With record breaking amounts of rainfall, floods and storms in the past couple of months, the UK is well and truly underwater. But what about the future? Are more events like these on the horizon, and if so how should we best mitigate against these challenges? We explore some of the reports that have been released this month that look at these issues.
In June last year, the BES released its own report looking at the impact extreme events, such as flooding, could have upon freshwater ecosystems. It wasn’t too long to wait after its launch to see the impacts that flooding has had on the UK. It has been reported that December and January have seen exceptional periods of winter rainfall in England and Wales not seen for 248 years. And more rain is forecast to be on the way, with PM David Cameron warning that victims of the floods are ‘in it for the long haul’. What’s more, there have been increasing comments that these events can be linked to climate change, but just how true are these claims?
In mid-February, the MetOffice and Centre for Ecology and Hydrology released a report detailing the extremity of these floods and whether climate change could have contributed to their frequency and impact. Within the report there are some staggering figures and stats about the record breaking nature of this recent UK weather. December and January, for the South and South East of the UK, have been the wettest since records began since 1910. Similarly, Scotland experienced its wettest December since 1910. High wind speeds have resulted in coastal damage and a storm surge in the North Sea in early December that also coincided with one of the highest tides of the year.
The report further explores these recent trends and puts them in context with wider global trends. In Canada and USA, extreme cold weather was experienced at a similar time, and just in the US it is estimated around 200 million people were affected. These extreme events experienced both in the US and UK can be linked to observed changes in the jet streams over North America and Pacific Ocean, which themselves experienced perturbations at similar times. Added to these were changes in the polar regions, and these combined alterations are thought to have impacted the weather in the UK, such as increasing the severity of storms and increasing amount of rainfall. However, there is uncertainty linking particular events to these changes, although the authors note that it is highly likely that these factors are all interlinked.
But what about climate change? The report argues that three factors should be considered when asking how climate change could be affecting UK weather: 1) how does sea level rise affect coastal flooding 2) number and strength of storms and 3) rainfall events. There are a number of lines of evidence that could suggest climate change is linked, but this is uncertain. Whilst the number of storms has not increased since 1971, the severity and intensity of those has. With regards to rainfall, there are reports that extreme daily rainfall events have increased in their frequency and intensity. However, attributing these changes to climate change requires more modelling and simulations to be run and more research is needed to detect changes in storminess and rainfall events.
But if these extreme events are to increase in their frequency or severity into the future, how can we address these challenges? Our own report highlights the increasing need to invest in natural flood management rather than hard engineering techniques, and sustainable drainage systems in urban areas can help relieve surface run-off. A new report out this week from the Chartered Institute for Water and Environmental Management explores the issue of dredging, which has been highlighted by the Government and media in recent weeks as being a solution to the flooding problem. However, whilst the report notes that dredging could be part of the answer for flood mitigation, it is not the only solution that should be considered. Dredging can have significant impacts upon both ecological and hydrological systems and can even increase flood risk in some areas. Therefore caution should be taken when using this approach, and the report encourages for dredging to be used as part of a wider range of mitigation measures.
Into the future, it is difficult to predict how and when events such as those being experienced at the moment will occur again and the severity their impacts will have. However, there is increasing research being done in this area and political attention is high at the moment to these issues. The biggest key is to ensure that rash actions aren’t undertaken in response to these floods; a strategic approach is needed not only for social and economic recovery, but also for resilient and healthy ecosystems.