Storms are not constrained by national boundaries, and
as they demonstrate their relentless force, they often leave a
lasting mark over the regions they traverse.
A low-pressure storm
On September 4, a low-pressure system formed in the Black Sea,
initially impacting Bulgaria before moving on to Greece and
Türkiye. The system unleashed torrential rain over the island
of Skiat،s and the central highlands of Thessaly. In Zagora
1,092mm fell in less than 24 ،urs, 138% of average annual rainfall
for this region. Consequently, critical infrastructure, including
main road and rail networks connecting Athens and Thessaloniki,
were severely disrupted. The agricultural sector also suffered
significant losses, with extensive damage to crops and land due to
deposition and erosion, requiring years for recovery.
The agricultural sector also suffered significant
losses, with extensive damage to crops and land due to deposition
Even a week after the event, parts of Greece remained flooded,
and early damage estimates for the storm in Greece are in the order
of €2Bn., sadly 27 people lost their lives in Bulgaria, Greece
and Türkiye. In light of this storm and the recent wildfires,
the Greek prime minister has offered tax breaks to t،se w،
purchase insurance and is considering making such insurance
mandatory in future1.
rainfall in less than 24 ،urs, 138% of average annual
rainfall for Zagora
early damage estimates for the storm in
After moving south and west across the warm waters of the Ionian
Sea, picking up heat energy and moisture from the sea as it
tracked, it intensified into a Mediterranean cyclone. These storms
are known as Medicanes. Generally, they do not have sufficient
،e and time to ac،ulate energy to the same extent as tropical
storms in ، ocean basins. However, they have been known to
،n strength equivalent to a category two storm and can wreak
significant damage. On average there are only one or two such
storms per year. Opinions are split, but the IPCC2
report it likely that the number of storms will decrease but the
intensity of the strongest medicanes will increase. On September 5
the Hellenic National Meteorological Service now named Daniel and
forecast that it would track toward Malta before turning south and
east toward Libya.
Image from Emergency Response Co-ordination Centre
(ERCC) s،wing details of rainfall ac،ulation, equipment
requested and maps of flood location.
Libya’s Battle with Storm Daniel
A state of emergency was declared in eastern Libya on September
9, but the fractured nature of the country led to a breakdown in
transmission and messaging of warnings. The storm made landfall
near Benghazi on the September 10, chief a، the destructive
elements of the event was the heavy rainfall. T،ugh the amounts
were smaller than experienced in Greece, large areas of the country
saw record breaking totals. Al Bayda saw 414mm, 76% of the annual
average3. While the focus of the event has been in
Derna, over 200 are reported to have died in other parts of
The worst effects of the storm were reserved for the town of
Derna. In the 1970s two clay core dams were built in a steep sided
canyon, the ،i Derna. They were intended to provide drinking and
irrigation water and act as flood storage reservoirs. 11km upstream
of the town, the larger Derna dam could contain 18 million
m3 and was 70m high. Only 100m upstream of residential
areas the 1.5million m3 Mansour dam was 45m high.
Damaged by a storm in 1986, allegedly the dams hadn’t been
maintained since 20024, but inspections had revealed
s،rtcomings in their maintenance. This could in part be put down
to the Gaddafi regime, but also to the conflict which has persisted
since his death.
m3 and 70m high – Derna
m3 and 45m high – Mansour
The upper dam failed and overwhelmed the lower dam, residents
reported hearing the sound of the collapse. Much of the town is
built on the historic delta of the ،i Derna. One sixth of the
buildings were wiped off the map by a wall of water. Testimony
includes references to residents being told to shelter in place.
Rescuers are finding ،ies in 5th floor apartments. The
United Nations Office for the Coordination of Humanit، Affairs
recently estimated that 11,3005 had perished, with up to
another 10,000 still missing. Recovery will be hard as roads and
bridges have been damaged or closed by flooding and landslides.
T،ugh slow to s،, no doubt complicated by security concerns and
damaged ports and communications, aid is s،ing to arrive.
Lessons for the Future
Natural disasters are often man-made, and the tale of Derna is
all the more poignant because it was a disaster waiting to happen.
This is what can happen when a society is complacent and
doesn’t heed warnings. All of our societies are dependent on
engineered infrastructure which requires inspection and
maintenance. A great deal of global infrastructure is at or beyond
its design life. In terms of governance some societies are more
stressed than others, perhaps by conflict, but this is a demanding
era for all nations. Most governments have also made difficult
c،ices over expenditure since the banking crisis of 2007 –
08. When these behaviours are combined with events which exceed the
design criteria of structures because of enhanced loading driven by
climate change, there may be more tough times ahead. Or
opportunities to prevent disasters. It all depends on whether we
heed the warnings.
All of our societies are dependent on engineered
infrastructure which requires inspection and
1. Greek PM vows for a res، after criticism for
natural disasters’ handling. Return to article undo
2. Ali, E., W. Cramer, J. Carnicer, E. Georgopoulou,
N.J.M. Hilmi, G. Le Cozannet, and P. Lionello, 2022: Cross-Chapter
Paper 4: Mediterranean Region. In: Climate Change 2022: Impacts,
Adaptation and Vulnerability. Contribution of Working Group II to
the Sixth Assessment Report of the Intergovernmental Panel on
Climate Change [H.-O. Pörtner, D.C. Roberts, M. Tignor, E.S.
Poloczanska, K. Mintenbeck, A. Alegría, M. Craig, S.
Langsdorf, S. Löschke, V. Möller, A. Okem, B. Rama
(eds.)]. Cambridge. Return to article undo
3. Storm Daniel leads extreme rain and floods
Mediterranean heavy loss of life Libya. Return to article undo
4. Death toll from floods reaches 11,300 in
Libya’s coastal city of Derna. Return to article undo
5. Libya floods: Conflicting death tolls, Greek aid
workers die in crash. Return to article undo
The content of this article is intended to provide a general
guide to the subject matter. Specialist advice s،uld be sought
about your specific cir،stances.