The effects of lightning-produced NOx and its vertical distribution on atmospheric chemistry: sensitivity simulations with MATCH-MPIC
Other literature type
Labrador, L. J.
Lawrence, M. G.
The impact of different assumptions concerning the source magnitude as well as
the vertical placement of lightning-produced nitrogen oxides is studied using
the global chemistry transport model MATCH-MPIC. The responses of NO<sub>x</sub>,
O<sub>3</sub>, OH, HNO<sub>3</sub> and peroxyacetyl-nitrate (PAN) are investigated. A marked
sensitivity to both parameters is found. NO<sub>x</sub> burdens globally can be
enhanced by up to 100% depending on the vertical placement and source magnitude
strength. In all cases, the largest enhancements occur in the tropical upper
troposphere, where lifetimes of most trace gases are longer and where they thus
become more susceptible to long-range transport by large-scale circulation
patterns. Comparison with observations indicate that 0 and 20 Tg(N)/yr
production rates of NO<sub>x</sub> from lightning are too low and too
high, respectively. However, no single intermediate production rate
or vertical distribution can be singled out as best fitting the observations,
due to the large scatter in the datasets. This underscores the need for
further measurement campaigns in key regions, such as the tropical continents.