How bushfires generate their own weather
Why Victoria’s bushfires generated their own lightning, The Age , By Liam Mannix, March 4, 2019 — There are few sights more terrifying for a firefighter: a vast, dark storm cloud brewing above a bushfire, shooting out lightning.
On Sunday, the Licola bushfire east of Melbourne burned with such intensity it generated a huge thundercloud that fired hundreds of lightning strikes at nearby forests.
The Bunyip fire, which is believed to have wiped at least one town off the map, also generated its own weather system which fed the fire with extreme winds.
“It’s absolutely terrifying. And it’s dangerous as well, because that lightning can start new fires before the main fire,” says Dean Narramore, a meteorologist at the Bureau of Meteorology’s extreme weather desk.
How bushfires generate their own weather
As a bushfire burns, it generates hot, smoke-filled air.
This air is hotter than surrounding air and rapidly rises, forming a smoke plume.
As the plume rises, atmospheric pressure falls. This causes the plume to spread out, generating a “mushroom” on top of the plume.
The smoke plume is filled with moisture which is released by burning trees. The higher you go in the atmosphere, the cooler it gets, so the top parts of the plume get chilled.
This causes the moisture in the plume to condense (turn from water vapour into tiny water droplets) and form a cloud.
As the plume rises rapidly into the sky, cool air is sucked in to replace it. This causes extreme winds near the firefront. To fight a fire, you need to know which way it is burning. But when a fire-cloud forms and starts generating strong and unpredictable winds, the fire can become chaotic.
“All this air rushes into the fire. You can imagine air coming from all different angles, feeding in – and oxygen is a very important part of fire. It causes fires to race up and down hills,” Mr Narramore says…….. https://www.theage.com.au/national/victoria/why-victoria-s-bushfires-generated-their-own-lightning-20190304-p511kd.html
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1.This month.
The Road to War brings a sharp focus to why it is not in Australia’s best interest to be dragged into a war with China which will almost inevitably go nuclear very quickly. The filmmaker has interviewed some of Australia’s senior foreign policy analysts who have vast experience behind them in analysing what really is going on here as the United States rattles its sabres with China. And sets us up to be its proxy, like the poor Ukranians have been fed into the Meatgrinder. So America can remain the Top Dog. The Road to War reveals how the United States through its spy base at Pine Gap and by stationing six nuclear capable B52 bombers in the Top End (without permission from the traditional owners) is making Australia a prime nuclear target if the current war of words suddenly melts down into full scale war.
The Road to War shows the implicit connection between Carbon emissions (the US military uses a whopping 70% of America’s annual petroleum to move its armies and vast War Machine around the globe to its 800+ military bases..but under a loophole wangled at Kyoto, the US military does not have to report its C02 annual emissions). The Road to War starts screening at selected cities and regional centres in March. See the trailer end for details.
Antinuclear 
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