University of Southampton: International project to understand drivers of global flood hazard and risk supported by major NERC funding

Experts at the universities of Southampton and Hull are leading a new £3.7m project which aims to revolutionise our understanding of the drivers of flood hazard and risk globally.

Working along with seven other UK universities (Birmingham, Brighton, Bristol, Durham, Exeter, Oxford, ad Reading), as well as multiple national and international end-user organisations, the team has been successful in winning major grant funding from the Natural Environment Research Council (NERC).

The new project, titled EvoFlood, aims to improve the capability of Global Flood Models (GFMs) – state-of-the-art computer models used to simulate the probability of flooding across the Earth – and then apply them to understand how flooding will change in the coming decades.

Professor Steve Darby, who is based in Southampton’s School of Geography and Environmental Science and Professor Dan Parsons at the University of Hull are the co-Principal Investigators on the project.

Professor Darby said: “As our climate changes and as growing populations encroach onto the world’s floodplains, more and more people are becoming exposed to flooding.

“Every year, on average around 300 million people globally are affected by flooding, with the economic losses exceeding $60bn.

“It is essential that we can accurately simulate the risks posed by flooding so that people’s lives and livelihoods can adapt to, and be protected from, the devastating impacts of floods.”

Globally, nearly one billion people are potentially exposed to the risk of flooding. Faced with this huge societal challenge, there is an urgent need to predict how flood hazard and exposure will change in the years and decades to come.

Existing state-of-the-art Global Flood Models (GFMs) are used to simulate the probability of flooding across the Earth, but they are not without their limitations.

Dr Julian Leyland, Associate Professor in Geography at Southampton, is a co-investigator on the project. He explained: “Existing models do not represent river channels and floodplains in enough detail, in effect they are treated as ‘static pipes’ that remain unchanged over time. But we know that river channels change through time, for example becoming shallower if they silt up or becoming wider if their banks erode. This means a river’s capacity to contain a given flood also changes over time; existing models which neglect these processes therefore make poor predictions in the long term.”

The EvoFlood team will also use the latest advances in cell phone and satellite technologies to track shifting populations. Professor Andy Tatem, Director of Southampton’s WorldPop program, is also a co-investigator on the project. He said: “By combining predictions of flooding from our new models with WorldPop’s unique global population datasets, EvoFlood will also provide a greater understanding of how communities are exposed – and respond – to flood events.”

Overall, the EvoFlood project will address a number of key questions, including:

What is the relative importance on flooding of changes in the climate versus changes in river shape?
How will global flood hazard and risk change in the future?
What does this mean for the functioning of Earth’s complex floodplains which are corridors of life across the globe?
How do populations respond to flooding, and how can this knowledge be used to inform societal response in the future?
The outputs of the project, such as new flood hazard and risk maps, will be shared on open platforms, accessible to all, benefiting scientists, policy-makers, humanitarian agencies and societies across the globe.

The EvoFlood team is partnering with a wide range of key stakeholders to ensure that the work will make a positive societal impact.

Sue Manson, Principal Scientist at the Environment Agency, said: “The Environment Agency is pleased to be a Project Partner supporting the EvoFlood Project, which aims to develop a new generation of global scale flood models.

“We support the aims of the research programme which is committed to developing practical learning that will benefit current and future generations and I look forward to working with the project team.”

Mark Fletcher, Global Water Business Leader at Arup, said: “The EvoFlood research programme is committed to developing practical, innovative and sustainable learning and knowledge for the benefit of existing and future generations.”