NOX FROM LIGHTNING .2. CONSTRAINTS FROM THE GLOBAL ATMOSPHERIC ELECTRIC-CIRCUIT

The global atmospheric electric circuit can be used to constrain the t otal amount of NOx produced by lightning (LNO(x)). Since the global at mospheric electric circuit is regulated by global thunderstorm activit y and, more specifically, global lightning currents, we use the global electric circuit to quantify and place limits on the total amount of energy available from lightning. Using a production rate of 10 x 10(16 ) molecules NO/J, we have calculated the global LNO(x) production on m onthly, annual, and interannual timescales from 1983 to 1991. The 8-ye ar mean production rate is found to be 13.2 Tg N/yr and agrees with th e independent estimate derived in part 1 of this study (12.2 Tg N/yr), which is based on lightning physics and global lightning distribution s. After considering the various uncertainties in these calculations, we conclude that the annual production rate of NOx from lightning cann ot be less than 5 nor more than 25 Tg N/yr.