In September 2023, a devastating cyclone struck the northeastern coastline of Libya, particularly affecting the city of Derna. The event led to the loss of thousands of lives and displaced approximately 40,000 individuals. Satellite images underscored the considerable extent of the devastation, categorizing this storm as one of the deadliest and most uncommon meteorological occurrences in Africa.
Intense flooding in Derna’s port area resulted in the destruction of infrastructure and the washing away of entire residential areas into the sea.
During the early days of September 2023, an uncommon cyclonic event in the Mediterranean led to significant flooding in cities situated along Libya’s northeastern coast, leading to a multitude of casualties. Among the worst affected was Derna, a port city with a population of nearly 90,000, where extensive damage and flooding were recorded.
On the 10th and 11th of September, more than 100 millimeters (approximately 4 inches) of rain were registered in Derna. The city is positioned at the terminus of a prolonged, slender valley, known as a wadi, which remains arid except during periods of rainfall. The flooding caused the collapse of two dams situated along the wadi. The subsequent failure of the second dam, situated merely one kilometer inland from Derna, released floodwaters ranging between 3 to 7 meters (10 to 23 feet) in height, wreaking havoc across the city. According to media reports, the surging waters annihilated roadways and swept away whole residential sections into the sea.
Imagery obtained from satellites, specifically the Operational Land Imager-2 onboard Landsat 9, captured views of the northeastern Libyan coastline on August 25, 2023.
The visual records on this page present a comparison of the city’s condition prior to and following the cyclone. An image acquired by Landsat 9’s Operational Land Imager-2 (OLI-2) on September 18 revealed the eroded banks of Wadi Derna near its confluence with the Mediterranean. The offshore water appeared notably murkier compared to the image captured on August 25 by Landsat 8.
An initial assessment by the United Nations Satellite Center (UNOSAT) suggested that around 3,100 structures in Derna suffered damage due to the flooding. As per data from the UN International Organization for Migration (IOM), about 40,000 individuals were displaced nationwide, with 30,000 of those specifically from Derna.
Cyclonic systems resembling tropical storms, colloquially termed “medicanes,” are relatively rare in the Mediterranean, occurring maybe once or twice annually, primarily in the autumn months. According to experts at Yale Climate Connections, this storm was recorded as the most lethal in Africa’s documented meteorological history. Recent scientific evaluations from World Weather Attribution suggest that the rainfall received during this event was an extraordinarily rare occurrence, ranging from a one-in-300 to a one-in-600-year event.
The satellite images utilized in this analysis were procured by Lauren Dauphin, utilizing Landsat data supplied by the U.S. Geological Survey.
Table of Contents
Frequently Asked Questions (FAQs) about Deadliest Cyclone in Libya
What areas were most affected by the September 2023 cyclone in Libya?
The most affected area was the northeastern coast of Libya, particularly the city of Derna. The port city experienced significant flooding and infrastructure damage, leading to devastating consequences for the local population.
How many people were displaced and affected by the cyclone?
Approximately 40,000 individuals were displaced due to the cyclone, with 30,000 specifically displaced from the city of Derna. Thousands of lives were lost as a result of this unprecedented weather event.
What is the significance of this cyclone in the context of Africa’s weather history?
According to experts, this cyclone is one of the deadliest and most uncommon weather occurrences in Africa’s documented meteorological history. Scientific evaluations suggest that the rainfall during this event ranged from a one-in-300 to a one-in-600-year occurrence.
How did the cyclone impact the infrastructure in affected areas?
The cyclone led to the collapse of two dams along a long, narrow valley called a wadi near Derna. Roads were destroyed, and entire residential areas were swept out to sea. Satellite assessments indicate that around 3,100 structures in Derna were damaged due to the flooding.
What sources provided satellite imagery of the cyclone’s impact?
Satellite imagery capturing the extensive damage was acquired by the Operational Land Imager-2 onboard Landsat 9 and Landsat 8. These images were instrumental in assessing the degree of destruction and were utilized in scientific and humanitarian assessments.
What organizations have been involved in the damage assessment and relief efforts?
The United Nations Satellite Center (UNOSAT) and the UN International Organization for Migration (IOM) were key organizations involved in the initial damage assessment and relief activities for the displaced population.
What are “medicanes” and how often do they occur?
“Medicanes,” or cyclonic systems resembling tropical storms, are relatively rare in the Mediterranean, developing perhaps once or twice a year. These systems typically form during the autumn months.
Who supplied the Landsat data used in the analysis?
The Landsat data used for the analysis was provided by the U.S. Geological Survey. The images were procured by Lauren Dauphin and have been crucial in understanding the scale of the disaster.
More about Deadliest Cyclone in Libya
- UN International Organization for Migration: Cyclone Impact in Libya
- United Nations Satellite Center: Preliminary Damage Assessment
- NOAA: Mediterranean Cyclones (“Medicanes”)
- Yale Climate Connections: Historic Weather Events in Africa
- World Weather Attribution: Extreme Weather Event Analysis
- U.S. Geological Survey: Landsat Data Information
- NASA Earth Observatory: Satellite Imagery of Libyan Cyclone
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8 comments
Good to see UN organizations stepping up for the damage assessment and relief. It’s crucial to get this right for future preparedness.
i live near Derna and it was horrifying. Never seen anything like this in my lifetime. We need international help, ASAP.
Medicanes are rare but look what they can do. Weather systems are becoming more unpredictable by the day.
Honestly, this is heartbreaking. Where was the preparedness? we’ve got to do better, people.
The Landsat data and Satellite imagery really puts it into perspective. Makes you realize the power of nature.
Thousands of lives lost and 40,000 displaced, this is an emergency. Where’s the international outcry? We need action, not just words.
a one-in-600 year event?? This is scary stuff. Climate change isn’t a joke, it’s literally killing people.
Wow, this is truly a wake-up call. Cant believe the scale of the disaster. Our thoughts are with everyone affected.