
McMurdo ice shelf and Mount Discovery, Antarctica, image by Anne Jungblut
How can microbial activity change the occurrence and biogeochemical characteristics of ice shelf surface melt, and how does this impact ice shelf stability?
Project background
Predicting the future behaviour of ice shelves is critical for understanding how Antarctica will respond to climate warming. The presence of debris on ice shelf surfaces is known to change the albedo and enhance melt, but the debris itself has been the subject of minimal investigation.
The debris hosts microbial communities, including cyanobacteria with pigments that can darken surfaces sufficiently to increase local ablation rates (Jungblut et al. 2017). On some ice surfaces, this ‘bioalbedo’ influence is sufficient to significantly increase melt.
This project will explore whether this phenomenon occurs on Antarctic iceshelves, and how microbial activity can change the occurrence and biogeochemical characteristics of ice shelf surface melt, and how this may impact ice shelf stability.
Project aims and methods
The project will characterise the microbial communities that inhabit debris on the surface of the Ross Ice Shelf, and investigate their impact on the surrounding environment.
The student will use state of the art microbial techniques to analyse the community composition in labs at the Natural History Museum. The student will:
- explore the activity of the community in the Cardiff Cold Climate lab, and assess how activity influences pigmentation
- assess the algal behaviour and productivity at Cardiff and the Bristol MicroLab
- use imaging techniques at NHM and Cardiff to understand how interactions between microbes and minerals support this diverse yet extreme ecosystem
- use the data collected to drive a numerical model of ice shelf processes, incorporating the impacts of sediment and biological activity into a hydrological model
The student may have the opportunity to participate in polar fieldwork, subject tologistical and funding constraints, and here they will conduct in situ experiments to understand the variability of the microbial activity across the shelf.
The data collected will be synthesised to build a comprehensive picture of this little-explored ecosystem, to help understand how microbial functions influence wider environmental processes.
Candidate requirements
This cross-disciplinary project requires diverse skills in biogeochemistry, microbiology and earth science; few candidates will have all the skills required at the beginning of the project, so the key requirement is enthusiasm and willingness to learn.
Training
The student will receive exemplary laboratory training at two world-class institutions: Cardiff and NHM. At Cardiff they will conduct low temperature experiments to assess microbial activity and physical properties. At NHM they will receive training on up to date molecular analyses and imaging. Throughout the project the student will have the support of a supervisory team to develop their scientific skills, and access to a range of training opportunities across the GW4 and NERC.
How to apply
Details about how to apply for this project can be found here. We suggest you also read our helpful document about applying for a PhD.
Find out more about the GW4 Doctorial Training programme.
Further reading
Banwell et al. (2019) Direct measurements of ice-shelf flexure caused by surface meltwater ponding anddrainage, Nature Communications
Bell et al. (2017) Antarctic ice shelf potentially stabilized by export of meltwater in surface river, Nature 544, 344–348
Bell et al. (2018) Constraining Recent Ice Flow History at Korff Ice Rise, West Antarctica, Using Radar and Seismic Measurements of Ice Fabric JGR Earth surface
Buzzard, S., Feltham, D. and Flocco, D. (2018) Modelling the fate of surface melt on the Larsen C Ice Shelf. Cryosphere 12(11), pp. 3565-3575
Glasser et al. (2006) Debris characteristics and ice-shelf dynamics in the ablation region of the McMurdo Ice Shelf, Antarctica, Journal of Glaciology
Hawes et al. (2018) The “Dirty Ice” of the McMurdo Ice Shelf: Analogues for biological oases during the Cryogenian, Geobiology
Jungblut et al. (2017) Arctic Ice Shelf Ecosystems
Kingslake et al. (2017) Widespread movement of meltwater onto and across Antarctic ice shelves, Nature
Williamson et al. (2020) Algal photophysiology drives darkening and melt of the Greenland Ice Sheet, Proceedings of the National Academy of Sciences, 117 (11) 5694-5705
Museum supervisor
Other supervisors
Cardiff University
University of Bristol

Joint PhD training partnerships between the Natural History Museum and the Great Western Four, Bath, Bristol, Cardiff and Exeter universities.