If carbon in the air in the form of carbon dioxide is so small (.035%), what is the problem?
Carbon dioxide is one of the class of gases known as greenhouse gases. The earth receives energy in the form of light and heat from the Sun. Some of this is reflected back into space. Carbon dioxide in the air can absorb heat and reradiate it, some of which returns to earth causing the earth to be warmer. This is much like a real greenhouse which uses sun light to capture heat and be warmer for the plants inside it even though outside the greenhouse is much cooler.
If the earth had no greenhouse gases, it is estimated that the earth would be 90º F (32ºC) cooler leaving much of the land area in tundra like frozen state. A big difference from such a small amount of greenhouse gases.
Since the amount of carbon dioxide in the atmosphere is very small, and the effect of greenhouse gases are so large, increases in carbon dioxide can have very detrimental effects on increasing the temperature of the earth. This is what is known as Global Warming.
Global Warming, if left uncontrolled, would cause the ice caps to melt, raising the ocean levels possibly 230 feet and inundate many of the earth's costal area. The probability of stronger and more frequent hurricanes increases as well as severe flooding in some areas with extended droughts in others.
What Part of this Problem is Mine?
Activity that causes carbon dioxide emissions contributes to the carbon problem. The amount of carbon dioxide released because of your personal activity is called your "carbon footprint". Almost all activity that uses energy contributes to your carbon footprint. From taking a hot bath to driving your auto to a store and the items you purchase releases or has caused the release of carbon dioxide into the atmosphere. Just about all human activity, even the simple act of breathing, contributes to the carbon problem.
What Can I Do?
Reduce the amount of carbon dioxide you personally contribute to the atmosphere. This may be accomplished by reducing carbon generating activities. Using more efficient sources of energy and light will reduce carbon dioxide in that when less electricity is needed, less coal or oil is burned. Public transportation will reduce the amount of fuel burned per person. Walking or riding a bicycle is even less carbon generating.
Giving up my automobile and walking everywhere is impractical!
Purchasing carbon credits or carbon offsets may be the answer for you.