Modeling lightning-NO<sub><i>x</i></sub> chemistry on a sub-grid scale in a global chemical transport model

Abstract

Abstract. For the first time, a plume-in-grid approach is implemented in a chemical transport model (CTM) to parameterize the effects of the nonlinear reactions occurring within high concentrated NO x plumes from lightning NO x emissions (LNO x ) in the upper troposphere. It is characterized by a set of parameters including the plume lifetime, the effective reaction rate constant related to NO x -O 3 chemical interactions, and the fractions of NO x conversion into HNO 3 within the plume. Parameter estimates were made using the Dynamical Simple Model of Atmospheric Chemical Complexity (DSMACC) box model, simple plume dispersion simulations, and the 3-D Meso-NH (non-hydrostatic mesoscale atmospheric model). In order to assess the impact of the LNO x plume approach on the NO x and O 3 distributions on a large scale, simulations for the year 2006 were performed using the GEOS-Chem global model with a horizontal resolution of 2 • × 2.5 • . The implementation of the LNO x parameterization implies an NO x and O 3 decrease on a large scale over the region characterized by a strong lightning activity (up to 25 and 8 %, respectively, over central Africa in July) and a relative increase downwind of LNO x emissions (up to 18 and 2 % for NO x and O 3 , respectively, in July). The calculated variability in NO x and O 3 mixing ratios around the mean value according to the known uncertainties in the parameter estimates is at a maximum over continental tropical regions with NO [−1.18, +1.93] ppb, in July, mainly depending on the determination of the diffusion properties of the atmosphere and the initial NO mixing ratio injected by lightning. This approach allows us (i) to reproduce a more realistic lightning NO x chemistry leading to better NO x and O 3 distributions on the large scale and (ii) to focus on other improvements to reduce remaining uncertainties from processes related to NO x chemistry in CTM.

Global high-resolution simulations of tropospheric nitrogen dioxide using CHASER V4.0

“…An important advantage of global high-resolution models over regional models and two-way nesting systems is the ability to simulate NO 2 concentration fields at high resolutions over the entire globe across urban, biomass burning, and remote regions in a consistent framework. Even over remote regions, a highresolution simulation has the potential to improve model performance through considering the effects of nonlinear chemistry in highly concentrated NO x plumes emitted from ships and lightning (Charlton-Perez et al, 2009;Vinken et al, 2011;Gressent et al, 2016). These NO x emission sources in remote regions have significant impacts on climate and air quality (Eyring et al, 2010;Holmes et al, 2014;Banerjee et al, 2014;Finney et al, 2016).…”

The IAGOS NO<sub><i>x</i></sub> instrument – design, operation and first results from deployment aboard passenger aircraft

“…Aircraft campaigns conducted in the past have made considerable progress in improving the estimate of the emissions of aviation (Schumann and Huntrieser, 2007;Lee et al, 2010;Wasiuk et al, 2016); in improving the estimate of LNO x emissions over different regions, summarized by Gressent et al (2016); and in increasing knowledge of deep convectively lifted pollutants and their burden to ozone chemistry (Huntrieser et al, 2016). However, these and other research aircraft campaigns lack the statistical robustness of comprehensive seasonal and geographical coverage of the UTLS region.…”

“…Parameterization of natural NO x emissions by lightning still has large uncertainty in global chemical transport models (e.g., Gressent et al, 2016). Brunner et al (2005) and Prather et al (2017) concluded that a better description of emissions, chemistry and sinks of NO x (and other key species) is needed to improve chemistry in the UTLS region in global chemistry models.…”

“…In the upper troposphere and lowermost stratosphere (UTLS), emissions from cruising passenger aircraft form another important source of NO x , with its source strength being determined from civil aviation traffic data and specific emission factors (Emmons et al, 1997;Rohrer et al, 1997;Schumann and Huntrieser, 2007;Ziereis et al, 2000;Gressent et al, 2016). Aircraft campaigns conducted in the past have made considerable progress in improving the estimate of the emissions of aviation (Schumann and Huntrieser, 2007;Lee et al, 2010;Wasiuk et al, 2016); in improving the estimate of LNO x emissions over different regions, summarized by Gressent et al (2016); and in increasing knowledge of deep convectively lifted pollutants and their burden to ozone chemistry (Huntrieser et al, 2016).…”

The IAGOS NO<sub>x</sub> Instrument – Design, Operation and First Results from Deployment aboard Passenger Aircraft

“…10 Most relevant natural sources of NO x are lightning (LNO x ), biomass burning, soil emissions, and anthropogenic sources, such as power generation, road transportation and aviation. The current knowledge of the global distribution of NO x and its emission estimates is based mostly on specific aircraft missions (Emmons et al, 1997;Rohrer et al, 1997;Schumann and Huntrieser, 2007;Ziereis et al, 2000;Gressent et al, 2016), on surface 15 monitoring stations (Aerosols, Clouds and Trace gases Research Infrastructure (ACTRIS); www.actris.eu), satellite measurements (Fishman et al, 2008;de Laat et al, 2014;Duncan et al, 2015) and model simulations (Ehhalt et al, 1992;Emmons et al, 1997).…”