I am a geomorphologist using a combination of remote sensing, fieldwork, geospatial analysis and numerical modeling to investigate earth surface dynamics and hazards, predominantly in mountainous regions.

My passion for geomorphology really started during a BSc and MSc in Geography at Durham University, where I studied glacial landsystems and paraglacial dynamics in Iceland with Dave Evans. In 2009 I moved to Switzerland to do my PhD with Peter Molnar at ETH Zurich. My PhD research focused on landslide and debris flow processes in a Swiss alpine catchment and culminated in a new model, SedCas, now being applied in other catchments to model sediment cascades and debris flow hazard. Following my PhD, I moved to the USA where I worked with Josh Roering at the University of Oregon on longer term landscape evolution in northern California and particularly the role of slow moving landslides. In a second postdoc at the US Forest Service and Colorado State University (2015 – 2016), I investigated the response of catchments in the Colorado Front Range to an extreme flood event and learned a lot about fluvial geomorphology whilst roaming around the Rockies with Sandra Ryan and Sara Rathburn.

In my current position as Lecturer in Physical Geography and Natural Hazards at UEA, I am enjoying taking my research in new directions, benefiting from the rich, interdisciplinary nature of the School of Environmental Sciences. I am PI on two recently funded projects, BOULDER, investigating boulder hazard cascades in Nepal and SCaRP, investigating cascading landslide hazards in the Philippines. You can read more about these projects and our growing geomorphology group at UEA at my external group website: Geomorphology @ UEA  

Accounting for BOUlders in Landslide-flood Disaster Evaluation and Resilience (BOULDER), NERC SHEAR catalyst project, £250K

I am PI on this project investigating boulder hazard cascades in the Upper Bhote Koshi catchment in Nepal. Our team will map boulders, analyse controls on boulder production and hazard and track boulders in river channels using innovative sensors. We will work in close partnership with UK and Nepal based geohazard consultants, government agencies and NGOs to deliver research that will increase resilience to landslide and flood disasters. 

Landslide control on river channel form and process

In previous research I found empirical evidence of a negative feedback of landslide- delivered boulders on channel incision, knickpoint retreat and ongoing landscape erosion rates and evolution in northern California. Such a feedback has since been corroborated theoretically through numerical modeling that demonstrates how blocks both armour the river bed from incision and increase form drag, thus reducing stream power available to act on the channel bed and move boulders. This has implications for extracting tectonic information from river profiles and preconditioning the response to rivers to shorter-term flood events. I continue to research the influence of landslides on channel form and process in this and other regions. 

Wood-sediment interaction in mountain rivers

I became interested in the role of wood and its modulation of fluvial sediment transport and geomorphology whilst a postdoc at the US Forest Service and Colorado State University. My main project was investigating the geomorphic impact of an extreme flood in the Colorado Front Range in 2013 but on the side I set up a project with Sandra Ryan of the USFS on the response of fluvial bedload transport to increased wood loading. In August 2016, we radio-tagged 1000 cobbles and multiple pieces of wood within St Louis Creek in the US Forest Service Fraser Experimental Forest. We found and resurveyed the positions of 90% of these in August 2017. We will continue to monitor the movement and interaction of cobbles and large wood over the next years in response to changes in wood loading and discharge. Miles Clark is a PhD student working on this project. 

Landslide and landscape response to increased climate variability, northern California

I am interested in how landslides respond to cycles of drought and rainfall, particularly in clay dominated lithologies, susceptible to wetting and drying. I recently demonstrated the dramatic slow-down of earthflows in northern California in response to extreme drought. I continue to monitor earthflows in the region using satellite imagery available through Planet Labs and in collaboration with Alexander Handwerger and Josh Roering. I also have an undergraduate student investigating the sediment discharge response to cycles of drought and extreme rainfall in the region. 

Modeling lahar hazard on Montserrat

Lahars are hazardous sediment transport agents that gradually remove volcanic sediment deposited on the flanks of volcanoes during eruptions. I am interested the how exhaustion of this sediment supply by lahars influences subsequent lahar magnitude and frequency. I supervise a PhD student, James Christie, who is applying my sediment cascade model, SedCas, to model this process on the Caribbean island of Montserrat. This project is in collaboration with Melanie Froude (University of Sheffield) and Jenni Barclay (UEA).

Landscape preconditioning of landsliding in Nepal

A number of factors precondition hillslopes to fail, sometimes with no apparent trigger. These are climatic and tectonic processes that gradually weather and weaken the bedrock and increase the supply of mobilizable regolith such as earthquakes and rainfall events. Of course many of these processes may also be triggering factors, but there is always a long history of damage incurred to a slope in the lead up to slope failure. I co-supervise a PhD student working on untangling the varied controls that precondition and trigger landslides in Nepal (road building, river incision, earthquakes). This project is in collaboration with Sarah Boulton and Martin Stokes (University of Plymouth) and Michael Whitworth (Aecom).

Soft coastal cliff erosion

The east coast of the UK is one of the most vulnerable coastlines to erosion in the UK due to the high retreat rate of its soft cliffs.  Much research has focussed on the role of wave energy, modulated by tides, as a key driver of coastal erosion. Comparatively little attention has been given to role of subaerial processes in coastal erosion, although these may play an important role in driving cliff retreat, both through triggering and preconditioning slope failure (i.e. through weakening cliffs and making them more susceptible to wave erosion). Future climate projections for the UK suggest the increasing probability of warmer, drier summers and wetter winters. I hypothesize that the increased climate variability is likely to have significant impact on the cliff weathering and erosion especially where clay content is high. I currently have a PhD student working on this project in collaboration with Chris Hackney and Dan Parsons at the University of Hull, funded through Dan Parson’s ERC starter grant. I also have an undergraduate student looking at the role of subaerial processes in the evolution of cliffs along the coast that are no longer exposed to wave erosion. 

Modeling alpine catchment sediment cascades

Mountain basins are particularly sensitive to climate change due to the prevalence of ice and snow susceptible to melting and the rapid rainfall-runoff response of steep slopes. An increase in mass movements from rockfalls to debris flows is observed across the alps as a result of permafrost melt, glacier retreat and increased rainfall. SedCas is a model of an alpine catchment sediment cascade I developed in my PhD that shows the control of sediment supply at the head of the cascade (by landslides and rockfall for example) on debris flow hazard. Unpublished results suggest that sediment supply may limit the expected increase in debris flow hazard by the end of the century. However, the influence of climate change on sediment production needs further research. I co-supervise Jacob Hirschberg, a PhD student working on this topic based at WSL and ETH Zurich with Brian McArdell and Peter Molnar. 

I teach on ENV-6001B Geophysical hazards, ENV-5004B Applied Geophysics, ENV-5034A Geomorphology and ENV-7018A Research Topics in Earth Science.

I am the EnvSoc staff liaison and sit on the Staff Student Liaiason Committee and the Teaching Committee

I supervise two PhD students as primary supervisor and 3 more as co supervisor:

James Christie (UEA) (Primary supervisor) Modelling decadal-scale lahar hazard and landscape disturbance following volcanic eruption on the island of Montserrat, NERC EnvEast DTP

Miles Clark (UEA) (primary supervisor) Rock and Roll: Passive and automated sensing of bedload and wood transport and interaction, NERC NEXUSS CDT

Joshua Jones (University of Plymouth) (co supervisor) Landslides in Nepal - exploring the role of earthquake preconditioning, NERC EnvEast DTP

Serena Teasdale (University of Hull) (co supervisor) Sticky cliffs - the role of clay in modulating the erosion of coastal cliffs, funded through Dan Parson's ERC starter grant

Jacob Hirschberg (WSL/ETH Zurich) (co supervisor) Climate change impact on mass movements, funded through Swiss Federal Institute for Forest, Snow and Landscape Research WSL internal funding