"Well, it's simply an idea to offset the pollution that people may create in their day-to-day lives when you drive, when you pollute the air, when you perhaps heat your home or cool your home and create greenhouse gases," explains Dr. Walden, a North Carolina Cooperative Extension specialist.

"The notion here is that if you are going to continue to do that, can you do something else? Can you buy something else that will create an offset to the pollution?" he adds. "And this is where the notion of carbon credits comes, where you go off and you send money to some organization, who will then take that money and, for example, plant trees.

"The notion is you are going to plant enough trees such that those trees can absorb those greenhouse gases and, therefore offset, the pollution you are creating in your day-to-day activities. And this is becoming very, very popular. People can actually go on the Web and purchase these so-called carbon credits.

"Now that's the theory. I think one question that some have is whether the offset really does work," Walden says. "For example, if you are creating pollution in our country here but you are buying trees to be planted in Africa, is that really an offset? But so this certainly will, I think, become an idea that is going to get more investigation."