New Research Suggests Drones Could Be the Best Tool for Understanding How Wildfires Behave
BY Zacc Dukowitz12 November 2020
Wildfires have been ravaging the west coast this year, with smoke from the fires blowing across the entire country, reaching all the way to the east coast.
Drones have been helping with efforts to fight these fires, primarily by providing aerial visual and thermal data on their progress.
But a research project out of San Jose State University’s Fire Weather Research Laboratory has been researching a different way that drones can help contain wildfires.
Using UAVs, researchers have been studying wildfire meteorology to see if a drone might be the best tool for understanding atmospheric conditions during an active fire.
Wildfires Are Erratic, Which Makes Them Hard to Fight
Wildfires move erratically, which can make them very hard to fight.
If, for example, wind is blowing at the surface of the ground in one direction while wind is moving above that layer in another direction, the direction the fire takes could change suddenly, in ways that are hard for those working on the ground to predict.
One thing we know about fire behavior—and most people neglect this—is that the vertical profile in the wind has been shown to cause erratic fire behavior.
– Craig Clements, Professor in the Fire Weather Research Laboratory
Researchers have been working to find better tools to study the ways the atmosphere can impact a developing fire, and it looks like drones may be an ideal fit.
[Related reading: Drone Incursions Over Wildfires on Decline, Sign that Education Is Working]
How Drones Can Provide Real-Time Meteorological Information about Active Fires
Traditional fire research relies on using towers and balloons to capture vertical wind profiles.
In the case of the tower, it will be outfitted with a sensor like a sonic anemometer to collect meteorological data. And in the case of the balloon, it will be equipped with a radiosonde to collect similar data, which is a small, light-weight instrument designed to take atmospheric measurements and transmit them by radio.
While these approaches can produce useful data for researchers, they are not practical tools for understanding the movements of a wildfire in real-time. You can’t suddenly erect a tower near a wildfire, and putting a balloon in the air near an active fire zone is also not a realistic option.
But you can put a drone in the air and, in almost no time at all, start collecting useful data to help you understand how an active fire might behave.
Using a UAV, researchers at San Jose State University have been collaborating with the U.S. Forest Service (USFS) and the Desert Research Institute (DRI) to take the vertical profiles of atmospheric variables during active fires.
To create these meteorological profiles of wildfires, the team at the Fire Weather Research Laboratory uses a DJI Matrice 200, which they chose primarily for its obstacle avoidance features and its ease of maintenance.
Photo credit: Fire Weather Research Laboratory
The M200 was equipped with a special sensor to help researchers sample the 3-dimensional vertical wind profiles from winds generated by wildfires.
The sensor is called a TriSonica Mini Wind and Weather Sensor, and it’s made by Anemoment LLC. Researchers mounted the sensor on a carbon fiber pole that extended off the body of the M200, and they attached the sensor’s data logger to the top of the drone (see image below).
Photo credit: Fire Weather Research Laboratory
Prior to testing the sensor in the field, the team conducted several tests to determine the ideal location for the sensor relative to the drone.
They also tested the accuracy of the sensor while in flight, comparing data captured by the sensor attached to the M200 with a separate sonic anemometer attached to a nearby tower. These tests help them determine that the sensor on the drone was able to perform as well, if not better, than the sensor on the tower.
Initial Findings from the Fire Weather Research Laboratory’s Drone Experiments
So far, the research team has studied controlled and test burns as well as data captured in experimental fire settings.
The goal of these efforts is to build a reliable dataset for understanding fire behavior, which include aspects of how wildfires behave, such as the rate of fire spread and smoke transport.
Their research demonstrates that drones can be used to collect meteorological data during controlled wildland fires, as well as potentially during large wildland fires.
The UAS enables us to see the evolution of the wind field really close to the fire front. This is something you can’t normally get without completely destroying a bunch of instruments.
– Matthew Brewer, Graduate Research Assistant in the Fire Weather Research Laboratory
Even further, initial findings from their research indicate that a drone may be able to provide an even more nuanced view of meteorological conditions during an active fire than the tools traditionally used, revealing small scale temperatures and wind structures that could be missed by radiosondes due to their fast rate of ascent.
As this technology develops, future wildfire operations could have two sets of drone teams working alongside each other—one to collect aerial and thermal data, and one to collect atmospheric data.
What do you think—will drones become a regular tool for understanding wildfire meteorology during active wildfire operations? Share your thoughts in this thread on the UAV Coach community forum.