Numerical modeling of lightning‐produced NO_x using an explicit lightning scheme: 1. Two‐dimensional simulation as a “proof of concept”

Abstract

[1] We use the two-dimensional (2D) version of our Storm Electrification Model to test its potential for studying lightning-produced NO x . We assume that NO production is a function of energy dissipation and calculate this value from the electric field before and after each lightning flash. We use a production rate of 9.2 Â 10 16 molecules joule À1t ogenerate the NO. Using a limited set of chemical reactions involving NO, NO 2 , and O 3 , we simulated a small storm with 10 intracloud lightning flashes produced over a 2-min span. Their energy dissipation ranged between 0.024 and 0.28 GJ. The simulation was run an additional 18 min after the cessation of lightning. Our results show that the parameterization produced NO mixing ratios internal to the cloud of the order of 10 ppbv after the most energetic flashes and 1-2 ppbv in the upwind portion of the anvil toward the end of the simulation. These mixing ratios are shown to be comparable to observations in a generic sense. Comparison with the C-shaped profiles developed by Pickering et al.[1998], also using a 2D model, show similarities, but our results are more weighted toward larger values at higher altitudes than those of Pickering et al. This may be due to differences in the length of the simulation, a lack of cloud-to-ground lightning in our work, a lack of reactive chemistry in Pickering et al., or the use by Pickering et al. of the assumption of Price et al. [1997] that intracloud flashes dissipate one tenth the energy of cloud-to-ground flashes. We show, using recent observational data and an analysis of the assumptions of Price et al., that this one tenth energy dissipation assumption is not appropriate. We conclude that our use of an explicit lightning scheme to study NO production at the process level is a viable methodology. Citation: Zhang, X., J. H. Helsdon Jr., and R. D. Farley, Numerical modeling of lightning-produced NO x using an explicit lightning scheme: 1. Two-dimensional simulation as a ''proof of concept'',

Lightning activity in Brazilian thunderstorms during TROCCINOX: implications for NO<sub>x</sub> production

“…In addition, laboratory results from Gallardo and Cooray (1996) and model simulations from Zhang et al (2003) support that IC and CG flashes are similarly energetic. On the other hand, laboratory studies by showed that LNOx depends less on energy and more on atmospheric pressure and the peak current of the flash.…”

The global lightning-induced nitrogen oxides source

“…Recently, lightning has been addressed also in numerical weather prediction models (van den Broeke et al, 2005;Mansell et al, 2007). At present only very few two-dimensional (2-D) and threedimensional (3-D) global models exist which explicitly simulate the storm electrification process with charge separation and lightning formation together with the NO x formation and the resultant tropospheric chemistry (Zhang et al, 2003b;2003c). Instead most models parameterise the LNO x source distribution directly as a function of the meteorological variables in the model.…”

“…Previous reviews of LNO x discuss theoretical, laboratory, and field studies to determine the amount of LNO x (Tuck, 1976;Drapcho et al, 1983;Borucki and Chameides, 1984;Biazar and McNider, 1995;Lawrence et al, 1995;Lee et al, 1997;Price et al, 1997b;Huntrieser et al, 1998;Bradshaw et al, 2000;, mainly by extrapolating measurements of emissions from individual lightning or thunderstorm events to the global scale (Chameides et al, 1977(Chameides et al, , 1987. Only a few papers review the determination of the global LNO x source by fitting models to observations Zhang et al, 2003b). The majority of studies since the mid1990s, as reviewed in this paper, assumed a best-estimate Published by Copernicus Publications on behalf of the European Geosciences Union.…”

“…The mean tropical tropospheric ozone column increases by about 14% (26 to 29.6 Dobson units) for an increase of the LNO x source from 3 to 6 Tg a −1 (Martin et al, 2002b), or 10% for an increase from 3 to 8 Tg a −1 (Wild, 2007). Though LNO x (for a global LNO x source of 7 Tg a −1 ) contributes only to about 5% of the total USA NO x emissions, summer lightning may play a dominant role regionally and at certain times in controlling NO x and O 3 concentrations in the middle and upper troposphere (Bond et al, 2001;Zhang et al, 2003b;Cooper et al, 2006).…”

“…The large-scale models should be able to resolve the "warm conveyor belt" of midlatitude cyclones contributing to long-distance trace species transport (Browning, 1990;Stohl et al, 2003;Huntrieser et al, 2005). CTMs are often tested in their ability to represent the transport and chemistry of species for given meteorology (Brunner et al, 2003(Brunner et al, , 2005Zhang et al, 2003b;Eyring et al, 2006;Gauss et al, 2006;Stevenson et al, 2006;van Noije et al, 2006). Relatively less attention has been given to validate the (often coarsely represented or simplified) meteorological fields and processes used in driving the transport and chemistry in the CTM.…”