Significant ground-level ozone attributed to lightning-induced nitrogen oxides during summertime over the Mountain West States.

Autor: Kang D; Center for Environmental Measurement and Modeling, U.S. Environmental Protection Agency, Research Triangle Park, NC, USA., Mathur R; Center for Environmental Measurement and Modeling, U.S. Environmental Protection Agency, Research Triangle Park, NC, USA., Pouliot GA; Center for Environmental Measurement and Modeling, U.S. Environmental Protection Agency, Research Triangle Park, NC, USA., Gilliam RC; Center for Environmental Measurement and Modeling, U.S. Environmental Protection Agency, Research Triangle Park, NC, USA., Wong DC; Center for Environmental Measurement and Modeling, U.S. Environmental Protection Agency, Research Triangle Park, NC, USA.
Jazyk: angličtina
Zdroj: NPJ climate and atmospheric science [NPJ Clim Atmos Sci] 2020 Jan 30; Vol. 3, pp. 6.
DOI: 10.1038/s41612-020-0108-2
Abstrakt: Using lightning flash data from the National Lightning Detection Network with an updated lightning nitrogen oxides (NO x ) emission estimation algorithm in the Community Multiscale Air Quality (CMAQ) model, we estimate the hourly variations in lightning NO x emissions for the summer of 2011 and simulate its impact on distributions of tropospheric ozone (O 3 ) across the continental United States. We find that typical summer-time lightning activity across the U.S. Mountain West States (MWS) injects NO x emissions comparable to those from anthropogenic sources into the troposphere over the region. Comparison of two model simulation cases with and without lightning NO x emissions show that significant amount of ground-level O 3 in the MWS during the summer can be attributed to the lightning NO X emissions. The simulated surface-level O 3 from a model configuration incorporating lightning NO x emissions showed better agreement with the observed values than the model configuration without lightning NO x emissions. The time periods of significant reduction in bias in simulated O 3 between these two cases strongly correlate with the time periods when lightning activity occurred in the region. The inclusion of lightning NO x increased daily maximum 8 h O 3 by up to 17 ppb and improved model performance relative to measured surface O 3 mixing ratios in the MWS region. Analysis of model results in conjunction with lidar measurements at Boulder, Colorado during July 2014 corroborated similar impacts of lightning NO x emissions on O 3 emissions estimated for other summers is comparable to the 2011 air quality. The magnitude of lightning NO x estimates suggesting that summertime surface-level O 3 levels in the MWS region could be significantly influenced by lightning NO x .
Competing Interests: COMPETING INTERESTS The authors declare no competing interests.
Databáze: MEDLINE