As you inhale, probably without notice, you are breathing the same air that circulated through the lungs of paupers and kings, presidents and refugees, dinosaurs and trilobites. We breathe oxygen that was once dissolved in the oceans, once exhaled from a tree, and probably passed through the lungs of our children and ancestors as well. We inhale oxygen, and exhale carbon dioxide.

Carbon dioxide is a useful gas. Plants take exhaled carbon dioxide, filter out the carbon, and use it to build stems and leaves. We use carbon dioxide to drive our pneumatic tools, put the fizz in soda, and the pop in Pop Rocks candy. Bakers use yeast, baking soda and baking powder, which release carbon dioxide causing dough to rise. Carbon dioxide is even used to remove caffeine from coffee, and create foam in fire extinguishers.

Carbon is the sixth most abundant element in the known universe. Carbon can be found in the solid form as living things, coal, diamonds, and 10 million other compounds. One of which, graphite, I use in the form of pencils almost daily. Carbon is second to oxygen as most common elements in human bodies. Without carbon, life on our planet would be impossible.

So why is carbon getting such a bad rap?

The Carbon Cycle: In the natural carbon cycle, billions of tons of carbon dioxide are removed from the atmosphere by growing plants and the oceans. Forests and fields are called "carbon sinks" because they literally scrub the carbon dioxide from the air. The same trees release carbon back into the atmosphere when they die and decay. For eons, this natural system has been mostly in balance, with the amount of carbon being emitted and removed being roughly equal. Only an occasional volcanic eruption would cause a relatively minor fluctuation in the global carbon cycle.

The Industrial Revolution changed all that when humans started burning oil, coal and gas, cutting down forests, and plowing up fields. As the result of human activity, atmospheric carbon concentrations have risen 35 percent above what they were before the Industrial Revolution, according to information provided by the Environmental Protection Agency.

We have witnessed carbon concentrations leap from 280 parts per million before the Industrial Revolution to 383 ppm today, a record high for the past 600,000 years.

Atmospheric Carbon: Globally, humans produce about 70 million tons of atmospheric carbon per day. The main ways we do this are through deforestation, generating electricity, burning fossil fuels and wood, industry and agriculture.

Carbon Emissions: Author Michael Pollan wrote in "An Omnivoire's Dilemma: A Natural History of Four Meals," "More than a third of global greenhouse gas emissions can be attributed to the saw and the plough." Pollan is factoring the clearing of rainforests and burning of trees — which can account for 10 percent of global carbon emissions — on top of the loss of carbon sinks and the emissions created by disturbing the carbon stored in the soil. Add to Pollan's figure the emissions generated by transporting food, consumer goods, and transportation in general and you have another 25 percent. About 40 percent of the Earth's yearly global carbon dioxide emissions, 6.5 billion tons, come from generating electricity, mainly from coal-fired power plants. Industry accounts for the rest, a large portion of emissions coming from superheating limestone to create cement.

Carbon Capture and Sequestration: Scientists are devising ways to capture smokestack emissions from coal-burning plants and pipe them to underground reservoirs that once contained oil or natural gas. This keeps carbon emissions out of the atmosphere, at least temporarily. Scientist Christopher Williams pointed out in a recent research paper that carbon emissions could be stored more efficiently in the soil. This would increase the soil's fertility, and food crops raised on it would help combat cancer, birth defects and premature aging.

Carbon Footprint: U.S. Green Building Council Chairman Rick Fedrezzi recently said, "Some day our income tax will be tied to our carbon footprint." The average American household has a carbon footprint of about 22,000-50,000 pounds per year. Your carbon footprint is a measurement of carbon emissions generated by your specific lifestyle. Find out what yours is at www.carbonfund.org. After you get over the shock, you might want to lower that figure. Going on a "low-carbon diet" doesn't mean you need to stop breathing, read David Gershon's book "Low Carbon Diet" and find out how to trim 5,000 ugly pounds of carbon from your carbon footprint.

Carbon Offsets: The most popular method of lowering your carbon footprint is to offset all or part of your emissions by purchasing carbon credits, or offsets, in the form of wind energy being fed into the national electric grid. You can find out more about this at www.NativeEnergy.com.

Shawn Dell Joyce is a sustainable artist and activist living in a green home in the Mid-Hudson region of New York. Contact her by e-mail Shawn@ShawnDellJoyce.com. To find out more about Shawn Dell Joyce and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate website at www.creators.com.

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