Natural disasters are a growing concern in our world as their frequency and magnitude have increased exponentially. As these disasters hit more populated areas affecting more and more people, it creates an urgent need for effective tools to monitor and manage these unpredictable events. With the technological advances in satellite imagery, unmanned aircrafts, and remote sensing techniques, monitoring and managing events like floods, earthquakes, tsunamis and forest fires has become not only possible, but quite doable.
As satellites improve and advance, it is necessary for the analytic capabilities that extract information from their imagery to evolve as well. With the increase in higher resolution sensors, the number of spectral bands available, as well as the revisit rates of these satellites, the advanced analytics in ENVI have become an invaluable tool for disaster management.
I have been working closely with an amazing group at Deimos Imaging – an Urthecast company – to prototype and develop automated workflows for disaster response, in particularly flood mapping and monitoring. By processing Deimos-2’s very high-resolution imagery with ENVI, a user can quickly extract product-ready solutions for flood mapping, flood extents, feature extraction, and change detection using temporal data.
Below are two separate examples of how ENVI was able to utilize Deimos-2 high-resolution imagery in quick turnaround environments to get accurate answers following a disaster. The first example below is of a flood of the Mosul dam in 2017. As you can see from the before and after photos, there was a large amount of flood water and debris that expanded the Snake River over a period of time, displacing residents and causing millions of dollars in damages.
The second example below is the earthquake that recently happened in Palu, Indonesia. On September 28th, 2018 a magnitude 4.9 earthquake struck Palu causing major ‘soil liquefaction’ in areas in and around Palu, leading to mudflows that submerged many buildings. Using ENVI’s readily available tools, I was able to extract not only the sediment contaminated flood water, but also the relative depth of that water compared to what is was before.
As the number and severity of natural disasters continue to increase, so too will the need for effective ways to manage and monitor them. Deimos high-resolution imagery and ENVI’s analytics is one way to improve situational awareness of a natural disaster and provide actionable information to the right people, at the right time.