What is a pyrocumulus? What has formed in Ponent is on a scale never seen before in Catalonia.

This Tuesday afternoon, while the fires of Poniente, which have already caused two deaths, burned vigorously, A huge column of smoke and ash was generated that could be seen from the entire plain of Lleida. pyrocumulus, and this one in particular reached a height of between 14,000 and 19,000 meters, according to the Fire Brigade and the Meteorological Service of Catalonia. A phenomenon of a magnitude never before observed in Catalonia.

But what exactly is a pyrocumulus cloud, and how does it form? It's a cloud of enormous dimensions that is generated naturally due to the combination of fire and the humidity of forest vegetation. The flames cause extremely high temperatures, which quickly evaporate all the water in the burning vegetation, especially the trees. This causes a rapid rise of water vapor, which collides with colder air at high altitudes and, upon condensing, forms this pyrocumulus cloud. It is a cloud of smoke and ash that generates its own meteorology, with strong gusts of wind and erratic changes in wind direction. Therefore, it is very dangerous and a major challenge for firefighting efforts.

This is a common phenomenon in large forest fires, but what's not so common is for a cloud of this nature to reach such a high altitude as the one seen Tuesday night. Pyrocumulus clouds have only been analyzed in Catalonia for relatively few years, but since records began, one so high and so violent has never been seen, as it caused wind gusts of up to 125 km/h.

Sixth generation fires

This extraordinary event could be explained by the extreme weather conditions of recent days. We are in the midst of a heat wave after an exceptionally dry and warm June. These factors have very likely caused the flames to spread much more rapidly than usual. In fact, it is one of the fastest-spreading fires in all of Europe recently. Therefore, while awaiting the study and final conclusions, it is possible that so much burned vegetation and steam released in a short period of time may have contributed to the growth of this exceptional pyrocumulus cloud. These extreme conditions are typical of what is known as a sixth-generation fire, characterized by rapid spread due to being highly unpredictable and with great devastating potential. These megafires, or sixth-generation fires, are caused primarily by the advance of climate change and poor landscape management.