Sun enters our atmosphere; a proportion of which gets absorbed by the Earth whilst some is reflected back into space. Greenhouse gases trap some of this heat energy that would otherwise simply leave the Earth, causing an increased global temperature. Think of it like a jumper, trapping the heat that comes from your body making you warmer, only on a planet-wide scale.
Now before you start shaking your fists skyward it should be noted that some greenhouse gases are really rather useful. According to NASA if there were no greenhouse gases the average temperature of this planet would be around 33 degrees Celsius lower than it is today. To put that into perspective the last ice age roughly 20’000 years ago which covered most of the UK under a sheet of ice saw an average global temperature around only five to ten degrees lower than present.
So carbon dioxide is a naturally occurring molecule, and has helped maintain a planet with a temperature warm enough to sustain life for the last four billion years. However since the industrial revolution the burning of fossil fuels by humans has increased the carbon dioxide concentration in the atmosphere rather dramatically.
Fossil fuels are the decayed carbon rich remains of ancient living organisms. For millions of years fossil fuels were deposited in the form of coal, oil and gas into the Earth. Fossil fuels contain carbon rich compounds (that is carbon bonded to other elements, mainly in this case hydrogen) which can be burned to produce lots of useful energy but also releases carbon dioxide as an emission.
Of course fossil fuels are natural, but the rate that they are being burned is not. We have used up fossil fuels that were deposited over hundreds of millions of years in only a few generations. This has caused the concentration of carbon dioxide in the atmosphere to increase, and is the primary cause of what is known as “global warming” the increase in Earth’s temperature due to man made emissions.
Most scientists agree that global warming is a real threat. Ice caps could melt, land could dry up, weather could get more unstable leading to increased flood and hurricane risk and entire ecosystems could be lost, unable to cope with rising temperatures.
To reduce the risk and effects of global warming scientists argue we must reduce our carbon emission. This means reducing energy consumption by recycling, being more efficient and changing our often wasteful lifestyle. We can also get clean energy from renewable resources that don’t burn fossil fuels and release carbon dioxide, such as solar energy, wind farms and tidal power.
