Journal article
Improved modelling of soil NO x emissions in a high temperature agricultural region: role of background emissions on NO2 trend over the US
Environmental research letters, Vol.16(8), 084061
08/06/2021
DOI: 10.1088/1748-9326/ac16a3
Abstract
EPA reports a steady decline of US anthropogenic NOx emissions in 2005–2019 summers, while NO2 vertical column densities (VCDs) from the OMI satellite over large spatial domains have flattened since 2009. To better understand the contributing factors to a flattening of the OMI NO2 trends, we investigate the role of soil and lightning NOx emissions on this apparent disagreement. We improve soil NOx emissions estimates using a new observation-based temperature response, which increases the linear correlation coefficient between GEOS-Chem simulated and OMI NO2 VCDs by 0.05–0.2 over the Central US. Multivariate trend analysis reveals that soil and lightning NOx combined emissions trends change from −3.95% a−1 during 2005–2009 to 0.60% a−1 from 2009 to 2019, thereby rendering the abrupt slowdown of total NOx emissions reduction. Non-linear inter-annual variations explain 6.6% of the variance of total NOx emissions. As background emissions become relatively larger with uncertain inter-annual variations, the NO2 VCDs alone at the national scale, especially in the regions with vast rural areas, will be insufficient to discern the trend of anthropogenic emissions.
Details
- Title: Subtitle
- Improved modelling of soil NO x emissions in a high temperature agricultural region: role of background emissions on NO2 trend over the US
- Creators
- Yi Wang - The University of Iowa Department of Chemical and Biochemical Engineering, Iowa City, IA 52242, United States of AmericaCui Ge - South Coast Air Quality Management District , Diamond Bar, CA 91765, United States of AmericaLorena Castro Garcia - The University of Iowa Department of Chemical and Biochemical Engineering, Iowa City, IA 52242, United States of AmericaG Darrel Jenerette - University of California Department of Botany and Plant Sciences, Riverside, CA 92521, United States of AmericaPatty Y Oikawa - California State University Department of Earth and Environmental Sciences, East Bay, Hayward, CA 94542, United States of AmericaJun Wang - The University of Iowa Department of Chemical and Biochemical Engineering, Iowa City, IA 52242, United States of America
- Resource Type
- Journal article
- Publication Details
- Environmental research letters, Vol.16(8), 084061
- DOI
- 10.1088/1748-9326/ac16a3
- eISSN
- 1748-9326
- Publisher
- IOP Publishing
- Number of pages
- 9
- Grant note
- DEB-1656062 / National Science Foundation (http://dx.doi.org/10.13039/100000001) NA19OAR4310178 / National Oceanic and Atmospheric Administration (http://dx.doi.org/10.13039/100000192) 80NSSC19K095; NNX17AF77G / NASA Atmospheric Modeling and Analysis program 2019-67021-29227 / USDA
- Language
- English
- Date published
- 08/06/2021
- Academic Unit
- Civil and Environmental Engineering; Iowa Technology Institute; Physics and Astronomy; Chemical and Biochemical Engineering
- Record Identifier
- 9984161597302771
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