Profile
Marie Skłodowska–Curie Actions Fellow (MSCA) and Ph.D. candidate in Atmospheric Sciences at The Cyprus Institute. My research investigates how anthropogenic ammonia (NH₃) emissions influence upper-tropospheric aerosol formation and climate. I use the EMAC Earth system model, integrating mechanisms from the CLOUD experiment at CERN. I have completed secondments at the Max Planck Institute for Chemistry and CERN (CLOUD experiment), published in high-impact journals including PNAS and Nature, and served as a reviewer for Environmental Science & Technology.
Education
The Cyprus Institute
Research Project: Anthropogenic NH₃ in the Upper Troposphere: Global Impact on Particle Formation and Its Role in the Asian Tropopause Aerosol Layer
University College London
Degree Classification: Distinction
Research Project: Simulating the performances of ARIEL and JWST in probing the atmospheres of planets in the radius gap
Imperial College London
Degree Classification: Distinction
Research Project: Inertial stability and the behaviour of tropical cyclones
Imperial College London
Degree Classification: Upper Second Class Honours
Research Project: Sonoluminescence – Generating light from acoustically-driven bubbles
The English School, Nicosia, Cyprus
A Levels: Physics (A*), Mathematics (A*), Further Mathematics (A*), Biology (A), Modern Greek (A)
Research Achievements & Peer Recognition
Summary of Research
I quantify the global impact of anthropogenic NH₃ on new particle formation (NPF) in the upper troposphere, where aerosols shape cloud properties and climate. Using Earth system modelling and CLOUD-derived NPF mechanisms, I show that NH₃—transported by convection from agricultural sources—enhances aerosol formation through interactions with sulfuric and nitric acids.
Simulations reveal that anthropogenic NH₃ increases cloud-forming particle concentrations by up to 2.5× over high-emission regions and raises aerosol optical depth by as much as 80%, amplifying climate effects. This work advances NH₃-driven NPF representation in global models, improving climate projections and informing policy.
Awards & Recognition
- Media recognition of PNAS publication: Featured and promoted through official PNAS channels with broad engagement across platforms such as Twitter, LinkedIn and Bluesky (2025).
- Marie Skłodowska–Curie Actions (MSCA) CLOUD-DOC Fellowship (EU-2023).
- Ogden Prize: Awarded annually to one student for outstanding achievement in the Communicating Physics course (Imperial College London, 2019).
- As a result of the Ogden Prize, my name was written into the memory of the magnetometer instrument of the Solar Orbiter spacecraft (Imperial College London, 2019).
Publications
- Xenofontos, C., et al. “Global impact of anthropogenic NH₃ emissions on upper tropospheric aerosol formation.” Proceedings of the National Academy of Sciences 122.44 (2025): e2506658122.
- Xenofontos, C., et al. “The impact of ammonia on particle formation in the Asian Tropopause Aerosol Layer.” npj Climate and Atmospheric Science 7.1 (2024): 215.
- Russell, D. M., Xenofontos, C., et al. “Isoprene chemistry under upper-tropospheric conditions.” Nature Communications 16.1 (2025): 8555.
- Bhattacharyya, N., Xenofontos, C., et al. “Isoprene aerosol growth in the upper troposphere: application of the Diagonal Volatility Basis Set to cloud chamber measurements.” ACS ES&T Air 2.10 (2025): 2092–2104.
- Shen, J., Xenofontos, C., et al. “New particle formation from isoprene under upper-tropospheric conditions.” Nature 636.8041 (2024): 115–123.
Research Experience & Service
Secondments
-
CERN CLOUD experiment, Geneva, Switzerland (2023–2026)
Supported experimental campaigns through night shifts and contributed to planning discussions. -
Airmodus Ltd., Helsinki, Finland (2024)
Three-week secondment to enhance the Airmodus PSM inversion tool in Python, improving user interface legibility, adding error metrics and refining data visualization. -
Max Planck Institute for Chemistry, Mainz, Germany (2023)
Two-month collaboration developing the EMAC model setup for simulating atmospheric particle formation and evaluating its climate impact.
Conferences
- COMECAP, Nicosia, Cyprus (2025) – Oral: Impact of anthropogenic NH₃ on UT aerosol.
- ICNAA, Vienna, Austria (2025) – Oral: Impact of anthropogenic NH₃ on UT aerosol. Served as Session Chair.
- EGU General Assembly, Vienna, Austria (2025) – Oral: Anthropogenic NH₃ impact on UT aerosol composition and climate forcing.
- EAC, Tampere, Finland (2024) – Oral: Impact of NH₃ on particle formation in the Asian Tropopause Aerosol Layer.
- EGU General Assembly, Vienna, Austria (2024) – Poster: Modelling the impact of NH₃ emissions on NPF in the Asian Monsoon UT.
Positions of Responsibility
The Cyprus Institute
- Represented student interests at the Graduate School level in academic and institutional decision-making.
- Organized student-led events, fostering academic engagement and community-building.
- Supported student well-being and productivity through peer outreach and feedback mechanisms.
- Acted as liaison between students and faculty, ensuring transparent communication and leadership representation.
CLOUD Collaboration
- Reviewed and provided feedback on student paper drafts to uphold scientific clarity.
- Ensured accuracy of author lists, affiliations and acknowledgements across CLOUD publications.
- Represented doctoral students in discussions with senior researchers on publication planning and policy.
Skills
Languages
- Greek (native)
- English (native)
- French (IGCSE)
Programming & Modelling
- Python
- Fortran
- Earth system model development (EMAC)
- HPC environments
- Unix/Linux
Software & Tools
- Microsoft Office (Word, Excel, PowerPoint)
- Git
- LaTeX
Certifications & Teaching
- Python Programming – Coursera & Python Institute Certified.
- Guided final-year physics students to win gold and silver medals in Physics Olympiads (Chelsea Academy, London).
- Experience with large-scale simulations, data analysis and collaborative research workflows.
Research Profiles & Contact