A real-time, emissions reporting system, for an internal combustion engine mounted on a mobile apparatus, comprising:
- flow determination means, mounted for travel with said mobile apparatus and operative during movement of said mobile apparatus, for determining flow rate of exhaust gas of said mobile apparatus, during the movement;
- a gas analyzer for detecting concentration of each of plurality of gaseous pollutants within the exhaust gas;
- and
- calculating means for calculating and reporting mass flow rates for the gaseous pollutants in real-time based on the determined flow rate of the exhaust gas and on the detected concentrations.