Over a hundred thousand people have been displaced by wildfires in California. What neighborhoods and properties have been damaged, what forests have burned, and what has been spared?
Maxar Technologies, a trusted partner and innovator in Earth Intelligence and Space Infrastructure, has partnered with Mapbox to launch a new map to share shortwave infrared (SWIR) imagery of the wildfires burning across California. SWIR can penetrate smoke unlike all other optical sensors, so this provides a way to ‘see through the smoke’ and detect and measure what areas have burned or not.
Using the map
The new SWIR imagery map makes it easier for displaced Californians to monitor the homes they had to leave behind. Maxar will be adding new SWIR imagery as it becomes available. The SWIR map will be available under the Creative Commons Attribution Non-Commercial 4.0 license (CC BY-NC 4.0) for the duration of the 2020 fire season; Maxar’s Open Data Program is also releasing pre-event, during event and post-event image strips of the wildfires under the same license. Requests for direct, commercial access to the imagery should be directed to Maxar.
The map loads the most recent images first; users can switch map layers to explore previously collected imagery. The search bar on the web map makes it easier to zoom to specific locations and addresses.
The colors of SWIR imagery are different from those of typical satellite imagery. In SWIR images, active fires and hot spots glow orange and yellow. Burned vegetation appears in shades of dark orange and rust colors. Healthy, unburned vegetation appears in shades of blue.
Traditional high-resolution satellites measure the red, green, blue, and sometimes near-Infrared (NIR) wavelengths of light, with the first 3 being those that humans see (350–700 nanometers), and NIR (750–900 nm) going just beyond what we see. Maxar’s SWIR sensor, the only commercial sensor in orbit, measures wavelengths between about 1100 and 2400 nm, detecting things like heat, materials on the ground (both manmade and natural), and soil moisture. Different surfaces have specific reflectance properties that SWIR can detect, making it a valuable tool in remote sensing applications. In this case, SWIR is able to penetrate through wildfire smoke to still capture the Earth’s surface, providing a detailed view of the ground, including burned areas and active fire zones.