Drivers of the upper atmosphere (CENTA 2025-B31)

The thermosphere is a region of the Earth’s upper atmosphere, spanning altitudes between approximately 80 km and 500 km. It is one of the least understood regions of the terrestrial environment due to the challenges inherent in making observations at these high altitudes. Estimating the thermospheric density is the greatest challenge when predicting satellite orbits. Inaccurate predictions lead to unnecessary collision avoidance manoeuvres which uses fuel and reduces the operational lifetime of the satellite (Hapgood, 2021). The European Space Agency’s (ESA) Swarm mission is currently making in-situ observations the thermosphere. Swarm uses a multi-satellite approach and also observes the ionosphere, that is the part of the upper atmosphere which is comprised of plasma, at a range of scale sizes (Jin et al., 2022). This has enabled numerous studies of the multi-scale ionosphere, as reviewed by Wood et al. (2022). The University of Birmingham (UoB) have built models of the multi-scale ionosphere using observations from Swarm (Wood et al., 2024; ESA contract 4000130562/20/I-DT). The performance assessment of these models (Spogli et al., 2024) identified both strengths and limitations, and led to ESA awarding an additional 400,000 EUR for model development (ESA contract: 4000143413/23/I-EB). One of the model developments, led by the UoB, uses a new high-resolution thermospheric density data product of to drive the ionospheric model. This has led us to consider the inverse question: Could ionospheric measurements be used to infer the properties of the thermosphere? If so, what are the benefits? 

The purpose of this Ph.D. is to conduct a series of linked studies to determine: The statistical relationship between the thermospheric density and the ionospheric variability on different timescales and in different latitudinal regions. This will advance our understanding of the dynamics and morphology of the thermosphere. To what extent the thermospheric density can be forecasted from ionospheric observations, and the forecast horizon. This will advance our understanding of the fundamental timescales on which the thermosphere fluctuates. The improvement to predictions of satellite orbits using this approach. Project Highlights: Determining the drivers of the upper atmosphere, and how these vary by latitudinal region. Determining the characteristic timescales over which changes in the upper atmosphere occur. Improving models used to predict the orbits of satellites.

For further information on this project and details of how to apply to it please visit https://centa.ac.uk/studentship/2025-b31-drivers-of-the-upper-atmosphere/ Further information on how to apply for a CENTA studentship can be found on the CENTA website: https://centa.ac.uk/

Funding notes:

The CENTA DTP is currently awaiting confirmation of funding under the BBSRC-NERC Doctoral Landscape Award (DLA) scheme, which is the new name for Doctoral Training Partnerships (DTPs). This funding will support cohorts starting from 2025 onwards. We anticipate receiving further information by late October or early November 2024. Funding for this PhD opportunity is therefore subject to this confirmation. For further information please visit https://centa.ac.uk/. UKRI allows international students to be eligible for studentships but only for a maximum of 30% of the cohort. Please be aware that CENTA funding does not cover any additional costs relating to moving to and residing in the UK. All international applicants must ensure they can fulfil the University of Birmingham’s international student entry requirements, which includes English language requirements. For further information please visit https://www.birmingham.ac.uk/postgraduate/pgt/requirements-pgt/international/index.aspx.