Deadly wildfires are raging around the globe again this year, driven by heat waves and dry conditions exacerbated by global warming. Major fires in Australia, Europe, North America and Russia have prompted states of emergency and calls for assistance from the international community, and the conditions in Sweden have resulted in wildfires occurring north of the Arctic Circle.
Adding to the list of animals that make use of tools, it turns out that Australian raptors deliberately set fires to flush out prey, picking up burning sticks from an existing fire and dropping them onto dry grass to start a new conflagration. Although this is news to modern science, stories of this behavior are interwoven into Aboriginal culture, from knowledge that spans back through the millennia.
The fires currently searing through the Australian bush between Lithgow and Bilpin could create an unusual cloud formation known as a ‘Fire Cloud’ or pyrocumulus, predict fire analysts. The unique weather phenomenon only forms when areas of intense heat, such as bush fires or volcanoes, meet with an unstable atmosphere.
As fires burn, the hot air generated rises in a huge column upwards, with the space underneath being filled by cooler air, a process producing a convection column. The hot-air columns created can be extremely large and can rise high into the atmosphere carrying a large amounts of water vapour – one of the main combustion products of fire.