You've probably noticed that I don't talk so much about "Global Warming" as I do "Global Climate Change." "Warming" is a real misnomer; while some areas are indeed getting hot (like Georgia and Australia, which has been experiencing what some say is a permanent drought), other places are getting colder and wetter (just ask anyone in the Pacific Northwest, where they've only had about four days of sunshine for the past month).

However, it's becoming clearer that climates around the world are changing – and whether this is a good thing or a bad thing (generally it's the latter, since messing with nature rarely turns out well), it's pretty obvious that we humans and our activities are causing it. Specifically, it's the use of fossil fuels and the release of excess carbon into the atmosphere.

If you are a science fiction fan, you're probably familiar with the theme of time travel, and how it's usually a bad idea to bring something out of the past into the present (as in Jurassic Park). When we pull petroleum and coal out of the ground however, this is what we in essence are doing. Petroleum and coal is basically solar energy that was absorbed by plants living half a billion years ago and more. When these plants died and the geography of the planet changed, this vegetable matter went into the ground, where it was subjected to immense geologic pressures. As you know, plants absorb and trap carbon dioxide. When fossil fuels are burned, it releases this ancient CO2 back into the atmosphere – adding to what's already there in the here and now.

If you want to know what the end of this process could look like, take a peek at the planet Venus. (The average surface temperature on Venus is around 800 degrees.)

One of the ways to head of this disaster is by carbon "sequestration" – storing excess carbon in the soil. And that's where new and more environmentally-friendly farming and gardening practices come in.

You know that plants absorb carbon dioxide and release oxygen. What you may not realize is this is how a plant feeds itself. You and I eat carbohydrates in the form of grains, root vegetables and so forth – which turns into sugar in our bodies. A plant has to make this on its own, however, by combining atmospheric carbon gases with hydrogen. In the process, a lot of this carbon gets stored in the roots, stem and even the soil, were microorganisms such as bacteria use it for the same purposes.

Carbon is not the only culprit, by the way; nitrogen (which is actually the most common gas in Earth's atmosphere) is also a heat-trapping gas. Unfortunately, home gardeners and a lot of farmers overdo it when using nitrogen-based fertilizers. Plants can only use a certain amount of it and the soil can only hold so much. The rest of it goes right back up into the air.

Next week, we'll talk about some practical solutions.