Project Description

Primary Supervisor - Dr Andrew Orr

Scientific background

Mountains (or "orography") have a substantial effect on the atmospheric circulation. This includes atmospheric disturbances known as orographic gravity waves, generated by the winds flowing over orography. These waves propagate upwards and eventually become unstable and break down, which results in orographic gravity wave drag. This is a frictional force that decelerates upper-level winds and causes clear-air turbulence. However, a lack of understanding of these processes results in a poor representation of orographic gravity wave drag in numerical weather prediction (NWP) models, which subsequently leads to large errors in their representation of atmospheric circulation and thus weather forecasts. Due to the importance of this problem, a major international atmospheric research programme called TEAMx took place over the Alps in 2025 with the aim to improve weather forecasts in complex terrain, which included measurements from weather balloons and aircraft of orographic gravity waves.

Research methodology

The individual will use the measurements from the TEAMx campaign to improve our process-based knowledge of orographic gravity wave drag and its representation in NWP models. Specifically:

- Identify case studies periods with substantial orographic gravity wave activity.

- Use the observations to investigate how orographic gravity waves are generated for the case studies, and how they propagate upwards and eventually break down.

- Conduct multi-scale simulations of the case studies using Met Office NWP models and assess how realistically they capture orographic gravity waves and their effects.

- Optimise these models and improve their accuracy.

Training

The individual will receive training in mountain meteorological processes and fluid dynamics, running Met Office NWP models, and data analysis. They will have the opportunity to work alongside other scientists at the British Antarctic Survey and the University of Bath working on another TEAMx project on orographic gravity waves, including opportunities to attend project meetings, as well as international TEAMx meetings. They will also receive cohort residential training, and dedicated funding for conferences and skills development.

Person specification

The individual should have a degree in Meteorology, Physics, Maths or a similar quantitative science. An interest in meteorology, data analysis and numerical modelling is essential.

Entry Requirements

At least UK equivalence Bachelors (Honours) 2:1. English Language requirement (Faculty of Science equivalent: IELTS 6.5 overall, 6 in each category).

Funding

ARIES studentships are subject to UKRI terms and conditions(opens in a new window). Successful candidates who meet UKRI’s eligibility criteria will be awarded a fully-funded studentship, which covers fees, maintenance stipend (£21,805 p.a. for 2026/27) and a research training and support grant (RTSG). A limited number of studentships are available for international applicants, with the difference between 'home' and 'international' fees being waived by the registering university. Please note, however, that ARIES funding does not cover additional costs associated with relocation to, and living in, the UK, such as visa costs or the health surcharge.

ARIES is committed to equality, diversity, widening participation and inclusion(opens in a new window) in all areas of its operation. We encourage applications from all sections of the community regardless of gender, ethnicity, disability, age, sexual orientation and transgender status. Projects have been developed with consideration of a safe, inclusive and appropriate research and fieldwork environment. Academic qualifications are considered alongside non-academic experience, with equal weighting given to experience and potential.

After submitting their application for the relevant ARIES project(s), applicants are expected to complete the ARIES Equality and Diversity Form Applicants - 2027 Entry – Fill in form(opens in a new window).One form is required per application, so applicants applying to more than one project must complete a separate form for each.

Please visit www.aries-dtp.ac.uk(opens in a new window) for further information.

References

Sandu, I., van Niekerk, A., Shepherd, T.G., et al. (2019), Impacts of orography on large-scale atmospheric circulation, npj Clim Atmos Sci 2, 10, https://doi.org/10.1038/s41612-019-0065-9.

Hindley, N. P., Wright, C. J., Gadian, A. M., Hoffmann, L., Hughes, J. K., Jackson, D. R., King, J. C., Mitchell, N. J., Moffat-Griffin, T., Moss, A. C., Vosper, S. B., and Ross, A. N. (2021), Stratospheric gravity waves over the mountainous island of South Georgia: testing a high-resolution dynamical model with 3-D satellite observations and radiosondes, Atmos. Chem. Phys., 21, 7695–7722, https://doi.org/10.5194/acp-21-7695-2021

Orr, A., J. S. Hosking, L. Hoffmann, J. Keeble, S. M. Dean, H. K. Roscoe, L. Abraham, S. Vosper, and T. Phillips (2015), Inclusion of mountain wave-induced cooling for the formation of PSCs over the Antarctic Peninsula in a chemistry-climate model, Atmos. Chem. Phys., 15, 1071-1086, https://doi.org/10.5194/acp-15-1071-2015

Vosper, S. B., Ross, A. N., Renfrew, I. A., Sheridan, P., Elvidge, A. D., and Grubišić, V. (2018), Current challenges in orographic flow dynamics: turbulent exchange due to low-level gravity-wave processes, Atmosphere, 9, 361, https://doi.org/10.3390/atmos9090361

Smith, R. B., Skubis, S., Doyle, J. D., Broad, A. S., Kiemle, C., and Volkert, H. (2002), Mountain waves over Mont Blanc: Influence of a stagnant boundary layer, J. Atmos. Sci., 59, 2073–2092, https://doi.org/10.1175/1520-0469(2002)059<2073:MWOMBI>2.0.CO;2

Winds and Waves in the Alpine Mountains (ORR_BAS_ARIES27)

Welcome to Norwich

Project Description

Entry Requirements

Funding

References