It has a difficult name to pronounce, it is rare, but it may have been registered twice this year in Portugal
The deadly fires of Pedrógão Grande, on June 17, and the central zone, on October 15, may be related to a rare phenomenon, with a difficult name to pronounce: pyro-cumulonimbus. Two members of the Independent Technical Commission that investigated the fires of early summer that killed 64 people believe that this is what happened, they told TSF.
“Pyro-cumulonimbus is a storm created by a fire,” says Paulo Fernandes, Ph.D. in Forestry and Environmental Sciences at the University of Trás-os-Montes and Alto Douro (UTAD). Among the images he saw and the reports he heard about the fires, highlights the cloud of the fire, which describes as “very developed, very high that at a certain point began to produce lightning and thunder.” “This is one of the signs of pyro-cumulonimbus,” he concludes.
This phenomenon had already been described by the Independent Technical Commission regarding the fire of Pedrógão. “It is a cloud of smoke that rises very high, 10 kilometres.
When this cloud rises so high, in addition to condensation, ice is formed and is the friction between the ice crystals that can cause lightning, caused by the fires themselves, and that sometimes give rise to new ignitions, “describes Paulo Fernandes, for whom the existence of a pyro-cumulonimbus” would explain, at least in part, the devastation that was observed in these two great fires of the interior. “According to what the researcher told TSF, “a typical forest fire does not cause that destruction,” and it is necessary for that to happen “strong wind, with projections at a great distance from incandescent materials.”