Table 1. The UMD-CTM Simulations With Different Sources of NOx Emissions


Simulation Name	Anthropogenic NOxa	Lightning NOxb	Period Simulated

L0	CEMS 2004	OTD/LIS (240)	May-Aug 2004
L1 (standard)	CEMS 2002, CEMS 2004 	NLDN-based (240)	May-Aug 2002, May-Aug 2004
L2 (doubled lightning)	CEMS 2004	NLDN-based (480)	May-Aug 2004
noAnthro-NAc	none	NLDN-based (240)	May-Aug 2002, May-Aug 2004
noL-NAc	CEMS 2002, CEMS 2004	none	May-Aug 2002, May-Aug 2004
no NOx SIP Call	CEMS 2002	NLDN-based (240)	May-Aug 2004

aEmission inventory used for the power plant sector for the contiguous United States (CONUS).
bObserved flash rates used to adjust the model-calculated flash rates over the CONUS; lightning NO moles produced per flash over the CONUS are in parentheses.
cNorth America is defined as Canada, the CONUS, Mexico, and the Gulf of Mexico.