Who would have imagined the leap from national parks to cow farts was so small! Kath is right concerning the UN report. You can find it at: http://www.un.org/apps/news/story.asp?NewsID=20772&Cr=global&Cr1=environment Of course, not only do cows produce problems via their discharges, but also as land is cleared of trees to create more grazing areas. That process destroys valuable carbon sinks. Still, I think the NPS is right in its decision to try to quantify, at least in one park, how much Greenhouse Gas emissions its facilities and operations produce. Only by knowing the sources and the quantity can we work to minimize those outputs.

Kath, I don't think it's quite as easy as you make it out. Perhaps I'm wrong, but there would seem to be a wide variety of GHG sources to be considered, ranging from passenger cars, pickup trucks, delivery trucks, buses, late-model vehicles, older ones that pollute more. Also to be factored in, I would think, are traffic patterns. Then, too, there are electrical and natural gas consumptions that are unique to each park, campfires, forest fires, heat sinks, carbon sinks and on and on. And let's not forget sustainable development practices that can be implemented. What does a park do? In some cases it can replace its vehicle fleet with cleaner burning rigs. It can consider mass transit programs. It can look into solar and wind energy to supplement electrical demand. It can replace less energy efficient facilities. But without studying and quantifying exactly where the GHG generation is based, it's hard to come up with a logical and effective solution. Way back in 2001 the DOI and DOE announced the "Green Energy Parks" program, which was intended to showcase how parks can be made more energy efficient and with less of an impact on resources. You can read about it here: http://www.nps.gov/renew/mou.htm It's good to see the parks moving forward with this initiative.