Development of a self‐consistent lightning NO x simulation in large‐scale 3‐D models

We seek to develop a self‐consistent representation of lightning NO x (LNO x ) simulation in a large‐scale 3‐D model. Lightning flash rates are parameterized functions of meteorological variables related to convection. We examine a suite of such variables and find that convective available potential energy and cloud top height give the best estimates compared to July 2010 observations from ground‐based lightning observation networks. Previous models often use lightning NO x vertical profiles derived from cloud‐resolving model simulations. An implicit assumption of such an approach is that the postconvection lightning NO x vertical distribution is the same for all deep convection, regardless of geographic location, time of year, or meteorological environment. Detailed observations of the lightning channel segment altitude distribution derived from the NASA Lightning Nitrogen Oxides Model can be used to obtain the LNO x emission profile. Coupling such a profile with model convective transport leads to a more self‐consistent lightning distribution compared to using prescribed postconvection profiles. We find that convective redistribution appears to be a more important factor than preconvection LNO x profile selection, providing another reason for linking the strength of convective transport to LNO x distribution.