While rain this time of year isn’t unusual, it’s the intensity of the downpour that has set off alarm bells among experts. They suggest a combination of factors has led to the deluge in the countries. Here is a look.
Heavy rains have hit France, England, Netherlands and Germany for more than two weeks, causing rivers to burst their banks in many areas, flooding homes and prompting evacuations.
While rain this time of year in these regions isn’t unusual, it’s the intensity of the downpour that has set off alarm bells among experts. They suggest a combination of factors, including global warming, rising sea levels, and ageing flood defence systems have led to the deluge in the countries.
Here is a look at the situation.
What is happening?
In France, the northern region has been the worst affected as 189 municipalities of the Pas de Calais department witnessed flooding. Till January 4, at least 1,299 homes had been damaged and a total of 371 people had been evacuated by the local authorities.
Widespread deluge has impacted central England — in Nottinghamshire County, officials declared a “major incident” due to flooding along the Trent River last week. In London, a landslide and flood waters disrupted train travel and around 50 people had to be evacuated because of rising water in the eastern part of the city. The flooding has come just days after the country’s large areas were battered by Storm Henk.
Meanwhile, in Germany, officials declared emergencies in several regions as high-running rivers flooded villages and farmland. In the Netherlands, flood plains were inundated and residents in some towns around the Ijsselmeer inland sea near Amsterdam used sandbags to protect their homes, according to a report by the Canadian Broadcasting Corporation (CBC).
Why is it happening?
There are three factors at play here: rising global temperature, sea level rise, and outdated flood defence systems. Let’s look at each of them.
First, global warming. Scientists have known that as the planet gets warmer, there will be more frequent extreme rainfall. With higher temperatures, there is more evaporation from land, oceans and water bodies, which means a warmer atmosphere can hold more moisture — experts suggest for every 1 degree Celsius rise in average temperature, the atmosphere can hold about 7% more moisture. This makes storms more dangerous as it leads to an increase in precipitation intensity, duration and/or frequency, which ultimately can cause severe flooding.
El Nino — a weather pattern that refers to an abnormal warming of surface waters in the equatorial Pacific Ocean — also partly contributed to increasing the temperatures of oceans, causing more evaporation and ultimately, more rain.
The second factor is sea level rise due to which rivers frequently breach their banks to flood the adjacent areas. Take the example of northern France, where rising sea levels likely led to the recent deluge — between 1966 and 2018, sea levels at Pas de Calais rose by 4.4 cm, according to a report by Euro News.
Lastly, ageing flood defence systems have exacerbated the situation. The Euro News report noted that the outdated water management systems of France failed to tackle the large volumes of water that had entered the affected regions. Authorities had to get water pumps from the Netherlands to combat flooding.
Moreover, people, both in France and England, have built infrastructure like roads and buildings on floodplains, restricting the natural routes the water would have taken to get drained into the floodplain soils. As a result, the water ends up flooding certain areas.
What happens next?
The situation is bound to get worse. Studies have shown that as the planet gets warmer, storms would get more intense, causing heavier rainfall. The frequency of extreme weather events like floods is also expected to go up.
Steve Turner, a hydrologist at the UK Centre for Ecology & Hydrology, in an interview on Friday told Science Media Centre: “Future projections suggest the UK overall may experience wetter winters as well as summers that are hotter and drier than at present but with periods of more intense rainfall. Continued human-induced climate warming in future is likely to result in further increases in peak river flows, which will cause more severe flooding and impacts on people, property and public services.”
Therefore, there is an urgent need to improve flood defences, early warning systems and resilience measures to tackle the fallout of heavy rain.
Written by Alind Chauhan
Source: The Indian Express, 9/01/24
