Imperial College London Featured PhD Programmes
Xi’an Jiaotong-Liverpool University Featured PhD Programmes
Life Science Zurich Graduate School Featured PhD Programmes

Assessing the Impact of Dynamic Turbulence Modelling on Sub-Kilometric Unified Model Simulations of Convective Storms during WesCon, NERC GW4+ DTP PhD studentship for 2022 Entry, PhD in Mathematics

   College of Engineering, Mathematics and Physical Sciences

  Dr Georgios Efstathiou, , , Dr Adrian Lock  Monday, January 10, 2022  Competition Funded PhD Project (Students Worldwide)

Exeter United Kingdom Applied Mathematics Climate Science Data Analysis Geophysics Mathematics

About the Project

Project Background

Convective storms are responsible for many of the most violent meteorological phenomena on Earth. Deep convection is usually highly localised and difficult to accurately predict as it is dependent on interactions across a wide range of scales, from small-scale turbulent motions up to the synoptic-scale environment. A substantial step forward in our ability to forecast convective events has come with the advent of high-resolution Numerical Weather Prediction (NWP) models. However, the improvements from enhancing the model resolution are not always apparent as model results can be very sensitive to the treatment of the unresolved turbulence length scales [1]. We encounter such modelling challenges because the high-resolution NWP grid spacings correspond to the dominant scales of boundary layer turbulence and cloud development, and to scales characterising cloud mixing with its immediate environment. 

Project Aims and Methods

This PhD project aims at improving the representation of convective storms in sub-km NWP by implementing and assessing a dynamic, scale-adaptive turbulence model in the operational Met Office Unified Model (UM). The dynamic turbulence modelling approach has been developed from the Computational Fluid Dynamics community to alleviate the need for an a priori specification of closure parameters in turbulence models. This approach can provide dynamically derived length scales that will adapt to the partially resolved flow field in time and space. The use of dynamic length scales relaxes the strict assumption for a clear scale separation made in conventional turbulence schemes [2]. This can enable NWP models to better resolve convection across a range of sub-kilometric resolutions. 

The PhD student will have the opportunity to examine the performance and behaviour of the dynamic approach in a real-world setting by using data from the Wessex UK 2023 summertime convection measurement campaign (WesCon) to: a) validate individual components of the dynamic procedure and especially the spatial and temporal distribution of turbulence intensity in clouds and the boundary layer, b) improve our understanding of the relationships between boundary layer and convective clouds length-scales and c) explore the ability of the dynamic model to better represent the cloud structure and storm morphology while assessing its impact on forecast rainfall amount and intensity. The PhD project has the potential to shape the development of the Met Office’s next generation modelling system by utilising an intensive measurement campaign to develop, extend and test a new approach in realistic NWP applications.

Candidate requirements

Strong mathematical or physical sciences background is essential. Some coding experience is desirable.

Project partners

This project is co-sponsored by a Met Office CASE studentship. The PhD student will have the opportunity to take a 3-month placement at the Met Office and work closely with staff members.


The DTP offers funding to undertake specialist training relating to the student’s specialist area of research. The Met Office will provide training on the UM and its new modelling system.

Useful links

For information relating to the research project please contact the lead Supervisor via


NERC GW4+ DTP studentships are open to UK and Irish nationals who, if successful in their applications, will receive a full studentship including payment of university tuition fees at the home fees rate.

A limited number of full studentships are also available to international students which are defined as EU (excluding Irish nationals), EEA, Swiss and all other non-UK nationals. For further details please see the NERC GW4+ website.

Those not meeting the nationality and residency requirements to be treated as a ‘home’ student may apply for a limited number of full studentships for international students. Although international students are usually charged a higher tuition fee rate than ‘home’ students, those international students offered a NERC GW4+ Doctoral Training Partnership full studentship starting in 2022 will only be charged the ‘home’ tuition fee rate (which will be covered by the studentship). 

International applicants need to be aware that you will have to cover the cost of your student visa, healthcare surcharge and other costs of moving to the UK to do a PhD. More information on this is available from the universities you are applying to (contact details are provided in the project description that you are interested in.

The conditions for eligibility of home fees status are complex and you will need to seek advice if you have moved to or from the UK (or Republic of Ireland) within the past 3 years or have applied for settled status under the EU Settlement Scheme.

How to apply

In order to formally apply for the PhD Project you will need to go to the following web page.

The closing date for applications is 1600 hours GMT on Friday 10th January 2022.

Interviews will be held between 28th February and 4th March 2022.

If you have any general enquiries about the application process please email or phone: 0300 555 60 60 (UK callers) or +44 (0) 1392 723044 (EU/International callers). Project-specific queries should be directed to the main supervisor

Funding Notes

NERC GW4+ funded studentship available for September 2022 entry. For eligible students, the studentship will provide funding of fees and a stipend which is currently £15,609 per annum for 2021-22.


[1] Honnert, R., Efstathiou, G., Beare, R., Ito, J., Lock, A., Neggers, R., et al. (2020). The atmospheric boundary layer and the “gray zone” of turbulence: A critical review. .Journal of Geophysical Research: Atmospheres, 125.
[2] Efstathiou, GA, Plant, RS. (2019) A dynamic extension of the pragmatic blending scheme for scale-dependent sub-grid mixing. Quarterly Journal of the Royal Meteorological Society. 145: 884– 892.

Email Now