We're so happy (OK, more like ecstatic) about the recent wave of people, companies and organizations "going green." Everywhere you look these days, you see hybrid cars, solar panels, recycling bins, and so on. And we were really thrilled to learn about the U.S. Environmental Protection Agency's new project using Google Earth.

The EPA has created an amazing KML file that tracks air emission sources. That means Google Earth users can now track air quality, near and far, from the comfort of their computer screens.

The layer also makes it possible to see which companies are generating air pollutants at the highest rates. Select a given location and view placemarks of all of the companies in the area. Tilt the earth until you're at ground level and check out the collection of placemarks; they vary in height based on pollutants emitted at their particular location. Click on a company of interest to read about their eco-history.

We hope people make good use of this great new tool, whether it be to simply discover the air quality in different areas around the world or to encourage companies to engage in more environmentally friendly practices. To find out how to get started, take a look at this informative EPA page -- it couldn't be simpler.

Update: The EPA has actually created not one but two informative KML files. In addition to a layer that tracks air emission sources, the EPA has created a KML file that provides real-time air quality information. This tool displays the most current air quality conditions by city, updated hourly with data taken from the AIRNow database. Check out their website, which includes instructions for using this informative tool.