Why have the floods in Europe been so deadly?

Devastating floods in Germany and other parts of western Europe have been described as a "catastrophe", a "war zone" and "unprecedented".

Why have the floods in Europe been so deadly?
The town of Ahrweiler on Saturday. Photo: picture alliance/dpa | Thomas Frey

With more than 160 people dead across Europe and the toll still climbing, many are asking: How did this happen and why has it been so bad?

Exceptional weather

“Masses of air loaded with water had been blocked at high altitude by cold temperatures, which made them stagnate for four days over the region,” Jean Jouzel, a climatologist and former vice-president of the Intergovernmental Panel on Climate Change (IPCC), told AFP.

Between 100 and 150 millimetres (four and six inches) of rain fell between July 14 and 15, according to the German weather service – an amount that would normally be seen over two months.

Europe has been hit repeatedly by severe flooding before, but this week has been “exceptional in terms of both the amount of water and the violence” with which it was dumped, according to German hydrologist Kai Schröter.

READ ALSO: More than 140 dead in German flood disaster 

Global warming?

Many European politicians have squarely blamed global warming for the disaster, while Germany’s far-right AfD has accused them of “instrumentalising” the floods to promote a climate-protection agenda.

“We cannot yet say with certainty that this event is linked to global warming,” Schröter told AFP, but “global warming makes events like this more likely”.

In technical terms, climate change means the earth is becoming warmer so more water is evaporating, which “leads to larger water masses in the atmosphere”, increasing the risk of intense rainfall, he said.

The IPCC has also said global warming boosts the likelihood of extreme weather events.

READ ALSO: How the extreme flooding in Germany is linked to global warming

Small rivers overwhelmed

The worst-hit areas have been those near small rivers or tributaries without flood defences that have quickly become overwhelmed by the volume of rain and burst their banks.

“The Rhine is used to floods” and cities along it have built protections, unlike the towns and villages along the region’s smaller rivers, Armin Laschet, head of the hard-hit North Rhine-Westphalia region, said.

“When rivers are slower and wider, the water rises less quickly and there is more time to prepare,” said hydrologist Schröter.

Lack of awareness

Local authorities have come under fire in Germany for not evacuating people soon enough.

“Forecasters… issued warnings, yet the warnings were not taken seriously and preparations were inadequate,” said Hannah Cloke, a professor of hydrology at the UK’s University of Reading.

Some residents were also simply unaware of the risks of such violent flooding, with dozens found dead in their cellars.

“Some victims underestimated the danger and did not follow two basic rules during heavy rainfall. Firstly, avoid basements where water penetrates.

Secondly, switch off the electricity immediately,” Armin Schuster, chairman of the BBK, a state agency specialising in natural disasters, told the Bild daily.

READ ALSO: Why have so many died in the German floods?

Urban planning

Some experts have pointed to the dangers of poor urban planning and the increasing amount of concrete at the heart of a heavily industrialised, densely populated region of Europe.

The affected regions had already seen unusually high rainfall in recent weeks, meaning the soil was saturated and unable to absorb the excess water.

When the ground is covered with man-made materials like concrete, the soil is less able to absorb water, increasing the risk of flooding.

“Urbanisation… has played a role. Would the toll have been as high 40 years ago?” Jouzel asked.

By Florian CAZERES

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What temperatures can we expect in Germany this week?

Parts of Germany will see another heatwave this week as temperatures soar.

What temperatures can we expect in Germany this week?

The German Weather Service (DWD) has predicted that the mercury will climb in some regions of to around 34C this week. 

“After low pressure ‘Karin’ gave parts of Germany rain, sometimes in large quantities, high pressure ‘Piet’ is now back in pole position,” said meteorologist Lars Kirchhübel of the DWD.

This high pressure zone will dominate the weather in large parts of western and central Europe over the coming days, the weather expert said, adding that it will reach Germany too. 

On Monday temperatures remained fairly cool across the country after a weekend of showers, but they are set to climb over the course of the week, particularly on Wednesday and Thursday. Forecasters predict it could reach 32C in Stuttgart and 33C in Cologne on Thursday. Locally, temperatures could reach 34C. 

However, from the Oder and Neisse rivers to the Erzgebirge mountains and southeast Bavaria, denser clouds and some showers are to be expected. This is due to a high-level low pressure system over the Balkan region, according to forecasters. Short showers are also possible in the Black Forest.

“In most of the rest of the country, high ‘Piet’ will be able to hold its ground,” said Kirchhübel.

READ ALSO: Heavy rain in Bavaria swells rivers, but flooding avoided

At the end of the week, thunderstorms are forecast but temperatures are expected to remain high. 

August in Germany ‘too dry’

According to the European Centre for Medium-Range Weather Forecasts, August as a whole – apart from a few areas in eastern Germany – will be too dry compared to the multi-year average.

The Black Forest, the High Rhine and the Allgäu to the Bavarian Forest, however, are not expected to have any major problems due to the high rainfall of the past few days.

“Looking at Rhineland-Palatinate, the southern half of Hesse, the western half of North Rhine-Westphalia and Lower Franconia shows a different picture,” said Kirchhübel. In the last 30 days, only about 10 percent of the usual level of precipitation fell in some places.

“At some stations, no precipitation at all has been measured in August,” added Kirchhübel, referencing Würzburg as an example.

Rainfall at the weekend caused the water in the Rhine river to rise slightly. In Emmerich, the water level reached a positive value again after the historic low of the past few days: in the morning, it showed three centimetres – an increase of six centimetres compared to the previous day.

The water level also rose by several centimetres at the other measuring points in North Rhine-Westphalia: in Cologne, the level rose to 80cm and in Düsseldorf to 38cm.

READ ALSO: Damaged freighter blocks traffic at drought-hit Rhine

Despite this encouraging trend, the Waterways and Shipping Authority said it did not expect a huge improvement in water levels in the foreseeable future due to more hot weather coming.