We emit greenhouse gases both directly and indirectly. Our direct (Scope 1) emissions come from our industrial businesses, including the use of natural gas and diesel, and fugitive emissions from coal mining. Our main source of indirect (Scope 2) emissions is electricity used by our operations. We also estimate our Scope 3 emissions, which are other indirect emissions that occur as a result of our operations (e.g. employee air travel), but are not controlled by us.