Open AccessUnderestimated Ammonia Emissions from Road Vehicles
Author(s) -
Naomi J. Farren,
Jack Davison,
Rebecca Rose,
Rebecca Wagner,
David C. Carslaw
Publication year - 2020
Publication title -
environmental science and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.851
H-Index - 397
eISSN - 1520-5851
pISSN - 0013-936X
DOI - 10.1021/acs.est.0c05839
Subject(s) - gasoline , environmental science , emission inventory , ammonia , environmental engineering , meteorology , air quality index , engineering , waste management , geography , chemistry , organic chemistry
In this study, we use comprehensive vehicle emission remote sensing measurements of over 230,000 passenger cars to estimate total UK ammonia (NH 3 ) emissions. Estimates are made using "top-down" and "bottom-up" methods that demonstrate good agreement to within 1.1% for total fuel consumed or CO 2 emitted. A central component of this study is the comprehensive nature of the bottom-up emission estimates that combine highly detailed remote sensing emission data with over 4000 km of 1 Hz real driving data. Total annual UK NH 3 emissions from gasoline passenger cars are estimated to be 7.8 ± 0.3 kt from the bottom-up estimate compared with 3.0 ± 1.7 kt reported by the UK national inventory. An important conclusion from the analysis is that both methodologies confirm that gasoline passenger car NH 3 emissions are underestimated by a factor of about 2.6 compared with the 2018 UK National Atmospheric Emissions Inventory. Furthermore, we find that inventory estimates of urban emissions of NH 3 for passenger cars are underestimated by a factor of 17.