Production of lightning NO_x and its vertical distribution calculated from three‐dimensional cloud‐scale chemical transport model simulations

Abstract

[1] A three-dimensional (3-D) cloud-scale chemical transport model that includes a parameterized source of lightning NO x on the basis of observed flash rates has been used to simulate six midlatitude and subtropical thunderstorms observed during four field projects. Production per intracloud (P IC ) and cloud-to-ground (P CG ) flash is estimated by assuming various values of P IC and P CG for each storm and determining which production scenario yields NO x mixing ratios that compare most favorably with in-cloud aircraft observations. We obtain a mean P CG value of 500 moles NO (7 kg N) per flash. The results of this analysis also suggest that on average, P IC may be nearly equal to P CG , which is contrary to the common assumption that intracloud flashes are significantly less productive of NO than are cloud-to-ground flashes. This study also presents vertical profiles of the mass of lightning NO x after convection based on 3-D cloud-scale model simulations. The results suggest that following convection, a large percentage of lightning NO x remains in the middle and upper troposphere where it originated, while only a small percentage is found near the surface. The results of this work differ from profiles calculated from 2-D cloud-scale model simulations with a simpler lightning parameterization that were peaked near the surface and in the upper troposphere (referred to as a ''C-shaped'' profile). The new model results (a backward C-shaped profile) suggest that chemical transport models that assume a C-shaped vertical profile of lightning NO x mass may place too much mass near the surface and too little in the middle troposphere.

Systematic analysis of tropospheric NO<sub>2</sub> long-range transport events detected in GOME-2 satellite data

“…Schumann and Huntrieser (2007) report that approximately 5±3 TgN/a may originate from NO x emitted by lightning (LiNO x ). Ott et al (2010) show that NO x concentrations in thunderstorm clouds may be higher than 10 ppbv. They also show that only a small fraction of this LiNO x is located in the cloud top, where the sensitivity of satellite observations is high.…”

The NASA Lightning Nitrogen Oxides Model (LNOM): Application to air quality modeling

“…There has been considerable variability in the estimates of lightning NOx production per flash; see for example the summary table in Labrador et al (2005), the review paper by , and the studies by DeCaria et al (2000DeCaria et al ( , 2005, Beirle et al (2004Beirle et al ( , 2010, Langford et al (2004), Rahman et al (2007), Huntrieser et al (2008), Jourdain et al (2010), Ott et al (2010), and Peterson and Beasley (2011). The variability in these estimates is linked to the differences in the estimation methods employed, and the natural variability of lightning.…”

Steps towards a mechanistic model of global soil nitric oxide emissions: implementation and space based-constraints

“…Flash rates are scaled based for each grid box on monthly average rates from the Lightning Imaging Sensor and Optical Transient Detector satellite instruments (OTD/LIS) (Sauvage et al, 2007;Murray et al, 2012). NO x yield per flash is 125 mol in the tropics and 500 mol at northern mid-latitudes (north of 30 • N) (Hudman et al, 2007) with vertical NO x emission profiles from Ott et al (2010).…”