African Humid Period floods on the Sahara Desert margins

To apply please use the online application form, simply search for PhD Geological Science and clearly state that you are applying for an ARIES PhD studentship and name the project SOGEES-1022-S1-P4 (ARIES, Stokes), at the top of your personal statement.

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Whilst you can apply for up to three ARIES projects, you must submit a separate application for each.

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Dr Martin Stokes

Professor Anne Mather

Professor Fin Stuart

Dr Sarah Boulton

Competition Funded PhD Project (Students Worldwide)


Project details

This project investigates the size, timing and impact of African Humid Period (AHP) floods on upland landscapes along the Sahara Desert margins. Wobbling of the Earth’s axial spin alters atmospheric circulation patterns every ~20,000yrs, repeatedly bringing wetter climates and flooding (~5,000yr duration) to continental Africa ('Greening’ of the Sahara). Investigations will analyse mountain fronts from different latitudinal and continentality contexts using Quaternary-Recent alluvial fans (cone-shaped sediment bodies formed on valley sides and mountain fronts). These landforms possess flood-related sedimentary and geomorphological records with significant but unrealised large spatial and long temporal potential to inform on climate change sensitive drylands; areas of early human occupation (archaeology) and modern population pressures (flood hazard).

The PhD research will investigate key sites along the western Saharan Desert margin (offshore islands [humid], coastal [arid] and inland [hyperarid]: Cape Verde-Morocco: 14-28°N). Flood size quantification will involve measurement of flood sediments (boulder size) and geomorphology (slope and flood inundation area). This uses fieldwork and satellite analysis of palaeoflood and modern (for comparison / calibration) flood sites using hydrological modelling approaches (e.g. flood regime). The timing of flood events uses cosmogenic exposure dating techniques (i.e. 3He, 10Be, 26Al) applied to boulder surfaces deposited from different flood events. The impact of localised alluvial fan AHP flooding will utilise inter-site comparisons and comparisons with hydrological change datasets from other AHP archives (rivers, lakes, marine cores).

The PhD student will become a flood scientist with a field-laboratory-computing skillset of relevance to environmental government agencies or industry consultancy employment. Specialist training in remote sensing, fieldwork, geochronology, and hydrological modelling will utilise Plymouth/Glasgow expertise and laboratories (SUERC). Generic research training skills will be undertaken via the ARIES/Plymouth doctoral training colleges (project management, health and safety, data management, research communication / publishing). The student will become a member of international flood science networks (INQUA) for conference results communication and advanced training workshop opportunities.

This PhD is suitable for candidates with degrees in Geology / Earth Science / Physical Geography. Fieldwork and GIS experience is desirable. A willingness to travel and rise to the challenge of working in hot / remote desert locations is important.


Funding notes

This project has been shortlisted for funding by the ARIES NERC DTP and will start on 1 October 2022.

Successful candidates who meet UKRI’s eligibility criteria will be awarded a NERC studentship for 3.5 years, covering fees, stipend (£15,609 p.a. for 2021-22) and research funding. International applicants (EU and non-EU) are eligible for fully-funded UKRI studentships.

ARIES students benefit from bespoke graduate training and £2,500 for external training, travel and conferences.

ARIES is committed to equality, diversity, widening participation and inclusion. Academic qualifications are considered alongside non-academic experience. Our recruitment process considers potential with the same weighting as past experience.

For information and full eligibility visit


DeMenocal, P.B., Tierny, J.E., 2012. Green Sahara: African Humid Periods Paced by Earth's Orbital Changes. Nature Education Knowledge 3, 12.

Larrasoaña, J.C., et al., 2013. Dynamics of green Sahara periods and their role in hominin evolution. PloS one, 8(10), p.e76514.

Skonieczny, C., et al., 2015. African humid periods triggered the reactivation of a large river system in Western Sahara. Nature Communications 6:8751 doi: 10.1038/ncomms9751

Stokes, M., et al., 2017. Controls on dryland mountain landscape development along the NW Saharan desert margin: Insights from Quaternary river terrace sequences (Dadès River, south-central High Atlas, Morocco).Quaternary Science Reviews, 166, pp.363-379.

Stokes, M., Gomes, A., 2020. Alluvial fans on volcanic islands: A morphometric perspective (São Vicente, Cape Verde). Geomorphology368, 107356.