USA — The United States is not exactly unfamiliar with massive forest fires. In the last two years alone, two stunning megafires turned a grand total of nearly 350,000 acres of land to ash and dust. In the wake of such fires, it’s understandable that professionals expected to facilitate natural recovery would be a little overwhelmed. Thankfully, NASA is now stepping in, providing satellite information that is key for helping local ecosystems recover.
Just last year, a “megafire” known as the King fire swept across forests around Lake Taho, burning up an estimated 97,717 acres between the states of California and Nevada. Afterwards, experts looked to the skies for answers, gathering data from a host of NASA satellite instruments.
“In some areas of the King fire, you don’t see any green for miles and miles,” Carlos Ramirez, program manager of the USFS’s Remote Sensing Laboratory, said in a statement.
He and his colleagues had looked to extremely detailed maps based on the satellite imagery to determine this. These are maps so detailed that the burnt-out husks of each and every individual tree are visible, as seen by the Jet Propulsion Laboratory’s Airborne Visible/Infrared Imaging Spectrometer (AVIRIS). They also show heat emanating from the charred soil, as seen by the MODIS/ASTER Airborne Simulator (MASTER).
“It’s likely there are not going to be any viable seed sources where the fire was that intense,” Ramirez added. “With the AVIRIS data set, we get an inventory of living vegetation and the condition of it. That gives people in charge of putting together restoration plans an idea of where to focus their attention.”
Looking not only at the King fire, but the 2013 Rim fire that swept across an estimated 250,000 acres (1,000 square kilometers) near and in Yosemite National Park, Ramirez and his colleagues are learning what information is invaluable for recovery management.
As he mentioned, where to distribute new seed is one decision. Additionally, megafires often burn so hot that they turn even roots into broken lumps of char. This leaves soil beds lose and unstable, causing entire regions to become vulnerable to erosion and mudslides.
In the natural world, it would be acceptable to leave affected regions like this be, as nature will eventually retake the nutrient-rich soil of a fresh fire. However, when highways and other infrastructure are nearby, action must be taken to avoid disaster.
Sometimes, conservationists also become involved, worried that even a natural disaster could lead to the extinction of some already threatened species.
“Some of these high-severity burn patches are highly desirable habitats,” Ramirez explained, and understanding what has happened to them is made a high-priority.
Scientist Janice Coen, of the National Center for Atmospheric Research, now even hopes to use the detailed maps of the King fire to better understand of how these megafires – which burn hotter and are more difficult to contain than your standard wildfire – come to be.
“If you’re using the standard tools, you can’t explain the rapid fire growth,” she said. “The evolution of this fire seems to depend very much on winds the fire itself generated as it burned, and those winds in turn depend on the characteristics of the vegetation the fire had for fuel.”
“It’s a good case study,” Coen added, “because the new data sets can distinguish between vegetation characteristics that other data sets don’t distinguish.”
And who knows, maybe with the help of tools like MASTER and AVARIS, foresters will one day be able to act proactively – letting natural fires burn, but likewise ensuring that they don’t get out of hand and threaten delicate habitats or people. It’s a dream that Smokey the Bear would approve of, at least.
(Left) AVIRIS spectral map of the Rim fire. Charred wood appears red; green foliage is blue. There are no solid blue spots because no large areas remained unburned, but in purple areas, some plants are still alive. Photo : NASA/JPL-Caltech
The west side of the Rubicon River before and after the the King fire. Phot: USFS