How have major changes in marine atmospheric sulfur emissions influenced aerosol composition and acidity?

For any generic questions on ARIES, studentships and selection processes, prospective applicants should contact Professor Dave Bilton for projects in School of Biological and Marine Sciences and Professor Gregory Price for School of Geography, Earth and Environmental Sciences.

For specific details on individual projects, please contact the project's primary supervisor.


Dr Thomas Bell (Plymouth Marine Laboratory)

Dr Ming-Xi Yang (Plymouth Marine Laboratory)

Dr Simon Ussher (University of Plymouth)

To apply please use the online application form, simply search for PhD Environmental Sciences and clearly state that you are applying for an ARIES PhD studentship and name the project SOGEES-1022-S1-P1 (ARIES, Bell), at the top of your personal statement.

Online application

Whilst you can apply for up to three ARIES projects, you must submit a separate application for each.

Take a look at the Doctoral College information on applying for a research degree.


Dr Thomas Bell (Plymouth Marine Laboratory)

Dr Ming-Xi Yang (Plymouth Marine Laboratory)

Dr Simon Ussher (University of Plymouth)

Competition Funded PhD Project (Students Worldwide)

Project details

Scientific background: Sulfur plays a key role in the marine atmosphere, and has a major influence on atmospheric particles and climate. Sulfur emissions result from natural seawater processes and anthropogenic activities. The marine atmosphere is undergoing a period of profound change. A series of regulations aimed at improving air quality have reduced anthropogenic sulfur emissions, which impact the composition and acidity of atmospheric particles (aerosols). Aerosol acidity is fundamental in atmospheric chemistry and is relevant to air quality, ecosystems, and climate.

Terrestrial anthropogenic sulfur emissions have steadily declined since the 1980s. In contrast, a global mandate in 2020 led to an abrupt seven-fold drop in emissions from international shipping. Natural/anthropogenic contributions to the marine sulfur burden and impacts on aerosol acidity are poorly understood because there has been no post-2020 assessment of the global implications of sulfur emission changes.

Project aim:

Constrain natural and anthropogenic sulfur emissions, improve understanding of atmospheric sulfur cycling post-2020, and assess the impacts upon the marine atmosphere.

Research methodology: The student will analyse marine sulfur gas and aerosol samples, and measure natural/anthropogenic contributions using isotope ratios. Samples will be collected at the southwest UK (Penlee Point), the Azores (ACE-ENA), and Bermuda (Tudor Hill) field sites, then data compared and evaluated against the GEOS-Chem model to improve understanding of marine aerosol, acidity and the impacts on biogeochemical cycles.

Training opportunities:

The student will gain field experience (observatory site visits) and specialist analytical lab experience (PML Air-Sea Exchange group: novel method development to trap sulfur gases for fluorescence detection; and UoP: analysing aerosol samples with Ion Chromatography and Inductively Coupled Plasma Mass Spectrometry). They will visit the BGS Isotope facility, attend the NCAS summer school, gain data interpretation skills (Python), and learn valuable academic, industrial and consultancy career skills (e.g. transferable writing and presentation skills, good laboratory practice, quality assurance and safety procedures).


Person specification:

Suited for someone passionate about environmental research and field work, with an aptitude for operating scientific instrumentation and degree-level qualifications in Environmental, Chemical, Marine or Atmospheric Sciences. Those with other numerate degrees (e.g. Physics, Engineering) are also encouraged to apply.


Funding notes

This project has been shortlisted for funding by the ARIES NERC DTP and will start on 1 October 2022.

Successful candidates who meet UKRI’s eligibility criteria will be awarded a NERC studentship for 3.5 years, covering fees, stipend (£15,609 p.a. for 2021-22) and research funding. International applicants (EU and non-EU) are eligible for fully-funded UKRI studentships.

ARIES students benefit from bespoke graduate training and £2,500 for external training, travel and conferences.

ARIES is committed to equality, diversity, widening participation and inclusion. Academic qualifications are considered alongside non-academic experience. Our recruitment process considers potential with the same weighting as past experience.

For information and full eligibility visit