PhD PROJECT ADVERTISED: Sediment mobility in Himalayan rivers recorded by seismic monitoring with implications for flood risk under a changing climate

Supervisors: Prof Hugh Sinclair, Dr Mark Naylor, Dr Mikael Attal

Summary

Big Himalayan rivers cause major floods when their channels switch course. This project will use seismic monitoring to determine the thresholds for this process and consider implications for flood risk.

Project background

The large rivers draining the Himalaya are prone to abrupt switching of their channel courses as they exit the mountain front and enter the Gangetic Plains. This has major implications for flood early warning systems and future land-use planning. This project will work with colleagues in Nepal and India to install a network of seismic monitors next to the Karnali and Kosi rivers in order to monitor the onset of mobility of coarse bedload (mainly cobbles). This will build on expertise we have through ongoing research monitoring bedload movement in the Glen Feshie in the Cairngorms, and initial fieldwork will accompany researchers in this field site to understand the technique. The two field sites in the Himalaya will be installed at the start of the project with local community members employed to maintain and download data. The data will then be analysed using the time series of power spectra of seismic frequencies in order to characterise the signal from water flow, environmental noises and bedload movement. These data will then be compared to the river level data from the gauging stations in order to assess the threshold value of river level that initiates bedload motion, and hence increases the likelihood of channel switching. This information will then be shared with the two NGOs with whom we are partnering (Practical Action Nepal and ICIMOD), who will integrate the information into flood early warning systems and DRR strategies in the regions. Looking into the future, the information from this project will enable forecasts to be made of changing flood risk in response to climatic changes in the region.

For more information see: https://www.ed.ac.uk/geosciences/study/degrees/research-degrees/phd-projects/physical-sciences?item=1424