Micro-AUVs for biogeochemical measurements

Main Supervisor, Dr Adrian Nightingale, Engineering, University of Southampton; Dr Amber Annett, Ocean & Earth Science, University of Southampton; Dr Rand Ismael, Ocean Technology and Engineering, National Oceanography Centre; Professor Blair Thornton, Engineering, University of Southampton

Autonomous underwater vehicles (AUVs) are becoming increasingly widespread in ocean science as sensor platforms to obtain data with minimal human input and maximum efficiency (and hence reduce carbon footprint). They also offer capability to explore environments that are inaccessible to humans for practical or safety reasons (e.g. around and under sea ice and marine-terminating glaciers).  


While larger AUVs can be deployed with a large sensor payload, they are expensive to maintain and operate. Conversely micro-AUVs (e.g. ecoSub, Seaber) are operable by a single person. Their small size means they are much cheaper and can be deployed in much larger numbers - increasing the opportunities for use.


While there are a wide range of AUV sensors for physical parameters, the options are more limited for biogeochemical data. This problem is especially acute for micro-AUVs where small size creates strict requirements on size and power consumption and limits options. This project looks to exploit new technologies for micro-AUVs that enable biogeochemical measurements, and explore the scientific niches that micro-AUVs can be used for – for example the relative low cost of micro-AUVs makes them excellent candidates for work at marine terminating glaciers where ice fall is a risk



This project will exploit two key technologies: a water sampler for micro-AUVs developed last year in Southampton which is the first (to our knowledge) sampler for micro-AUVs. We have just been awarded a SMMI HEIF knowledge exchange funding to work with ecoSub for first field trials in 2024. Secondly, low power optical sensors from RI’s group. These are well suited to microAUVs because of their small size and low power draw. Current capabilities allow measurement of trace concentrations of methane and we expect additional parameters to come online during the PhD, including carbon dioxide and nitrous oxide.


The student will undertake:

  • Lab/tank testing of technology to characterise sampler/sensor operation and performance. Rigorously assess field worthiness and potential improvements. 
  • Make improvements as required (throughout the PhD) 
  • Explore different sampler designs (different sample sizes, requirements for a suite of parameters from nutrients to pollutants, accommodation of complementary sensors e.g. CT) 
  • Produce spare samplers for field deployment. 
  • Local deployments to trial and validate the technology (e.g. from Callista in Southampton Water, accompanying the Marine Autonomy group to Studland Bay).
  • Target a final polar deployment looking to sample/measure at marine terminating glaciers.


University of Southampton, Highfield Campus & National Oceanography Centre

All doctoral candidates will enrol in the Graduate School of NOCS (GSNOCS), where they will receive specialist training in oral and written presentation skills, have the opportunity to participate in teaching activities, and have access to a full range of research and generic training opportunities. GSNOCS attracts students from all over the world and from all science and engineering backgrounds. There are currently around 200 full- and part-time PhD students enrolled (~60% UK and 40% EU & overseas).  Specific training will include:


At Highfield the student will be trained on 3D printing and other simple fabrication skills to fabricate copies of the sampler. They will be trained on the operation of optical sensors. Learn basic operation of the ecoSub.  

At the Waterfront Campus (NOCS) the student will be trained in oceanographic sampling protocols for a range of biogeochemical parameters, to enable design for concentration-prone elements and facilitate field calibrations. 


Eligibility & Funding Details: 

Fully funded project - Application deadline date: 01-March-2024


Background Reading: 

Whitt, C., Pearlman, J., Polagye, B., et al. (2020). Future vision for autonomous ocean observations. Frontiers in Marine Science, 7, 697.

Birch, J. (2018). Collecting and processing samples in remote and dangerous places: the Environmental Sample Processor as a case study. Pure Appl. Chem. 90, 1625–1630. doi: 10.1515/pac-2018-0201

Krisch, S., Hopwood, M.J., Schaffer, J. et al. The 79°N Glacier cavity modulates subglacial iron export to the NE Greenland Shelf. Nat Commun 12, 3030 (2021).