The influence of biogeochemistry and microbiology on Antarctic ice shelves
This PhD project will investigate how microbial communities effect the rate of ice shelf surface melt.
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. On some ice surfaces, this ‘bioalbedo’ influence is sufficient to significantly increase melt.
This project will explore whether this phenomenon occurs on Antarctic ice shelves, and how microbial activity can change the occurrence and biogeochemical characteristics of ice shelf surface melt.
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.
- Explore the activity of the community in the Cardiff Cold Climate lab, and assess how activity influences pigmentation.
- Use imaging techniques at NHM and Cardiff to understand how interactions between microbes and minerals support this diverse yet extreme ecosystem.
- Analyse, at the University of Bristol, meltwater samples collected with partners at GNS New Zealand and evaluate how the microbial activity in the debris changes the biogeochemistry of meltwater, and how this runoff can influence the surrounding oceans.
The student may have the opportunity to participate in Antarctic fieldwork, subject to logistical 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.
The student will receive exemplary laboratory training at three world-class institutions: Cardiff, Bristol and NHM.
At Cardiff they will conduct low temperature experiments to assess microbial activity and physical properties. At Bristol they will learn analytical techniques for assessing the biogeochemistry of extremely low concentration samples. At NHM they will receive training on up to date molecular analyses and imaging.
The student will also have the opportunity to visit the collaborating partners in New Zealand to learn about the wider ice shelf processes, and potentially to participate in polar fieldwork.
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.
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.
Applications are primarily open to UK residents only (minimum residence of 3 years excluding time in further education), however, a limited number of full studentships are also available to EU residents. Students from EU countries who do not meet the residency requirements may still be eligible for a fees-only award but no stipend. Applicants who are classed as International for tuition fee purposes are not eligible for funding.
All applicants need to comply with the registered university's English-language requirements.
Applicants should have obtained or be about to obtain a First or Upper Second Class UK Honours degree, or equivalent qualifications gained outside the UK. Applicants with a Lower Second Class degree will be considered if they also have a master's degree.
How to apply
Applications should be made through the Cardiff University's online application system.
The deadline for applications is 8 January 2021.
Banwell et al. 2019 Direct measurements of ice-shelf flexure caused by surface meltwater ponding and drainage, Nature Communications 10: 730
Cook et al. 2019 Glacier algae accelerate melt rates on the western Greenland Ice Sheet, The Cryosphere Discussions
Glasser et al. 2006 Debris characteristics and ice-shelf dynamics in the ablation region of the McMurdo Ice Shelf, Antarctica, Journal of Glaciology, 52: 177
Hawes et al. 2018 The “Dirty Ice” of the McMurdo Ice Shelf: Analogues for biological oases during the Cryogenian, Geobiology 16: 369-377
Jungblut et al. 2017 Arctic Ice Shelf Ecosystems
Kingslake et al. 2017 Widespread movement of meltwater onto and across Antarctic ice shelves, Nature, 544: 349–352