First Planet satellite images of the landslides in Malawi from Cyclone Freddy

Yesterday, I highlighted that Cyclone Freddy has triggered multiple damaging landslides in Malawi.  I have started to look at the Planet imagery of the potentially affected areas, particularly in the area of Chiradzulu, which is reported to have been badly impacted.  This is an area that is heavily affected by cloud, so obtaining good imagery is not straightforward.  It is likely that it will be some days or even weeks before we get a full picture.

However, this is the Chiradzulu Forest Reserve, with an image collected on 19 March 2023.  The centre of this image is at about [-15.693, 35.161]:-

The area affected by landslides triggered by Cyclone Freddy in Chiradzulu Forest Reserve, Malawi. Image copyright Planet, used with permission, collected on 19 March 2023.

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For reference, this is the same area in an image collected before Cyclone Freddy, on 21 February 2023:-

The area affected by landslides triggered by Cyclone Freddy in Chiradzulu Forest Reserve, Malawi. Image copyright Planet, used with permission, collected on 21 February 2023.

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I have created a slider to allow the images to be compared easily:-

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The Planet satellite imagery shows multiple long run out flows, most of which appear to have initiated as shallow landslides on the higher slopes.  Many have involved multiple landslide sources that have merged in channels to form more destructive landslides on the lower slopes.  In several locations the landslides have impacted the settlements, as shown in this area of the image:-

One of the areas most affected by landslides triggered by Cyclone Freddy in Chiradzulu Forest Reserve, Malawi. Image copyright Planet, used with permission, collected on 19 March 2023.

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There is also evidence of landslides in other parts of the area too.  On the western flanks of Mount Soche to the south of Blantyre, there is the landslide shown below (the location is [-15.842, 35.018]).  Whilst the image is affected by cloud, and the landslide is on the very edge of the area captured, it appears that this landslide has run out through the urbanised area:-

A landslide triggered by Cyclone Freddy on the flanks of Mount Soche in, Malawi. Image copyright Planet, used with permission, collected on 19 March 2023.

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Whilst the imagery is insufficiently good to be sure, I am reasonably confident that there are further landslides in Malabvi Forest Reserve, located at [15.846, 35.136].  This post on Facebook would seem to support that assumption.

Whilst we await better imagery, it is clear that this area has been affected by dreadful landslides.  Sadly, this is not the first time.  Loyal reader Yannick Thiery from BGRM in France kindly contacted me to note that a similar landslide was triggered near to Chiradzulu by Cyclone Idai in March 2019.  The location was reported to be [-15.683, 35.674].

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Reference and acknowledgement

Planet Team (2023). Planet Application Program Interface: In Space for Life on Earth. San Francisco, CA. https://www.planet.com/