The Copernicus Data Space Ecosystem offers immediate access to a wide range of open and free Earth observation data and services.
Copernicus Sentinel-1 unravels how landslides can reactivate - Sentinel Success Stories
Copernicus Sentinel-1 unravels how landslides can reactivate
Cloud-penetrating radar measurements from Copernicus Sentinel-1 are being used to understand the timing of landslides and what reactivates them.
As our climate crisis intensifies weather-related natural disasters, remote sensing data are proving to be an ideal tool for managing emergencies such as landslides.
However, in tropical areas, cloud cover often obscures the optical images taken by satellites as events unfold. This makes it difficult to understand what is triggering the landslides.
This is where the Sentinel-1 satellite from the European Union's Copernicus programme comes in, with its Synthetic Aperture Radar (SAR) data.
Landslides cause changes to the scattering properties of Earth’s surface and this effect can be detected by SAR even when the area of interest is obscured by cloud cover or darkness.
An earthquake on the island of Lombok, Indonesia, in 2018.
“We need to know at which point in the sequence each landslide happened, to better understand the triggering conditions of the earthquakes and help build hazard models,” says Katy Burrows, an ESA-based researcher.
An earthquake on the island of Lombok, Indonesia, in 2018.
The Cotabato - Davao del Sur earthquake in the Philippines in 2019.
And the 2021 earthquake-hurricane sequence in Haiti.
An earthquake on the island of Lombok, Indonesia, in 2018.
The Cotabato - Davao del Sur earthquake in the Philippines in 2019.
And the 2021 earthquake-hurricane sequence in Haiti.
In the Lombok earthquake sequence, there were four earthquakes in one month. Using optical data from Copernicus Sentinel-2, scientists can see landslide scars, but between some of the earthquakes most of the images are obscured by cloud cover.
“This is why we used Sentinel-1 data to penetrate the clouds. These data allowed us to see that many of the landslides moved during each earthquake, rather than failing once,” says Burrows.
The team's aim was to see the susceptibility of landslides throughout the earthquake sequence, so that the probability of failure in particular areas could be predicted. This is important information for communities dealing with natural disasters.
In the Lombok earthquake sequence, there were four earthquakes in one month. Using optical data from Copernicus Sentinel-2, scientists can see landslide scars, but between some of the earthquakes most of the images are obscured by cloud cover.
“This is why we used Sentinel-1 data to penetrate the clouds. These data allowed us to see that many of the landslides moved during each earthquake, rather than failing once,” says Burrows.
The team's aim was to see the susceptibility of landslides throughout the earthquake sequence, so that the probability of failure in particular areas could be predicted. This is important information for communities dealing with natural disasters.
They demonstrated that for large, favourably oriented landslides, InSAR coherence can be sensitive to reactivation and so could potentially be used in the future for cases where no cloud-free images are available.
Using the cloud-penetrating capabilities of Copernicus Sentinel-1 radar data, researchers can analyse landslide reactivation, providing invaluable insights for hazard modelling and disaster preparedness.
Would you like to learn more about this story?
Read full story
In the Lombok earthquake sequence, there were four earthquakes in one month. Using optical data from Copernicus Sentinel-2, scientists can see landslide scars, but between some of the earthquakes most of the images are obscured by cloud cover.