Wireless weather monitoring predicts California wildfires

California wildfires can be devastating to local communities — damaging property and threatening safety. Residents of areas frequented by these violent and deadly infernos know that a rise in temperature, drop in humidity, and arrival of destructive Santa Ana winds signal that a forest fire is likely.

Recognizing that weather is the driving force behind most wildfires, researchers and first responders in San Diego utilize a sophisticated network of weather monitoring stations to detect potential wildfire conditions.

The High Performance Wireless Research and Education Network, a National Science Foundation-funded project, provides the communication backbone for these weather stations. Researchers at the University of California, San Diego, led by Hans-Werner Braun, are developing it. Braun is a research scientist at UCSD’s San Diego Supercomputer Center and principal investigator of the HPWREN.

The non-commercial, wide-area wireless network connects university campuses as well as a number of difficult-to-reach areas in remote environments. It is formed using Internet routers on mountaintops, interconnected via wireless links. In addition to first responder activities, it is used for collaborative cyber infrastructure on research and education — aiding projects such as monitoring supernovas in distant solar systems and studying wolf behavior in the desert.

“The collection of real-time data is one of the most valued aspects of scientific research, and that is what this network delivers,” Braun said. “Such data allows for increased knowledge and understanding of an array of scientific concepts, from heavily impacted ecological systems on Earth to the tracking of transient astronomical events in the universe.”

Using the high-speed HPWREN, weather data from remote locations can also be gathered and calculated in real time, providing near instant detection of Santa Ana conditions. Fondriest Environmental has supplied Vaisala WXT520 multi-parameter weather sensors to collect real-time data at several monitoring sites. These solid-state sensors were initially chosen several years ago to replace cup and vane anemometers, which had suffered mechanical failures.

The WXT520 was selected because it is a comprehensive and compact weather measurement device with direct digital output. It measures six essential weather parameters, including wind speed and direction, liquid precipitation, barometric pressure, air temperature, and relative humidity.

The WXT520s are part of a larger system that measures additional parameters. Sensor data is continuously processed to monitor for Santa Ana environmental conditions.

If fuel moisture drops below 7 percent, or if the relative humidity drops below 25 percent, and the wind direction is between 10 and 110 degrees at a speed above 25 miles per hour, automated real-time alerts are sent to public safety personnel via pager messages and email. Mobilization of firefighting resources — from aircraft to fire crews — can then begin in response to the fire risk.

The HPWREN benefits first responder activities in other aspects, too. It is a vital wireless connection for various Incident Command Posts and other firefighting centers, facilitating rapid coordination. Monitoring stations are also equipped with video cameras that provide live feeds, helping first responders spot and track wildfires once they’ve ignited.

Weather and video data from these stations are used significantly by local agencies, and it’s forwarded to the National Oceanic and Atmospheric Administration and National Weather Service. To learn more about the HPWREN, visit hpwren.ucsd.edu.