The EPA just released new data showing that greenhouse gas emissions in the United States decreased. The report, which is called the Greenhouse Gas Inventory Report, was submitted to the United Nations.

This report covered the years 2007 through 2008, so it takes a while for this report to be compiled. It’s fairly obvious that the housing crash and the oil price spike had a lot to do with the drop. The EPA does mention another factor, the summer of 2008 was colder than usual so there was less heating oil used. I didn’t notice any unusually cold weather that summer, but I did notice that California gasoline prices rose above $4 a gallon. California gas prices are on the rise once again, up to the $3.30 range for now, even with a much weaker economy. The unemployment numbers for the state came out yesterday and were reported at 12.6 percent. A lot of drivers are off the road now, leading to other benefits such as less car crashes, less cars idling in traffic and wasting fuel, and less wear and tear on the road. Unfortunately, this is all due to the state’s economic problems, although it’s likely that greenhouse gas emissions in the state of California dropped in 2007 through 2008 as well.

The greenhouse gas emissions report mentions a few things I didn’t know before. Rainfall affects the amount of petroleum required because of hydro plants. Since the dams that generate electricity require water flowing down rivers to power their generators, reduced storms and rainfall require utilities to burn extra fuel to make up the difference. The EPA’s table in the report also shows that commercial and residential carbon dioxide emissions actually increased, although this was overshadowed by a large drop in manufacturing carbon dioxide emissions so the overall amount of emissions still declined. There was also a significant regional effect: Carbon dioxide emissions in the US territories dropped sharply, from 49.1 to 42.5 teragrams of carbon dioxide equivalents according to the EPA. That’s about five times the percentage drop for the mainland United States.