Future climate projections show a strengthening of the hydrological cycle with more droughts and floods expected. This means a higher likelihood of cascading drought-to-flood disasters. Recent examples are the Millennium Drought – Brisbane flooding in Australia, the California drought – Oroville spillway collapse in the US, or the 2017-18 drought in East Africa followed by floods that resulted in hundreds of deaths. These events resulted in large economic losses, casualties and displacements.
Studies on future risks analyse drought and floods separately. However, droughts allow ample time for impacts and adaptation, which influence hazard, exposure, and vulnerability of a subsequent flood. Drought and floods are caused by extremes of the same hydrological cycle and hence are correlated by dynamic feedback, strongly interlinked with human processes. Treating droughts and floods as independent phenomena, while ignoring their interaction with societal forces, leads to incomplete/distorted understanding of the processes that lead to the impacts experienced, and hence to possible underestimations of future risks.
In the PerfectSTORM (STOrylines of FutuRe ExtreMes) project, a group of researchers will study the risk of cascading hazards of flooding after drought, focussing on hydro-social feedbacks. The project aims to provide guidance on future management of drought-to-flood events to boost the positive impacts of above-average rainfall on drought effects while reducing its impacts.
A mixed-methods approach based on theory from data science, hydrological modelling, sociology, behavioural and cognitive sciences will be used to develop quantitative and qualitative storylines in four case studies. Qualitative storylines will be collected with narrative interviews and mental simulation workshops and will be edited and analysed. Quantitative storylines will be constructed through time series of hydrological and social data that will be analysed and modelled following socio-ecological modelling theory. These storylines will then be combined in an iterative way using innovative data visualisation.
The context-specific features of the developed storylines will then be compared and extrapolated on a global scale by exploring a range of global datasets through novel data analyses techniques. This will result in the identification of global types and hotspots of drought-to-flood events. Positive pathways for future management of drought-to-flood events in different parts of the world will then be explored.
The project can be summarised in three Work Packages:
- WP1 will improve understanding of hydro-social processes underlying past drought-to-flood events in case studies, through the development of PAST qualitative and quantitative storylines.
- WP2 will identify future drought-to-flood risks by developing FUTURE qualitative and quantitative storylines, based on mental simulation and socio-hydrological modelling.
- WP3 will simulate quantitative storyline at global scale to identify positive pathways for future management of drought-to-flood events.
PerfectSTORM is funded by the ERC Starting Grant awarded to Anne van Loon. The study is conducted in collaboration with Red Cross Climate Centre, social scientists, socio-hydrologists and modelling experts from Anglia Ruskin University, Uppsala University, Arizona State University, and Ashoka Trust for Research in Ecology & Environment.