A new approach to navigating uncertainty in climate-related hydrologic risk

This project develops the storyline approach, focusing on future drought risk in the United Kingdom. The proposed concept is to navigate the cascade of uncertainty to analyse and bound the system components contributing to hydrologic risk, and develop storylines that crystallize that risk. The storylines will be developed to characterize the full range of potential changes in climate that are relevant to drought occurrence (such as change in the frequency of successive dry winters, and delays to the start of the winter recharge season). These can then be used to stress-test resilience in robust, non-probabilistic frameworks such as Structured Decision Making, which is becoming widely used in hydrology (Brown et al. 2012 Water Resour. Res.). At the climate end, the storyline approach has been recently proposed by Zappa & Shepherd (2017 J. Clim.) as a way of characterizing the uncertainty in the atmospheric circulation response to climate change.

The next set of UK climate projections, UKCP18, will be available by the end of 2018. UKCP18 will contain probabilistic projections, as did UKCP09, but also (small) ensembles of simulations, at global, regional, and national scale. This project will develop drought-specific storylines using ensembles of simulations from UKCP18 and other sources, together with hydrological models. In this way the work will contribute to the evidence-gathering for the next UK Climate Change Risk Assessment.

TRAINING
The project is co-supervised by Dr Katie Smith at CEH Wallingford and the student will undergo a placement there for 6 to 18 months (with the length of the placement depending on the preferences of the student), as well as regular visits. CEH provides an exceptionally supportive atmosphere for students, whilst surrounding them with leading experts in ecology and hydrology. NERC-funded PhD students have access to CEH’s expansive staff training courses, such as programming, high performance computing, scientific writing and publishing, etc. As well as training courses, the student will have access to informal training at CEH from a large group of hydrology experts, as well as scientists working for the British Geological Survey who share the CEH Wallingford office. The student will gain knowledge on how the climate and geology of the UK drive a range of river flow regimes. This will complement the meteorological training gained at the University of Reading. The student will also receive assistance in learning computer programming skills, especially in the “R” language. They will be taught how to work within a Linux operating system in order to make use of the NERC JASMIN High Performance Computer Cluster for demanding computational tasks, as well as how to handle large data files and formats such as netCDF files. Katie Smith can provide one-to-one training in how to calibrate and run hydrological models, as well as how to conduct sensitivity and uncertainty analyses.

The student will also be welcomed into the EURO-FRIEND Low Flow and Drought network, a working group of European drought researchers, who meet twice annually to discuss progress and future directions.

To read more about this project please click on the following link: http://www.met.reading.ac.uk/nercdtp/home/available/desc/entry2018/SC201822.pdf