At Google, we make engineering decisions based on careful data collection and analysis. So when I tried, on my own, to understand deeper the issues of the global climate change, I realized that while general information is widely available, it's not easy to find detailed data. What exactly is my individual impact? How much greenhouse gases do people produce during various activities? How exactly do different localities compare to each other?

While several reports and inventories of human fossil fuel CO2 emissions in the US already exist, the most comprehensive one that I know of was produced by Project Vulcan, a team of scientists lead by Dr Kevin Gurney, an assistant professor of Earth and atmospheric sciences at Purdue University. Vulcan data represent detailed emissions for all 50 US states in 2002. Dr Gurney presented the most recent results of his work this week at a meeting of North American Carbon Program.

The results produced by Project Vulcan are publicly available, but they are not easy to analyze for a non-scientist, so during my 20% time at Google I have created dynamic maps of the Vulcan data, broken down by sector. You can view the maps in your browser if you have Google Earth plugin installed, or you can load the data in Google Earth itself.

By looking at the data on a map, you can see for yourself what US states and counties have the highest and the lowest emission rates - absolute or per capita. You can notice where people burn more gasoline for driving, or where they use more fuel for heating and cooling their homes and businesses.

Here's a video with a Google Earth flythrough and a commentary explaining various data layers.

Finally, I would like to thank fellow Googlers Christiaan Adams, Frank Dachille, and Jake Knapp, and other individuals who provided feedback on this map!