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Re: Australia is on fire

Posted: Fri Jan 24, 2020 3:36 pm
by plodder
lpm wrote:
Fri Jan 24, 2020 2:12 pm
?
Australia is in the bottom left. The UK is an insignificant and rather pathetic island near the top. The dust from the Sahara can go south to the Amazon or north and swirl round to Europe. But the Amazon fires don't go to the northern hemisphere.
The swirly thing appears to go on a carribean holiday, and then back home to the UK on a thing called “the jet stream” or the “gulf stream” or something

Re: Australia is on fire

Posted: Fri Jan 24, 2020 11:31 pm
by Chris Preston
bjn wrote:
Fri Jan 24, 2020 3:18 pm
My google-fu is weak. But I swear I heard on a recent ABC* Science Show that there has been a significant uptick in heat related deaths in Australia. Can't find the reference nor remember the exact episode.

*Australian Broadcasting Corporation
There has not been an estimate of the number of deaths from the December heatwaves released. There were 266 people admitted to hospital for heat-related illnesses in Adelaide alone during the heatwave.

The 2009 January/February heatwaves caused 432 extra deaths.

Re: Australia is on fire

Posted: Fri Jan 24, 2020 11:42 pm
by plodder
I think I remember reading that heatwaves in France a few years ago directly led to something like 15,000 fatalities.

Re: Australia is on fire

Posted: Fri Jan 24, 2020 11:48 pm
by Chris Preston
plodder wrote:
Fri Jan 24, 2020 11:42 pm
I think I remember reading that heatwaves in France a few years ago directly led to something like 15,000 fatalities.
The 2003 heat wave. France has almost 3 times the population of Australia and is less well prepared to manage heat waves.

I think this is the thing to really worry about. Heat waves in Australia will get worse, but as Australia has always had heat waves people (mostly) understand not to do stupid stuff in the heat. Countries that don't see heat waves of the extent we do will have major problems the first time one turns up.

Re: Australia is on fire

Posted: Sat Jan 25, 2020 8:36 am
by plodder
Right - thanks Chris. So preparedness (don't do silly things) and tech (air con) and clued up incident response made a huge difference, maybe a factor of ten?

Re: Australia is on fire

Posted: Sun Jan 26, 2020 12:27 am
by Squeak
plodder wrote:
Sat Jan 25, 2020 8:36 am
Right - thanks Chris. So preparedness (don't do silly things) and tech (air con) and clued up incident response made a huge difference, maybe a factor of ten?
I don't know about the ratios but that sounds about right. Houses on the mainland of Australia tend to have some ability to shed heat. And public buildings are all air conditioned, so you can escape if necessary. And people have strategies. As my my little niece gets taught "practice makes better".

Additionally, there seems to be some seasonal migrations happening in some of the indigenous settlements in central Australia. Spend the milder months on country and head into bigger regional centres with airconditioning when the temperatures get unsafe.

Re: Australia is on fire

Posted: Thu Jan 30, 2020 11:20 pm
by Brightonian

Re: Australia is on fire

Posted: Fri Jan 31, 2020 8:38 am
by Gentleman Jim
Big changes coming to south and southeast Australia, according to BBC weather
Melbourne dropping from 43c to 17c over just a couple of days but with severe thunderstorms.
Meanwhile, Basementer - beware the severe gales and torrential rain

Re: Australia is on fire

Posted: Fri Jan 31, 2020 4:06 pm
by basementer
Gentleman Jim wrote:
Fri Jan 31, 2020 8:38 am
Big changes coming to south and southeast Australia, according to BBC weather
Melbourne dropping from 43c to 17c over just a couple of days but with severe thunderstorms.
Meanwhile, Basementer - beware the severe gales and torrential rain
Ta, but probably OK where I am, the worst of it's currently forecast to hit the other island.

Re: Australia is on fire

Posted: Sun Feb 09, 2020 9:50 pm
by bjn
The rains seem to be doing their job in NSW in putting out a whole range of fires, probably a bit too good.

bl..dy droughts and bl..dy flooding rains.

Re: Australia is on fire

Posted: Sun Feb 09, 2020 10:19 pm
by bjn

Re: Australia is on fire

Posted: Sun Feb 09, 2020 10:53 pm
by plodder
presumably intense fire alters soil structure, changing its ability to hold moisture and affecting run off rates etc. No idea how though, I can imagine increased cracking but also compaction.

Re: Australia is on fire

Posted: Sun Feb 09, 2020 11:47 pm
by bjn
plodder wrote:
Sun Feb 09, 2020 10:53 pm
presumably intense fire alters soil structure, changing its ability to hold moisture and affecting run off rates etc. No idea how though, I can imagine increased cracking but also compaction.
I’d also think the lack of leaves and undergrowth wouldn’t help with holding soils together nor reduce the impact of heavy rain on soils.

Re: Australia is on fire

Posted: Mon Feb 10, 2020 1:16 am
by Squeak
After the last lot of big trains in recently burned catchments, there mass fish deaths. For some reason, fish don't much like vast quantities of ash suddenly landing in their river. :/

I know almost nothing about the effect of fire on soil structure/water holding capacity so I won't converge further.

Re: Australia is on fire

Posted: Mon Feb 10, 2020 8:19 am
by plodder
I’ll speculate that it’s not just ash, but fine soil that runs into the rivers.

Re: Australia is on fire

Posted: Mon Feb 10, 2020 9:07 am
by bjn
CSIRO blog post on the effect of rain post bushfire. Rain isn’t absorbed as before, erosion increases, more organic run off, more silt and a whole bunch of poisons as well. Not good for the soils or the waterways.

Re: Australia is on fire

Posted: Mon Feb 10, 2020 11:59 am
by plodder
Cool thanks. This fits with the position that rare and extreme events are far more influential in shaping the physical world than gradual small processes. For example, rivers tend to change course after big floods or other erosive events rather than gradually moving. Note “tend” - lots of factors in play.

Re: Australia is on fire

Posted: Fri Feb 14, 2020 4:01 pm
by jaap
The NSW fires are now officially under control. Several are still burning, but they are all contained.

Re: Australia is on fire

Posted: Fri Feb 14, 2020 8:39 pm
by Beaker
plodder wrote:
Mon Feb 10, 2020 11:59 am
Cool thanks. This fits with the position that rare and extreme events are far more influential in shaping the physical world than gradual small processes. For example, rivers tend to change course after big floods or other erosive events rather than gradually moving. Note “tend” - lots of factors in play.
James Hutton may want to disagree there. I suspect most geologists would find space for both, unless they are of a particularly religious bent where most features are explained by the Biblical flood.

Chomolungma was gradually laid down on the sea bed, before being gradually thrust up to its current height, and is being gradually eroded by glaciers. On the other hand, the Old Man of Hoy, also laid down as sediment, and gradually eroded into an arch, will overnight have become a stack in some catastrophic storm.

I used to watch a particular channel change in Morecambe bay.* It could get dramatically shifted in a big storm, and drift back to broadly the same place very gradually thereafter. Hard to say one process was far more influential than the other.

*Lunchtime walk along the edge of the factory, not in a professional capacity. SO was fluvial geomorphologist however, so I know my pools from my riffles.

Re: Australia is on fire

Posted: Fri Feb 14, 2020 10:28 pm
by Herainestold
We are in a new geological era, where the old rules do not hold.

Because of human induced influences catstrophic changes can happen instantly with no warning.

Look at corona virus for instance.

Re: Australia is on fire

Posted: Fri Feb 14, 2020 10:49 pm
by plodder
Beaker wrote:
Fri Feb 14, 2020 8:39 pm
plodder wrote:
Mon Feb 10, 2020 11:59 am
Cool thanks. This fits with the position that rare and extreme events are far more influential in shaping the physical world than gradual small processes. For example, rivers tend to change course after big floods or other erosive events rather than gradually moving. Note “tend” - lots of factors in play.
James Hutton may want to disagree there. I suspect most geologists would find space for both, unless they are of a particularly religious bent where most features are explained by the Biblical flood.

Chomolungma was gradually laid down on the sea bed, before being gradually thrust up to its current height, and is being gradually eroded by glaciers. On the other hand, the Old Man of Hoy, also laid down as sediment, and gradually eroded into an arch, will overnight have become a stack in some catastrophic storm.

I used to watch a particular channel change in Morecambe bay.* It could get dramatically shifted in a big storm, and drift back to broadly the same place very gradually thereafter. Hard to say one process was far more influential than the other.

*Lunchtime walk along the edge of the factory, not in a professional capacity. SO was fluvial geomorphologist however, so I know my pools from my riffles.
Can’t quite remember the terminology, but this is something I remember from when I was taught fluvial geomorphology, something like the mean event something or other. Maybe your SO can remember!

Re: Australia is on fire

Posted: Sat Feb 15, 2020 12:16 am
by bjn
Herainestold wrote:
Fri Feb 14, 2020 10:28 pm
We are in a new geological era, where the old rules do not hold.

Because of human induced influences catstrophic changes can happen instantly with no warning.

Look at corona virus for instance.
Corona-virus ain't got nothing on the black death. That was one kick-ass motherf.cker of a disease.

Re: Australia is on fire

Posted: Sat Feb 15, 2020 12:29 am
by Gfamily
bjn wrote:
Sat Feb 15, 2020 12:16 am
Herainestold wrote:
Fri Feb 14, 2020 10:28 pm
We are in a new geological era, where the old rules do not hold.

Because of human induced influences catstrophic changes can happen instantly with no warning.

Look at corona virus for instance.
Corona-virus ain't got nothing on the black death. That was one kick-ass motherf.cker of a disease.
And likely did enormous good for those that constituted the next generation.

Re: Australia is on fire

Posted: Sat Feb 15, 2020 12:32 am
by bjn
Gfamily wrote:
Sat Feb 15, 2020 12:29 am
bjn wrote:
Sat Feb 15, 2020 12:16 am
Herainestold wrote:
Fri Feb 14, 2020 10:28 pm
We are in a new geological era, where the old rules do not hold.

Because of human induced influences catstrophic changes can happen instantly with no warning.

Look at corona virus for instance.
Corona-virus ain't got nothing on the black death. That was one kick-ass motherf.cker of a disease.
And likely did enormous good for those that constituted the next generation.
Yep, huge social change. A shortage of labour across Europe meant the lives of the surviving peasants and their descendants improved significantly. It ended the Middle Ages.

Re: Australia is on fire

Posted: Sat Feb 15, 2020 12:36 am
by Gfamily
Gfamily wrote:
Sat Feb 15, 2020 12:29 am
And likely did enormous good for those that constituted the next generation.
Though, it has to be said that the accessibility of raw resources of minerals etc, has been almost universally reduced in the last 50 years. So whichever of our next generations is the one that has to rebuild, it is likely to have a fuckawful job getting hold of them; though the empty city canyons may provide rich pickings.