Expert comment: Storm Christoph severe flooding becoming 'the norm'
22 January 2021
Dr Linda Speight, a hydrometeorologist at the ºÚ¹Ï³ÔÁÏÍø, said:
"After a particularly wet start to the year, Storm Chistoph bought record breaking rainfall totals for northern England and parts or Wales. Reflecting the classical characteristics of a winter storm it was the persistent rainfall over several days that led to flooding with many places experienced continuous rain for three to four days.
"There is a finite amount of space within our river systems. The volume of water that is produced by heavy, persistent rain over large areas simply cannot fit. As we’ve seen over the past few days, there is nowhere else for the water to go except for onto the floodplain.
"The heaviest rainfall has now passed. The places where river levels are still rising are the bottom of our largest river system which always take several days to respond. Today we have seen flood barriers deployed along the River Severn and River Wye, and flood peaks are expected in these rivers over the weekend.
"After that, much rain the ground will remain wet for some time. River levels will remain high and will respond quickly to further rainfall. Luckily the short-term forecast is for cold rather than wet weather.
"We cannot prevent this type of flooding. We can build flood defences around our towns and properties to attempt to keep the water out but there is a limit to what can be done in the face of such large volumes of water. As a country this year we have valued our access to water and open space more than ever. However, we still need to get better at accepting that sometimes water needs space too. For those communities and individuals that have to share their space with the water this is not an easy ask.
"Flood forecasting is an essential tool for flood risk management. Effective forecasts enable organisations and communities to take proactive actions to reduce the impacts of flooding when it does occur. Effective flood forecasts require good underlying models and clear communication to ensure the right people get the right message at the right time. The Environment Agency did this very well in the run up to Storm Christoph. In Dewsbury they even had time to set up Covid-secure evacuation centres and identify the most vulnerable people in advance."
Dr Jess Neumann, a hydrologist at the ºÚ¹Ï³ÔÁÏÍø, said:
"Whilst it is not possible to directly attribute one flood event to climate change, we know that as our climate warms, the atmosphere is able to hold more moisture which can lead to more intense rainfall and flooding.
"Large scale flood events that affect multiple areas of the UK are happening frequently - in just a few years we've experienced Storm Dennis, Storm Ciara and Storm Desmond which have all caused significant flood damage - and this will likely become "the norm" in future years.
"Climate change is not the only factor to consider. Exactly where the rain falls, the current conditions of the land surface, characteristics of the wider catchment and the location of 'at risk' communities are all important for predicting the nature of a potential flood event.
"People are and will remain at risk. Policies and actions need to work with local communities and consider what will be the most effective steps for mitigation and resilience. There is rarely a 'one-fix solution', but a combination of approaches including long-term and temporary defences, natural flood management and redesign of towns and cities will be needed."
Professor Hannah Cloke, a hydrologist at the ºÚ¹Ï³ÔÁÏÍø, said:
“It is a sad fact that we have brought some of the awful events this week on ourselves by building on flood plains and development policies that make the landscape less able to cope with large amounts of water arriving all at once.
"We are seeing more and more homes at risk from flooding in the UK, and Storm Christoph has issued a reminder of just how costly it is to ignore this risks and fail to plan properly.
“Flooding tears people from their homes where evacuations are necessary, and then tears their homes from them by causing long-lasting damage. The financial and emotional impacts of Storm Christoph are not over, with more rain set to sweep in from the Atlantic next week.
"More downpours falling on top of saturated ground and already high river levels will surely mean more rivers bursting their banks and causing more devastation to communities.â€
Phiala Mehring, flooding impacts researcher at the ºÚ¹Ï³ÔÁÏÍø, said:
"The pictures in the media about recent flooding are only a snapshot of what flooding is to the communities it impacts.
"Water in your home is just the start of flooding. Flooding seeps into every facet of life. You fear rain, you can’t go on holiday and leave your home alone in case the flood waters return, your lose your sense of home as a safe and secure place to live, you constantly check river level, streams, becks and drains (you become a drain spotter), you feel isolated, supported, alone (and often you are after the blue flashing lights have left the scene), you fight to get flood mitigation and alleviation schemes put in. Your whole life revolves around not flooding again.
"In recent years flood policy has made some minor moves towards understanding what flooding is to flood communities. However, the emphasis still remains on costs and financial benefits and mostly overlooks the very human and long terms impacts of flooding.
"Flood risk management needs to change, it needs to include flood communities in the decision making processes and use their expertise and experience in creating better funding models. In essence, flood communities need to be at the heart of flood risk management and policy needs to move from a financial and numerical definition of ‘flood impact’ to a more human construction including the long-term life impacts of flooding.
"Until flood risk management and flood policy understands this, we will never be able to manage flooding effectively and we will continue to let flood communities down."