Dr Will Seviour, Department of Mathematics, College of Engineering, Mathematics and Physical Sciences, University of Exeter
Prof Geoff Vallis, Department of Mathematics, College of Engineering, Mathematics and Physical Sciences, University of Exeter
Dr Nick Teanby, School of Earth Sciences, University of Bristol
Dr Dann Mitchell, School of Geographical Sciences, University of Bristol
Location: University of Exeter, Streatham Campus, Exeter, EX4 4QJ
This project is one of a number that are in competition for funding from the NERC GW4+ Doctoral Training Partnership (GW4+ DTP). The GW4+ DTP consists of the GW4 Alliance of research-intensive universities: the University of Bath, University of Bristol, Cardiff University and the University of Exeter plus five unique and prestigious Research Organisation partners: British Antarctic Survey, British Geological Survey, Centre for Ecology & Hydrology, the Natural History Museum and Plymouth Marine Laboratory. The partnership aims to provide a broad training in the Earth, Environmental and Life sciences, designed to train tomorrow’s leaders in scientific research, business, technology and policy-making. For further details about the programme please see http://nercgw4plus.ac.uk/
For eligible successful applicants, the studentships comprises:
- A stipend for 3.5 years (currently £15,009 p.a. for 2019/20) in line with UK Research and Innovation rates
- Payment of university tuition fees;
- A research budget of £11,000 for an international conference, lab, field and research expenses;
- A training budget of £3,250 for specialist training courses and expenses.
- Travel and accommodation is covered for all compulsory DTP cohort events
- No course fees for courses run by the DTP
We are currently advertising projects for a total of 10 studentships at the University of Exeter.
Titan has the only dense, nitrogen-rich atmosphere in the Solar System, besides Earth’s. It is also the only other solar system body with stable liquid currently on its surface, in the form of methane rivers and lakes (Fig. 1). From these lakes, methane evaporates, forms clouds, and rain, analogous to the hydrological cycle on Earth. In Titan’s upper atmosphere, photochemical reactions produce complex organic molecules, the building blocks of life. Titan is therefore an ideal testing ground for our theories about planetary climate, habitability, and astrobiology. Indeed, NASA has recently selected the Dragonfly spacecraft mission to explore Titan’s atmosphere and surface (Fig. 2), to be constructed and launched within the next decade.
In addition to vital observational data, much can be learned by using numerical models to simulate Titan’s atmosphere and climate. This has the added benefit of testing the robustness of these models, which are usually applied to Earth’s atmosphere, and thereby improving our confidence in projections of future climate change. However, few such models have been developed for Titan, and those that exist have a very limited representation of its methane cycle, the transport of trace gases, and other important processes.
Project Aims and Methods
This project aims to adapt a numerical model of Earth’s atmosphere and apply it to Saturn’s exotic moon Titan. The main tool used will be the Isca climate modelling framework (https://execlim.github.io/IscaWebsite/index.html
), primarily developed within co-supervisor Prof Vallis’ group. Isca is a uniquely flexible model that can be used to understand planetary atmospheres at varying levels of complexity. The first aim of this project will be to adapt Isca to Titan’s atmosphere, so that it is capable of capturing the major features of Titan’s atmospheric circulation and climate. This will allow us to tackle several important scientific questions. There is a large amount of flexibility here, and we encourage the research direction to be driven by the interests of the student. Possible directions of research include:
Incorporating an idealized ‘hydrology’ and land surface flow model to understand the seasonality of Titan’s methane cycle, including the apparent seasonal drying of its lakes.
Comparison of Earth’s hydrological cycle under warm paleo- or future climate scenarios with Titan’s methane cycle.
Using a comprehensive radiative transfer model (SOCRATES), along with observational data, to understand trace gas abundances.
Understanding the connection between Titan’s atmospheric chemistry and dynamics, including its potentially unstable annular polar vortex, as also found on Mars.
References / Background reading list
1. Vallis, G. K., et al. (2018). Isca, v1.0: a framework for the global modelling of the atmospheres of Earth and other planets at varying levels of complexity, Geosci. Model Dev., 11, 843–859.
2. Seviour, W. J. M., D. W. Waugh, and R. K. Scott (2017). The Stability of Mars’ Annular Polar Vortex, J. Atmos. Sci., 74, 1533-1547.
3. Hörst, S. M. (2017), Titan's atmosphere and climate, J. Geophys. Res. Planets, 122, 432– 482.