{"database":"biostudies-literature","file_versions":[],"scores":null,"additional":{"submitter":["Sarwar G"],"funding":["Natural Environment Research Council","Intramural EPA"],"pagination":["170406"],"full_dataset_link":["https://www.ebi.ac.uk/biostudies/studies/S-EPMC10922608"],"repository":["biostudies-literature"],"omics_type":["Unknown"],"volume":["917"],"pubmed_abstract":["We use the Community Multiscale Air Quality (CMAQv5.4) model to examine the potential impact of particulate nitrate (pNO<sub>3</sub><sup>-</sup>) photolysis on air quality over the Northern Hemisphere. We estimate the photolysis frequency of pNO<sub>3</sub><sup>-</sup> by scaling the photolysis frequency of nitric acid (HNO<sub>3</sub>) with an enhancement factor that varies between 10 and 100 depending on pNO<sub>3</sub><sup>-</sup> and sea-salt aerosol concentrations and then perform CMAQ simulations without and with pNO<sub>3</sub><sup>-</sup> photolysis to quantify the range of impacts on tropospheric composition. The photolysis of pNO<sub>3</sub><sup>-</sup> produces gaseous nitrous acid (HONO) and nitrogen dioxide (NO<sub>2</sub>) over seawater thereby increasing atmospheric HONO and NO<sub>2</sub> mixing ratios. HONO subsequently undergoes photolysis, producing hydroxyl radicals (OH). The increase in NO<sub>2</sub> and OH alters atmospheric chemistry and enhances the atmospheric ozone (O<sub>3</sub>) mixing ratio over seawater, which is subsequently transported to downwind continental regions. Seasonal mean model O<sub>3</sub> vertical column densities without pNO<sub>3</sub><sup>-</sup> photolysis are lower than the Ozone Monitoring Instrument (OMI) retrievals, while the column densities with the pNO<sub>3</sub><sup>-</sup> photolysis agree better with the OMI retrievals of tropospheric O<sub>3</sub> burden. We compare model O<sub>3</sub> mixing ratios with available surface observed data from the U.S., Japan, the Tropospheric Ozone Assessment Report - Phase II, and OpenAQ; and find that the model without pNO<sub>3</sub><sup>-</sup> photolysis underestimates the observed data in winter and spring seasons and the model with pNO<sub>3</sub><sup>-</sup> photolysis improves the comparison in both seasons, largely rectifying the pronounced underestimation in spring. Compared to measurements from the western U.S., model O<sub>3</sub> mixing ratios with pNO<sub>3</sub><sup>-</sup> photolysis agree better with observed data in all months due to the persistent underestimation of O<sub>3</sub> without pNO<sub>3</sub><sup>-</sup> photolysis. Compared to the ozonesonde measurements, model O<sub>3</sub> mixing ratios with pNO<sub>3</sub><sup>-</sup> photolysis also agree better with observed data than the model O<sub>3</sub> without pNO<sub>3</sub><sup>-</sup> photolysis."],"journal":["The Science of the total environment"],"pubmed_title":["Impact of particulate nitrate photolysis on air quality over the Northern Hemisphere."],"pmcid":["PMC10922608"],"funding_grant_id":["EPA999999","NE/S000518/1","NE/N009983/1"],"pubmed_authors":["Henderson BH","Gilliam R","Callaghan AB","Carpenter LJ","Lee J","Sarwar G","Hogrefe C","Mathur R"],"additional_accession":[]},"is_claimable":false,"name":"Impact of particulate nitrate photolysis on air quality over the Northern Hemisphere.","description":"We use the Community Multiscale Air Quality (CMAQv5.4) model to examine the potential impact of particulate nitrate (pNO<sub>3</sub><sup>-</sup>) photolysis on air quality over the Northern Hemisphere. We estimate the photolysis frequency of pNO<sub>3</sub><sup>-</sup> by scaling the photolysis frequency of nitric acid (HNO<sub>3</sub>) with an enhancement factor that varies between 10 and 100 depending on pNO<sub>3</sub><sup>-</sup> and sea-salt aerosol concentrations and then perform CMAQ simulations without and with pNO<sub>3</sub><sup>-</sup> photolysis to quantify the range of impacts on tropospheric composition. The photolysis of pNO<sub>3</sub><sup>-</sup> produces gaseous nitrous acid (HONO) and nitrogen dioxide (NO<sub>2</sub>) over seawater thereby increasing atmospheric HONO and NO<sub>2</sub> mixing ratios. HONO subsequently undergoes photolysis, producing hydroxyl radicals (OH). The increase in NO<sub>2</sub> and OH alters atmospheric chemistry and enhances the atmospheric ozone (O<sub>3</sub>) mixing ratio over seawater, which is subsequently transported to downwind continental regions. Seasonal mean model O<sub>3</sub> vertical column densities without pNO<sub>3</sub><sup>-</sup> photolysis are lower than the Ozone Monitoring Instrument (OMI) retrievals, while the column densities with the pNO<sub>3</sub><sup>-</sup> photolysis agree better with the OMI retrievals of tropospheric O<sub>3</sub> burden. We compare model O<sub>3</sub> mixing ratios with available surface observed data from the U.S., Japan, the Tropospheric Ozone Assessment Report - Phase II, and OpenAQ; and find that the model without pNO<sub>3</sub><sup>-</sup> photolysis underestimates the observed data in winter and spring seasons and the model with pNO<sub>3</sub><sup>-</sup> photolysis improves the comparison in both seasons, largely rectifying the pronounced underestimation in spring. Compared to measurements from the western U.S., model O<sub>3</sub> mixing ratios with pNO<sub>3</sub><sup>-</sup> photolysis agree better with observed data in all months due to the persistent underestimation of O<sub>3</sub> without pNO<sub>3</sub><sup>-</sup> photolysis. Compared to the ozonesonde measurements, model O<sub>3</sub> mixing ratios with pNO<sub>3</sub><sup>-</sup> photolysis also agree better with observed data than the model O<sub>3</sub> without pNO<sub>3</sub><sup>-</sup> photolysis.","dates":{"release":"2024-01-01T00:00:00Z","publication":"2024 Mar","modification":"2025-04-05T12:39:11.952Z","creation":"2025-04-05T12:39:11.952Z"},"accession":"S-EPMC10922608","cross_references":{"pubmed":["38281631"],"doi":["10.1016/j.scitotenv.2024.170406"]}}