The deadly flooding resulted in at least 218 deaths in Germany and Belgium, and damaged dozens of homes and buildings in the region. What prompted this disaster is directly linked to how humans are conducting themselves in the natural habitat. The flooding is caused by global climate change and will continue to worsen, with more frequency and severity unless we begin to take this much more seriously.

Why are some European countries much more susceptible to this flooding and what can we really do to make these floods less severe? Is it possible for reforestation to slow down the water flow and maybe stop some of the flooding completely? The answers to these questions are not easy or simple, and not the same for every country or even every town within a country. This makes the solution to climate change flooding much more complex.

A new study from the World Weather Attribution shows that European countries are nine times more likely to be affected by devastating floods as the climate change risk increases. The study was undertaken by 39 researchers from Germany, Belgium, The Netherlands, Switzerland, France, Luxembourg, the USA, and the UK. The researchers used peer-reviewed scientific methods to examine how human-induced climate change affected rainfall events in Europe this summer. In the end, the researchers from the study found out that climate change intensified the amount of rain that fell in one day in summer by 3-19 percent as the possibility of heavy rainfall in Western Europe is the outcome of human induced climate change.

Climate change increases the amount of heavy rainfall, which increases the flow into the European rivers, which then impacts the riverbanks and soil surrounding the rivers until they burst their banks. Higher global temperatures create more energy in the Earths system. Higher ocean levels and air temperatures increase evaporation which creates clouds. When the temperature is higher, these clouds can hold more moisture content and therefore drop a months’ worth of rain in two days which the vegetation and the rivers can’t handle. Unfortunately, more extreme flooding must be expected if temperatures continue to rise, which will lead to many more communities affected by floods and rising water levels. So, the question has to be asked; how can we identify the risk so climate change can be managed more effectively?

Deforestation is a big part of the problem as soil has a high water-holding capacity when there is vegetation. This reduces the risk of floods during heavy rainfall. Without these trees and plants, the soil will, over time, lose its fertility and its ability to hold onto water. Trees not only moderate climate, but act as water reservoirs for rivers. The planting of trees around rivers could reduce the height of flooding by up to 20%, though there still needs to be a strategy. For instance, foresting the area around a stream as it leads into a river can help as the trees will slow down the water
before it reaches the main river therefore reducing the water flow to a more manageable level. This happens by the trees, shrubs and deadwood along the riverbanks holding back the water.

The leaves of trees also help to slow down raindrops before they reach the ground by simply just being in the way, and an estimated 30% of these raindrops evaporate away. This means less water on the ground and helps reduce soil erosion. Water penetrates deeper into the soil, and at a faster rate around and under trees thus creating less surface run-off.

Something very interesting is that trees don’t have to be planted into the ground to reduce flooding. According to the Woodland Trust UK, “Wood dams and deflectors are carefully placed and individually designed as a flood prevention measure. These dams can be used to direct water into preferential areas, increasing temporary water storage and slowing down the flow of water.”

It is crucial for Western Europe (and the world) to invest in replanting natural forests as a way of restoring balance and helping to combat global climate change. If we concentrate on mitigating climate change and reducing it, and use money on this, in the long run the emotional and financial costs will be much less. Everyone from governments, businesses and individuals need to be prepared for these extreme weather events and we must all work together to reduce greenhouse gas emissions, so we can begin to control the rising temperatures while this is still possible. Reforestation and land restoration will help as they absorb CO2 and can reduce the impacts of extreme weather.

COVID-19 showed how quickly (some) governments could react to a worldwide crisis so why should climate change be any different!

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