In this monthly feature, we span the globe to examine Our Changing Landscape with a time series of medium-resolution PlanetScope satellite imagery. The PlanetScope constellation dates back to 2016 and collects hundreds of millions of square kilometers of four and eight-band 3-meter imagery daily! In November, we looked at the devastating wildfires that swept the Lahaina area of Maui, Hawaii. This month, we’re traveling to Derna, Libya to examine the tragic flooding that recently inundated the area.

The PlanetScope Microsat Constellation

Click on the image above to see an animation of 3-meter natural color PlanetScope imagery collected over Derna, Libya on August 31 and September 15, 2023. In the history of this series, we have covered multiple floods but none of them have displayed the intensity of mother nature as this animation of the September 11th dam breached and subsequent flooding shows. In the September 15th image you can see how intense the flood waters must have been as they gouged out deep channels in the canyons to the south of Derna. And then within Derna, you can see that a wide swath of the center of town was literally wiped out as the flood waters made their way to the ocean. Just tragic – our hearts are with the residents, family and friends of Derna. (Images Courtesy: © Planet 2023)

PlanetScope is a constellation of more than 240 microsats referred to individually as Doves. Each Dove is able to collect up to 20,000 square kilometers (sq km) per day of 3-meter (m) 4-band multispectral (i.e. blue, green, red and near-infrared [NIR]) imagery; and newly launched SuperDoves collect 8-band multispectral adding in valuable red-edge spectral data. Across the constellation, PlanetScope is archiving more than 200 million sq km of medium-resolution imagery a day, making it the go to source for daily imagery over most locations. This massive archive dates back to 2016, offering the most complete and continuous record of spatial data on the planet since the start of the constellation’s ongoing launch schedule. Collecting 3-meter multispectral imagery is the equivalent of ‘high-resolution’ multispectral data imaged by a 75-centimer (cm) satellite (as this satellite would feature 75-cm panchromatic and 3-m multispectral), making PlanetScope an extremely competitively priced option at just $2.25 per sq km. With well registered images and nearly daily collections of most locations, PlanetScope is the ideal imagery source for this current-events focused series, Our Changing Landscape.

September 2023 Derna, Libya Flooding

On September 10th and 11th of this year, the coastal city of Derna, Libya faced a harrowing natural disaster as torrential rains triggered severe flooding, leaving a trail of devastation in its wake. Derna, situated along the Mediterranean coast, typically enjoys a moderate climate, and the unexpected deluge was a stark departure from its usual weather patterns.

The flooding was caused by Mediterranean Storm Daniel which passed through Libya and dropped the equivalent of eight months-worth of rain in one weekend, destroying nearly 25% of Derna. The destruction was caused by massive amounts of mud and water released with the collapse of two dams upstream (from the pressure of Daniel’s precipitation) – with the actual collapses happening in the early hours of September 11th.

Climate scientists and meteorologists point to the changing climate, which has led to increased sea temperatures in the Mediterranean, as a key factor in the flooding. Warmer waters can fuel more intense rainfall; and in this case, it resulted in the heavy downpours that caused such widespread flooding.

The consequences for Derna and its citizens were devastating. Streets turned into rivers, homes were inundated, and livelihoods were disrupted. Tragically, over 4,000 lives were lost and more than 10,000 people were missing after the heavy rains. According to counts given by the International Organization for Migration, nearly 40,000 people were displaced by the storm, three quarters of which were displaced specifically from Derna. The community has faced significant economic and emotional hardships in the aftermath of the flooding.

The September 2023 flooding in Derna underscores the urgent need for communities to increase their preparedness and resilience in the face of Climate Change and the unpredictable weather events it spurs. As communities worldwide grapple with the realities of a changing climate, events like the flooding in Derna highlight the critical imperative of both adaptation and mitigation strategies to protect lives and livelihoods in an increasingly uncertain environmental landscape. It is incumbent upon the global community to take swift and decisive action to mitigate these impacts and protect the most vulnerable among us.

If you would like to contribute financially to the restoration efforts in Derna, donations may be made here.

If you would like to find out more about using 3-meter PlanetScope imagery for your academic studies, engineering projects or any landscape analysis, let us know at sales@apollomapping.com or (303) 993-3863.