Learning to live with floods and droughts

A panel discussion on Living with Floods and Droughts: Adapting to Hydro-Climatic Extremes was held at the School of Geography and the Environment on 1 December 2014, and brought together a number of water and climate experts in the field.

Dr Simon Dadson, School of Geography and the Environment, chaired the event and highlighted the huge impacts that floods and droughts can have in both developed and developing countries. Examples include the 2013/14 floods in the UK and the 2011 floods in Thailand which caused an estimated $43 billion in economic losses.

At the other end of the hydrological spectrum, a severe drought in 2008 led the city of Barcelona to import water in tankers from France. East African droughts in 2010/11 brought about a devastating humanitarian crisis which counted 260,000 deaths and 1 million refugees.

Dr Dadson invited the panel to reflect on how flood and drought risks might change under future scenarios of climate change, and what actions could be taken to adapt to these changes.

Professor Jim Hall, Director of the Environmental Change Institute, said that we have tended to cope with floods and droughts reactively in the past, with extreme events triggering policy action only after they have occurred.

However, he said that a transition is underway to a risk-based approach which bases decision making on a much broader range of possible events and consequences that might occur in the future. This “quiet revolution of thinking and methodology” in risk analysis means that we are better than ever equipped to live with floods and droughts, he said.

“The single most important asset we have to manage present and future risks from extreme floods and droughts is the long-term observational record” said Professor Rob Wilby from Loughborough University. He stressed the value of using historic records and information from climate models to understand the processes driving extreme events and how risks change through time.

Climate models can be used to predict future risks. However as Dr Richard Betts, Head of Climate Impacts at the Met Office pointed out, different models can produce widely varying results and it is impossible to test their accuracy. There is work to be done both in improving the science, and in improving the communication of uncertainties, he said.

Drawing on expertise in climate change adaptation in developing countries, Professor Declan Conway from the London School of Economics and Political Science reminded the audience that the adaptation process has many steps and the production of climate scenarios is just one step.

Professor Conway reflected on what lessons from climate change adaptation in the UK might be relevant for developing countries. In this country, legislation has played an important role in forcing institutions to assess and act on risks facing society. He also mentioned the importance of monitoring – of changes that are occurring now, the consequences of those changes, and the effect of adaptation policies.

Professor Mike Acreman of the Centre for Ecology & Hydrology said that natural ecosystems are completely adapted to floods and droughts as these events are all part of the natural cycle. Floods or droughts can only been seen as ‘good or ‘bad’ when considering how they impact human uses of the environment.

The natural environment can play a role in influencing the hydrological cycle, Professor Acreman said, but only on a small scale and to a limited degree. For example, restoring wetlands can help store floodwater and release it slowly during drier periods. Payments for ecosystem services may provide a mechanism to fund conservation and restoration of the natural environment to help combat future floods.