Topic: Bushfires (wild fires) NSW 20th November 2006

[Jimmy Deguara]

Hi,

Given the lack of storms and the seriousness of the fire emergency, perhaps you can discuss the current bushfires affectign the blue mountains and the region around Putty. It seems to never end - we are told that areas have been burned out but now the fuel has regrown. The hot extremely dry conditions will continue to make it ideal for dangerous fires. At least you can say this time the fires were not deliberately lit. Lightning from the most recent storms that affected central through to northern NSW 13th November seemed to have been the culprit.

My question is, I know it can be difficult at times but how were the initial much smaller fires not contained by water bombing? I think the future with higher resolution remote sensing via satellites may assist in this process.

Regards,

Jimmy Deguara

[David C]

My question is, I know it can be difficult at times but how were the initial much smaller fires not contained by water bombing? I think the future with higher resolution remote sensing via satellites may assist in this process.

Regards,

Jimmy Deguara

I was thinking this myself last night in between taking breaths of bushfore smoke with isolated pockets of oxygen and nitrogen while lying in bed. I know nothing about the tools of the trade, but what sort of surveillance does the RFS do after dry electrical storms? Surely it is not hard in this day and age to combine information on lightning activity over fire risk areas. Surely they are in a position now to go over these regions with a fine tooth comb to identify spot fires from lightning strikes as quickly as possible - doesn't seem as though it would be rocket science to me.  Any RFS people here who know how these things work?

....or are the big out of control fires justifying the need for further funding.

[David C]

Smoke now into the blue on Sydney radar   

[Jimmy Deguara]

The fire plume indicated a major blaze this afternoon. It was hot with NW winds and obviously some elevated convection around - perhaps to lead to more bushfires.

Regards,

Jimmy Deguara

[nmoir]

HI guys , i ve spent the last few days covering the fires in the blue mts , yesterday at 12 midday , BOOOOOOOM!  the grose valley fire erupted like a volcano , the only comparable fire explosion like that ive seen was canberra. it moved 5km as a front in about 30 mins , i was near mt tomah.

the rfs use aircaft with heat sensing tech to keep an eye on fires  but the task of knocking even spotfires or lightning strike fires is beyond any helicopter , i have seen a fire crew spend over an hour and two entire tank fulls of water trying to put out one tree burning from the inside , choppers dont black out fires only cool them down and i can things getting political if they assigned an aircrane to every storm that moves through the state of course with the pathetic storm season weve had so far maybe that is possible

any way here is a couple of pix from yesterday note the chopper in the lower frame of the pyrocumulous

nick

[nmoir]

and here is one more

[nmoir]

and this is a pic of it ripping up the grose valley 3 days ago

[nmoir]

also these images are copyright Nick Moir / The Sydney Morning Herald (c)2006 and are for viewing only on this forum

sorry to be a nerd just incase someone decides to steal them and post them on another web site

nick

[Michael Bath]

Thanks for those pics Nick - spectacular !   

MB

[Jeff Brislane]

Nick, you've had more ground experience than anyone around fires so correct me if i'm wrong but really the RFS doesn't try and extinguise most fires like these because they just can't can they. Even in the early stages i would think that the odds of extinguising a fire with such dry fuel would be next to impossible. They're main job would be the preservation of life and property while the fire runs it's course. Windshifts imo would be the greatest weapon against fires and not water.

[Jimmy Deguara]

Ok we'll keep politics and decision making out of it.

The fires look very hot from your pics Nick - a concern to anyone in its path. I am assuming you were on the western side of the fires on Bells Line of Road? The pyrocumulus on the Canberra bushfires were massive! The helicopters look like toys next to the fires!

Regards,

Jimmy Deguara

[nmoir]

Canberra was like 10 of these at once , a gargantuan anavoidable front , what surprised me yesterday was the speed that it went from small white plumes of fairly boring smoke to broiling mass of fire  and ash in 10 mins , the winds had been strong and steady from west nth west for a few hours so i guess the fire just got a good uphill run and heavy fuel loads.

 the rfs are saying monday could be bad but central tablelands forcast is for easterly winds so i am not impressed but thursday has 40c temps in penrith so perhaps nth westrly winds moving through in a bit of strength then .

 has anyone used the haines index much and could explain how and what it shows? , i have been comparing it to bad fire days to see if it much use

[Jimmy Deguara]

Hi Nick,

This link seems to break it up well:

http://www.fs.fed.us/r2/fio/moreinfo/haines.htm

I guess an index is simply that - just a index of scores that help simplify for others the potential of something to happen. It surprised me about the link to instability though I must admit yesterday was reasonably unstable. Does this mean it aids in smoke to rise more freely in thermals and remove the mass of particles that could 'choke' fires to a certain extent?

Regards,

Jimmy Deguara

[nmoir]

I was wondering that , perhaps by being able to pull plumes up and away from the fire it helps create a concentrated low pressure area , and so increases the localised winds into the fire?

[nmoir]

just read the link and so this will be a helpful index , but jimmy how high would 850mb be in the atmosphere? 2km-3km?