What to know about flash floods that killed over 200 people in Spain | Weather News

Five days after terrible floods devastated towns in eastern Spain and killed at least 214 people, frustration is growing over the government's response, despite Prime Minister Pedro Sanchez promising to “enhance” recovery efforts by deploying 10,000 soldiers and police.

Authorities in the hardest-hit Valencia province said on Sunday that hopes of finding more survivors are fading after muddy torrents of water destroyed towns and infrastructure and killed at least 211 people in the region, along with two others in Castilla La Mancha and one in Andalusia.

Al Jazeera's Sonia Gallego, reporting from Valencia, said authorities fear more bodies could be recovered from underground car parks.

The tragedy is already Europe's worst flood disaster since 1967, when at least 500 people died in Portugal.

Spain's King Felipe VI and Queen Letizia were due to visit the Valencia region on Sunday, Spanish media reported.

Here's what you need to know about Spain's deadliest disaster in living memory:

What was the state's reaction?

The management of the crisis, classified by the Valencian government as level two on a scale of three, is in the hands of the regional authorities, which can ask the central government for help in mobilizing resources.

At the request of Valencia's President Carlos Mazon of the conservative People's Party, Socialist Prime Minister Sanchez announced on Saturday the deployment of 5,000 additional soldiers to take part in rescue operations, clear rubble and provide water and food.

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

Mazon came under fire last year for his decision to dismantle the Valencia Emergency Unit (UVE), which was set up by a left-leaning predecessor to respond to emergencies such as floods and wildfires.

Around 2,000 soldiers from the Military Emergency Unit, the army's first response force in natural disasters and humanitarian crises, are already involved in the emergency response, along with around 2,500 members of the Civil Guard and 1,800 officers from the state police, who have together rescued 4,500 people.

Thousands of volunteers from different parts of the city also came to help with brooms, shovels, water and basic food items, deliver supplies and help clean up the hardest hit areas.

Al Jazeera's Gallego said there was still a “tremendous community effort” to help those affected by the floods, while authorities were “working as quickly as possible” to rescue survivors.

“It’s filled with mud all over the city,” she said, noting there are also concerns about the spread of disease.

What happened?

The storms were concentrated in the Magro and Turia river basins, creating walls of water in the Poyo riverbed that flooded the river banks and surprised people going about their daily lives on Tuesday evening and early Wednesday.

Spain's national weather service said the worst-hit Chiva region received more rain in eight hours than in the previous 20 months, calling the flooding “extraordinary.”

By the time authorities sent alerts to cellphones warning of the severity of the flooding and urging people to stay home, many were already out and about, working or covered in water in low-lying areas or underground parking lots, becoming death traps.

What caused these massive flash floods?

Scientists trying to explain what caused the disaster see two likely connections to human-caused climate change.

One is that warmer air stores and then releases more rain. The other is possible changes in the jet stream — the flow of air over land that moves weather systems around the globe — that produce extreme weather.

Climate scientists and meteorologists said the immediate cause of the flooding was a “truncated low-pressure storm system” that emerged from an unusually wavy and stalled jet stream. This system remained parked over the region and rain was pouring down heavily. According to meteorologists, this happens frequently and is referred to as DANA, the Spanish acronym for the system.

Another factor was the unusually high temperature of the Mediterranean. In mid-August, it had the warmest surface temperature on record at 28.47 degrees Celsius (83.25 degrees Fahrenheit), said Carola Koenig of the Center for Flood Risk and Resilience at Brunel University of London.

The high temperature increases the ability to produce water vapor, resulting in more intense rain.

The extreme weather event came after Spain struggled with prolonged droughts in 2022 and 2023.

Experts say drought and flood cycles are increasing with climate change.

Has this happened before?

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

Elderly people in Paiporta, at the epicenter of the tragedy, said Tuesday's floods were three times as bad as those in 1957 and claimed at least 81 lives.

This episode led to the diversion of the Turia watercourse, which spared a large part of the city from these floods.

Valencia suffered two other major DANA events in the 1980s, one in 1982 with about 30 fatalities and another five years later that broke rainfall records.

The recent flash floods also surpassed the devastation of the flood that swept away a campsite on the Gallego River in Biescas in the northeast in August 1996, killing 87 people.