EPA greenhouse gas emissions inventory data for the northeast for the years 2008 and 2011
(src: http://www.epa.gov/ttn/chief/eiinformation.html)

fips: A five-digit number indicating the U.S. county and state
stfips: A two digit number representing the U.S. state
ctyfips: A three digit number representing the state county
state_abbr: A two letter string representing U.S. state
county_name: County name
EI_sector: The type of pollution source
pollutant_code: The greenhouse gas type code
pollutant_name: The greenhouse gas type name
emissions: Emissions in units defined in the uom column
uom: emission units (should be in Ton/year)
inventory_year: inventory year