One solution being discussed to curb greenhouse gas emissions is carbon taxes or, in the case of imported goods, carbon tariffs. The idea is to make major polluters pay in order to induce them to go carbon neutral or to have them fund projects and programmes to offset their GHG emissions.
A common criticism of carbon tariffs is determining just what is the carbon footprint of any particular commodity. Now an American satellite mapping initiative has shown there are ways of monitoring carbon emitters from space. Check out this video.