Dr Denis Sergeev

Biography

Dr Denis Sergeev is a Lecturer in the Astrophysics group at the University of Bristol. In his research, Denis uses numerical models of planetary climate to understand the complexity of various atmospheric processes involving dynamics, convection, clouds and lightning. Denis is also interested in the habitability of terrestrial exoplanets. Denis works closely with the Met Office, adapting their new atmospheric model, LFRic, for extraterrestrial environments.

Before joining the University of Bristol, Denis was a postdoctoral researcher at the Department of Physics and Astronomy, University of Exeter, where he worked with Nathan Mayne and Hugo Lambert on simulating the atmospheres of terrestrial exoplanets. Denis obtained a PhD in Meteorology from the University of East Anglia, under the supervision of Ian Renfrew and Thomas Spengler. Denis's PhD research focused on the climatology and dynamics of high-latitude mesoscale cyclones, known as polar lows. Prior to his PhD, Denis obtained a Specialist Diploma in Meteorology and Climatology from the Moscow State University.

Research interests

Over my career in exoplanet science, Denis has developed a keen interest in the following areas:

• Planetary atmospheres and habitability. Denis is interested in the potential for habitability of Earth-like exoplanets, which is shaped by non-linear climate feedback loops involving atmospheric dynamics and chemistry.
• Atmospheric aerosols. Aerosols - such as cloud condensates, photochemical hazes and mineral dust - play a crucial role in shaping planetary climates. Denis simulates their formation and evolution in planetary atmospheres using a hierarchy of numerical models, informed by latest telescope observations.
• Atmospheric convection. Convection is a major driver of energy transport in planetary atmospheres, and it is a key process in the formation of clouds and precipitation. Denis uses high-resolution models to resolve convective dynamics on a variety of exoplanets, including Earth-like planets and sub-Neptunes.
• Extraterrestrial lightning. Cloudy atmospheres produce electric discharges, including lightning. Lightning discharges break down gas molecules and thereby affect the atmospheric make-up. Denis incorporates lightning into his models of planetary atmospheres to understand its impact on the atmospheric chemistry and potential biosignatures.
• High-performance computing and model intercomparisons. 3D climate models are complex pieces of software that require significant computational resources. Denis uses supercomputers at the University of Bristol and the Met Office to simulate planetary climates. He also collaborates with researchers across the world to systematically compare different models, with the ultimate goal to build more robust and reproducible modelling frameworks. Denis is a co-chair of the international model intercomparison framework called CUISINES, supported by NASA.

Current researchers and PhD students