How do microbiological processes influence ice shelves?

Antartic ice shelf

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.


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.


Apply for this project

Application deadline: 9 January 2023

Lead supervisor

Dr Elizabeth Bagshaw

Cardiff University

Museum supervisor

Dr Anne D. Jungblut

Other supervisors

Dr Sammie Buzzard

Cardiff University 

Dr Chris Williamson

University of Bristol

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

Funded by