Urban fires have plagued Japan for generations, the most notorious of which killed nearly 45,000 people.
A strong earthquake and tsunami claimed thousands of lives around Tokyo and Yokohama in 1923, but then came the fire. The region’s wooden homes, cookstoves, and ruptured gas lines ignited fires that extreme winds worsened, soon setting the entire city ablaze. Most people were immolated by a 300-foot-tall funnel of fire known as a “dragon twist,” according to Smithsonian Magazine.
Japan’s tragedies drove the nation to become a leader in urban fire and combustion research, an expertise it still fosters today. It’s now sharing that knowledge with researchers from South Africa and Botswana.
The “dragon twist” representation above may be one of the oldest artistic representations of the firebrand showers. The phenomenon happens when large amounts of embers from a fire get blown airborne, igniting possible fires elsewhere.
The 1923 tragedy and others like it pushed Japan to study the phenomenon, leading to the nation building the world’s first large-scale wind tunnel for fire testing, nicknamed the “Dragon”. The research replicates building and vegetation ignitions during firebrand showers, according to Samuel Manzello, a combustion researcher at Tohoku University’s Institute of Fluid Science.
“Our firebrand research using the Dragon had become very well-known across the world,” Manzello told Wildfire Today. “In Japan, you could conduct experiments on actual, real-scale building components. In the USA, there were no such facilities to do this type of research.”
Tohoku University‘s firebrand research would go on to catch the attention of researchers in Southern Africa, who have dealt with numerous firebrand shower disasters. The joint interest led to the Japan Science and Technology Agency launching the AfriWUIFire project in 2023 to bring together experts from both regions to help mitigate firebrands’ global threat.
The joint research would also help establish international testing methods and common testing methodology, Manzello said. The vast difference in vegetation types in both regions benefit researchers in determining the propensity of each vegetation type to produce firebrands, which can then be used in numerous countries.
“Through years of research in Japan, we have developed experimental methodologies to better understand and quantify the dangers of firebrands, so exchange of information is important,” Manzello said. “At the same time, there is a need to develop globally accepted international standard test methods for firebrand quantification from vegetative and structural fuel combustion. The project affords the ability to independently compare test methods across multiple countries for disparate vegetation types, to develop such international test methods.”
AfriWUIFire researchers from Japan, including Manzello, traveled to South Africa in April to evaluate local fire hazards and then attended an Africa-Japan Collaborative Research workshop in Botswana. Soon, AfriWUIFire researchers from Africa will visit Japan, in part to conduct full-scale vegetation combustion experiments and quantify firebrands using the Dragon.
Click here to read more about the partnership.
Firebrands are the number one cause of structure ignition accounting for 80-90% of structure loss according to IBHS. They too have the same facility in South Carolina to model structure ignition from embers. Too bad OSU didn’t get the memo about what causes structure loss when they created to hazard map.