What caused the flash floods in Spain and what was the response?

Flash floods caused by heavy downpours in eastern Spain swept away everything in their path earlier this week.

Before they could react, people were trapped in cars, houses and businesses. Many died and thousands lost their livelihoods.

Four days later, authorities found 205 bodies — 202 of them in the eastern region of Valencia, two in Castilla-La Mancha and one in Andalusia.

On Friday, they continued the search for an unknown number of missing persons.

Thousands of volunteers helped clear the thick layers of mud and debris that still covered houses, streets and roads, despite power and water cuts and shortages of some basic goods.

Some of the cars that were washed away in piles or crashed into buildings still had bodies waiting to be identified.

Here are a few things to know about Spain’s worst storm on record:

The storms centered over the Magro and Turia river basins, and in the Poyo riverbed, walls of water burst their banks, catching people off guard as they went about their daily lives, with many returning home from work on Tuesday evening.

In the blink of an eye, muddy water covered roads and railways and entered homes and businesses in villages on the southern outskirts of the city of Valencia.

Drivers had to hide on the roofs of cars, while residents tried to take cover in the hills.

Spain’s national meteorological service said the hard-hit region of Chiva received more rain in eight hours than in the previous 20 months, calling the deluge “extraordinary”.

By the time authorities sent cellphone alerts warning of the severity of the phenomenon and asked people to stay indoors, many were already on their way, working or covered in water in low-lying areas or garages that had become death traps.

Scientists trying to explain what happened see two possible links to climate change caused by human activity.

First, warmer air holds and then sheds more rain. Another is possible changes in the jet stream—the river of air above the ground that moves weather systems around the globe—that creates extreme weather.

Climatologists and meteorologists said the immediate cause of the flooding was a low-pressure storm system that moved from an extremely wavy and stalled jet stream. But the system was just standing over the region and pouring rain.

This happens quite often, which is why in Spain they are called Danas, the Spanish abbreviation for the system, meteorologists say.

In addition, there is the unusually high temperature of the Mediterranean Sea. According to Carola Koenig of Brunel University London’s Center for Flood Risk and Resilience, mid-August saw the highest surface temperature on record at 28.47C.

The extreme weather comes after Spain struggled with prolonged droughts in 2022 and 2023. Drought and flood cycles are increasing with climate change, experts say.

Spain’s Mediterranean coast is used to autumn storms that can cause flooding, but this episode was the worst flash flood in recent memory.

Elderly people in Paiport, the site of the tragedy, said Tuesday’s flooding was three times worse than the 1957 flood, which killed at least 81 and was the worst in the tourism region’s history.

This episode led to the diversion of the Turia River, which meant that a large part of the city was spared from these floods.

In the 1980s, Valencia suffered two other major events: one in 1982 that killed around 30 people, and another five years later that broke rainfall records.

This week’s flash floods are also Spain’s deadliest natural disaster in history, surpassing the flood that swept away a campsite along the Gallego River in Biescas in the northeast, killing 87 people in August 1996.

The management of the crisis, which the Valencian government classifies as level two on a three-point scale, is in the hands of regional authorities, who can turn to the central government for help in mobilizing resources.

At the request of Valencian President Carlos Mason of the conservative Popular Party, Socialist Prime Minister Pedro Sánchez announced Saturday the deployment of 5,000 more soldiers to join rescue efforts, clear debris and provide water and food over the weekend.

Mr Sanchez said the government would also send 5,000 more national police officers to the region.

About 2,000 soldiers from the military’s Emergency Response Unit, the army’s first force to respond to natural disasters and humanitarian crises, are currently involved in emergency work, along with nearly 2,500 gendarmes from the Civil Guard, who have carried out 4,500 rescue operations during the floods. and 1,800 national police officers.

As many victims said they felt abandoned by the authorities, a wave of volunteers took to the streets to help.

With brooms, shovels, water and basic food, hundreds of people walked several miles each day to deliver supplies and help clean up the worst-hit areas.

Mr Sánchez’s government is expected to approve a disaster declaration on Tuesday, which would allow quick access to financial aid. Mr. Mason announced additional economic assistance.

Valencia’s regional government has been criticized for not sending a flood warning to mobile phones until 8pm on Tuesday, when flooding had already begun in some places and well after the national weather agency had issued a red warning for heavy rain.