Professor William Bloss PhD

William Bloss

School of Geography, Earth and Environmental Sciences
Professor of Atmospheric Science
Head of College of Life & Environmental Sciences

Contact details

School of Geography, Earth and Environmental Sciences
University of Birmingham
B15 2TT

William Bloss is an atmospheric scientist, specialising in air pollution and atmospheric chemistry.  His research applies a combination of laboratory studies, field measurements and numerical models to understand the causes of poor air quality, and support development of effective policy measures to protect human and environmental health.  Recent work has ranged from Clean Air Science for the West Midlands (WM-Air) to identification of air pollution sources in Delhi and Beijing.  


  • PhD Atmospheric Chemistry - University of Cambridge
  • BA Natural Sciences (Chemistry) - University of Cambridge


William (Bill) Bloss completed his undergraduate degree and PhD at the University of Cambridge, the latter concerning laboratory studies of atmospheric halogen oxide reactions.  He then worked as a Caltech Postdoctoral Scholar at the NASA Jet Propulsion Laboratory, studying stratospheric ozone depletion, and as a Research Fellow and then Lecturer at the University of Leeds, where he worked on field measurements of atmospheric chemistry in the UK, Europe and Antarctica.

He moved to the School of Geography, Earth & Environmental Sciences at the University of Birmingham in 2007.  His research determines the causes of poor air quality, and supports development of effective policy measures to protect human and environmental health.  Recent work has ranged from Clean Air Science for the West Midlands (WM-Air) to identification of air pollution sources in Delhi and Beijing.


BSc Environmental Sciences

MSc Air Pollution Management and Control

Postgraduate supervision

Please contact me if you are interested in studying for a PhD with the group. I'm happy to discuss ideas for PhD research projects and applications for funded fellowship schemes, but please be aware we do not have funding other than for openly advertised positions. For more information see my personal research pages at :


Atmospheric processing affects the current and future composition of our air, with impacts upon human and environmental health, air quality and climate.  My research group addresses areas of atmospheric chemistry and clean air science, including

- Understanding the sources and transformations of air pollutants in the urban atmosphere, ranging from trends in the UK to developing megacities such as Delhi

- Quantifying the sources and sinks for atmospheric oxidants: impacts from processes such as new reactive nitrogen emissions and particulate-mediated renoxification

- Applying air pollution science to improve local and regional air quality policy measures

Our work combines atmospheric field measurements, simulation chamber and laboratory studies and numerical modelling approaches.  Fundamental understanding of the atmospheric chemical system is placed in an applied context: working with partners to apply clean air science for improved human and environmental health.

See also my personal research pages and the WM-Air Project

Other activities

  • Clean Air Advisory Panel for Wales
  • Strategic Advisory Board, RESAS Scotland
  • Royal Society of Chemistry: CChem, FRSC
  • RSC Environmental Chemistry Group (Chair, 2012 – 2014)


Recent publications


Hall, J, Zhong, J, Jowett, S, Mazzeo, A, Thomas, GN, Bryson, JR, Dewar, S, Inglis, N, Wolstencroft, M, Muller, C, Bloss, W, Harrison, R & Bartington, S 2024, 'Regional Impact Assessment of Air Quality Improvement: The Air Quality Lifecourse Assessment Tool (AQ-LAT) for the West Midlands Combined Authority (WMCA)', Environmental Pollution.

Zhong, J, Stocker, J, Cai, X, Harrison, RM & Bloss, WJ 2024, 'Street-scale air quality modelling over the West Midlands, United Kingdom: Effect of idealised traffic reduction scenarios', Urban Climate, vol. 55, 101961.

Liu, B, Bryson, JR, Sevinc, D, Cole, M, Elliott, R, Bartington, S, Bloss, W & Shi, Z 2023, 'Assessing the Impacts of Birmingham’s Clean Air Zone on Air Quality: Estimates from a Machine Learning and Synthetic Control Approach', Environmental and Resource Economics, vol. 86, no. 1-2, pp. 203-231.,

Cho, C, Fuchs, H, Hofzumahaus, A, Holland, F, Bloss, WJ, Bohn, B, Dorn, HP, Glowania, M, Hohaus, T, Liu, L, Monks, PS, Niether, D, Rohrer, F, Sommariva, R, Tan, Z, Tillmann, R, Kiendler-Scharr, A, Wahner, A & Novelli, A 2023, 'Experimental chemical budgets of OH, HO2, and RO2 radicals in rural air in western Germany during the JULIAC campaign 2019', Atmospheric Chemistry and Physics, vol. 23, no. 3, pp. 2003-2033.

Molden, N, Hemming, C, Leach, F, Levine, JG, Ropkins, K & Bloss, W 2023, 'Exposures to Particles and Volatile Organic Compounds across Multiple Transportation Modes', Sustainability (Switzerland), vol. 15, no. 5, 4005.

Andersen, ST, Carpenter, LJ, Reed, C, Lee, JD, Chance, R, Sherwen, T, Vaughan, AR, Stewart, J, Edwards, PM, Bloss, WJ, Sommariva, R, Crilley, LR, Nott, GJ, Neves, L, Read, K, Heard, DE, Seakins, PW, Whalley, LK, Boustead, GA, Fleming, LT, Stone, D & Fomba, KW 2023, 'Extensive field evidence for the release of HONO from the photolysis of nitrate aerosols', Science Advances, vol. 9, no. 3, eadd6266.

Nelson, BS, Bryant, DJ, Alam, MS, Sommariva, R, Bloss, WJ, Newland, MJ, Drysdale, WS, Vaughan, AR, Acton, WJF, Hewitt, CN, Crilley, LR, Swift, SJ, Edwards, PM, Lewis, AC, Langford, B, Nemitz, E, Shivani, Gadi, R, Gurjar, BR, Heard, DE, Whalley, LK, Şahin, UA, Beddows, DCS, Hopkins, JR, Lee, JD, Rickard, AR & Hamilton, JF 2023, 'Extreme Concentrations of Nitric Oxide Control Daytime Oxidation and Quench Nocturnal Oxidation Chemistry in Delhi during Highly Polluted Episodes', Environmental Science and Technology Letters, vol. 10, no. 6, pp. 520-527.

Sommariva, R, Alam, MS, Crilley, LR, Rooney, DJ, Bloss, WJ, Fomba, KW, Andersen, ST & Carpenter, LJ 2023, 'Factors Influencing the Formation of Nitrous Acid from Photolysis of Particulate Nitrate', The Journal of Physical Chemistry A, vol. 127, no. 44, pp. 9302-9310.

Dyson, JE, Whalley, LK, Slater, EJ, Woodward-Massey, R, Ye, C, Lee, JD, Squires, F, Hopkins, JR, Dunmore, RE, Shaw, M, Hamilton, JF, Lewis, AC, Worrall, SD, Bacak, A, Mehra, A, Bannan, TJ, Coe, H, Percival, CJ, Ouyang, B, Hewitt, CN, Jones, RL, Crilley, LR, Kramer, LJ, Acton, WJF, Bloss, WJ, Saksakulkrai, S, Xu, J, Shi, Z, Harrison, RM, Kotthaus, S, Grimmond, S, Sun, Y, Xu, W, Yue, S, Wei, L, Fu, P, Wang, X, Arnold, SR & Heard, DE 2023, 'Impact of HO2 aerosol uptake on radical levels and O3 production during summertime in Beijing', Atmospheric Chemistry and Physics, vol. 23, no. 10, pp. 5679-5697.

Zhong, J, Hodgson, JR, Bloss, W & Shi, Z 2023, 'Impacts of net zero policies on air quality in a metropolitan area of the United Kingdom: Towards world health organization air quality guidelines', Environmental Research, vol. 236, 116704.

Matthaios, VN, Harrison, RM, Koutrakis, P & Bloss, WJ 2023, 'In-vehicle exposure to NO2 and PM2.5: A comprehensive assessment of controlling parameters and reduction strategies to minimise personal exposure', Science of the Total Environment, vol. 900, 165537.

Zhong, J, Harrison, RM, Bloss, WJ, Visschedijk, A & Denier van der Gon, HAC 2023, 'Modelling the dispersion of particle number concentrations in the West Midlands, UK using the ADMS-Urban model', Environment International, vol. 181, 108273.

Matthaios, VN, Rooney, D, Harrison, RM, Koutrakis, P & Bloss, WJ 2023, 'NO2 levels inside vehicle cabins with pollen and activated carbon filters: A real world targeted intervention to estimate NO2 exposure reduction potential', Science of the Total Environment, vol. 860, 160395.

Conference contribution

Zhong, J, Hood, C, Johnson, K, Stocker, J, Handley, J, Wolstencroft, M, Mazzeo, A, Cai, X & Bloss, WJ 2023, Modelling Street-Scale Resolution Air Quality for the West Midlands (UK) Using the ADMS-Urban RML System. in C Mensink & O Jorba (eds), Air Pollution Modeling and its Application XXVIII. 1 edn, Springer Proceedings in Complexity, Springer, pp. 77-82, ITM 2021, Barcelona, Spain, 18/10/21.

Other report

Baldo, C, Zhong, J, Hall, J, Muller, C, Bartington, S & Bloss, W 2023, New Air Quality Targets & Interim Goals for Fine Particulate Matter – PM2.5: Implications for the West Midlands. University of Birmingham.

View all publications in research portal


Air Quality & Human Health

Sources of air pollutants: Traffic emissions

Air Pollution in Developing Megacities: Beijing, Delhi


Air Quality & Human Health; Sources of air pollutants: Traffic emissions; Air Pollution in Developing Megacities: Beijing, Delhi