For carbon emissions:

Go to World Bank Carbon Finance Web Site

Go to Carbon Market Data. The World Emissions Trading Scheme (ETS) Database and EU ETS Companies Database are free (registration required).

Go to International Emissions Trading Association

Go to European Energy Exchange (free registration required)

For sulfur dioxide emissions:

Go to EPA Auction of SO2 Allowances

Go to Bloomberg available in the Margolis Market Information Lab(MIL) at the Business Instructional Facility(BIF). For futures contract pricing for sulfur dioxide emissions; type YOA Comdty.