Libya floods: How Storm Daniel caused a river ‘tsunami’ that killed thousands

Over 30,000 displaced in devastating flooding making it the worst disaster of 2023 so far

More than 2,000 bodies were recovered in Libya and over 30,000 are missing and feared dead after a devastating storm said to be the deadliest climate disaster to have occurred this year so far.

The Mediterranean storm struck the conflict-stricken country’s eastern city of Derna on Tuesday. There are fears the toll could surpass 5,000 after floodwaters smashed through dams and washed away entire neighbourhoods.

The heavy rain and flooding in Libya were a consequence of remnants from a potent low-pressure system officially named Storm Daniel by meteorological services in southeastern Europe.

The devastation caused by the Mediterranean tropical-like cyclone,dubbed a “medicane”, which earlier caused catastrophic flooding in Greece, intensified further before unleashing havoc in Libya.

The startling death and devastation wreaked by the storm points to several factors, including the impact of the climate crisis in increasing the intensity of such storms, but also the vulnerability of a nation torn apart by chaos for more than a decade.

The country is divided by rival governments, one in the east and the other in the west. The result has been the neglect of infrastructure in many areas.

What caused Storm Daniel to become so deadly?

Before arriving in Libya, the storm went through an intensification process over the warm waters of the Mediterranean region. Climate scientists have been pointing out how warmer sea surface waters are making storms stronger, a phenomenon being observed around the globe.

The devastation can’t entirely be attributed to the climate crisis, “but we know there are factors that could be at play” with storms like Daniel that make it more likely, said Kristen Corbosiero, an atmospheric scientist at the University at Albany.

Daniel formed as a low-pressure weather system more than a week ago and was blocked by a high-pressure system dumping extreme amounts of rain on Greece and surrounding areas before inundating Libya.

Warming waters also are causing cyclones to move more slowly, which allows them to dump much more rain, said Raghu Murtugudde, a professor at the Indian Institute of Technology, Bombay and emeritus professor at the University of Maryland.

What’s more, he said, human activity and the climate crisis together “are producing compound effects of storms and land use”.

Karsten Haustein, a climate scientist and meteorologist at Leipzig University, said in a statement that Storm Daniel had dumped a whopping 440mm (15.7 inches) of rain on eastern Libya in a short time.

Ms Haustein cautioned that scientists haven’t had time yet to study Daniel, but noted that the Mediterranean has been 2 to 3 degrees Celsius warmer this year than in the past. And while weather patterns that formed Daniel would have occurred even without climate change, the consequences probably wouldn’t have been as severe.

In a cooler world, Daniel probably “wouldn’t have developed as quickly and rapidly as it did,” Haustein said. “And it wouldn’t have hit Libya with such ferocious strength.”

Experts said Libya’s crumbling infrastructure and poor early warning systems are to be blamed as well. Dams that collapsed outside Libya’s eastern city of Derna unleashed flash floods that may have killed thousands.

Poor forecasting and early warning systems also play a huge role in saving lives. But Libya, divided between two governments, has been mired in conflict for years that has left it highly vulnerable.

“To be effective, flood forecasting systems need good data on forecast rainfall and river levels, a network of well-maintained measuring instruments on the ground, and a clear plan to get people out of harm’s way,” said Dr Hannah Cloke, professor of hydrology at the University of Reading.

“The tragic death toll in Libya from catastrophic flooding that has decimated a city shows what can happen if any parts of this chain are not in place or don’t work properly.”

“The infrastructure could probably not cope, leading to the collapse of the dam,” he said, adding that human-induced rises in water-surface temperatures likely added to the storm’s intensity.

What is a Medicane?

Medicanes form once or twice a year in the Mediterranean, and are most common from September to January.

They’re not generally true hurricanes, but can reach hurricane strength on rare occasions, said Simon Mason, chief climate scientist at the Columbia Climate School’s International Research Institute for Climate and Society.

“Medicanes such as Storm Daniel are relatively rare, and tend to occur more frequently in the western portion of the Mediterranean Sea than the arid Libyan coastline,” explained Liz Stephens, professor in climate risks and resilience at University of Reading.

“Climate change is thought to be increasing the intensity of the strongest medicanes, and we are confident that climate change is supercharging the rainfall associated with such storms,” Dr Stephens said.

Where is the storm headed now?

The storm is now moving along the north African coast, with authorities in Egypt calming worried citizens by telling them that Storm Daniel had finally lost strength.

“No need to panic!” the Al Ahram newspaper wrote in its online English-language edition, Reuters reported.

Additional reporting by agencies