Vertical distributions of lightning NOx for use in regional and global chemical transport models

作者：Kenneth Pickering, Yansen Wang, Wei‐Kuo Tao, Colin Price, Jean‐François Müller · 发表于：Journal of Geophysical Research Atmospheres · 年份：1998 · DOI：10.1029/98jd02651 · 被引用次数：464 · 研究领域：Atmospheric chemistry and aerosols、Atmospheric and Environmental Gas Dynamics、Atmospheric Ozone and Climate

We have constructed profiles of lightning NOχ mass distribution for use in specifying the effective lightning NOχ source in global and regional chemical transport models. The profiles have been estimated for midlatitude continental, tropical continental, and tropical marine regimes based on profiles computed for individual storms in each regime. In order to construct these profiles we have developed a parameterization for lightning occurrence, lightning type, flash placement, and NOχ production in a cloud‐scale tracer transport model using variables computed in the two‐dimensional Goddard Cumulus Ensemble (GCE) model. Wind fields from the GCE model are used to redistribute the lightning NOχ throughout the duration of the storm. Our method produces reasonable results in terms of computed flash rates and NOχ mixing ratios compared with observations. The profiles for each storm are computed by integrating the lightning NOχ mass across the cloud model domain for each model layer at the end of the storm. The results for all three regimes show a maximum in the mass profile in the upper troposphere, usually within 2–4 km of the tropopause. Downdrafts appear to be the strongest in the simulated midlatitude continental systems, evidenced by substantial lightning NOχ mass (up to 23%) in the lowest kilometer. Tropical systems, particularly those over marine areas, tended to have a greater fraction of intracloud flashes and weaker downdrafts, causing only minor amounts of NOχ to remain i...