Note the large burnt stump visible at left in the photograph.
My objective was to illustrate that there was nothing difficult about the terrain in the general area of the lightning strike that would have prevented physically fit, experienced and safety conscious DELWP firefighters and also that the vegetation was not too dense to prevent effective use of suitable and properly tasked water bombing aircraft.
I've been seeking advice on lightning strikes and what to look for to be as sure of my facts as possible and provide the following examples, and there are many more, of what I've studied:
"Science Made Simple" that includes an informative video of the details of a lightning strike.
"National Geographic on Lightning" with another informative video.
Concerning the Jamieson Creek lightning strike, I find the following in the National Geographic discourse describes the situation found that I alluded to with my reference to the "large burnt stump":
Lightning's extreme heat will vaporize the water inside a tree, creating steam that may blow the tree apart.
This is the remains of the tree that I believe took the brunt of the lightning strike.
The burnt stump shown at left in the first photograph in this posting is at left in Plate 1. The fallen tree in the centre has separated from the stump. The damaged stump in the centre appears to have been damaged by the fallen tree to its left.
Note the severe burn isolated to the lower part of the tree. This deep, small area of burning is consistent with the intense heat from a lightning strike at or near the base of the erect living tree—lightning does not necessarily strike the top of a tree, it all depends on where the upwards moving positive charge “streamer” emanates from, and it could even be the ground alongside a tree or an isolated rocky outcrop.
Plate 2 is another view of the stump and its fallen top as indicated.
Plates 3 and 4 show the stump. Note the depth of the charring, particularly concentrated at the left side of the stump.
Plate 3 also shows the damage caused by a violent separation of the tree from the stump, almost as if the result an explosion.
Back to the tree; it was a living gum—EVC 201:Shrubby Wet Forest from Biodiversity Interactive Map - 3.2 indicates Mountain Grey Gum Eucalyptus cypellocarpa and checking Leon Costerman’s Native Trees and Shrubs of South-Eastern Australia satisfies me—containing moisture that would have required far more and prolonged exposure to heat of a level that's not associated with a fire moving across the ground to produce a burn of this depth.
I suspect it was a relatively mild fire for those first couple of day, as logs and larger stumps already on the ground in the area had suffered little more than superficial charring, as Plates 5, 6, 7 and 8 show.
An explanation for the seemingly burnt trees. Scattered within the area are Messmate Stringybark Eucalyptus obliqua that account for a few trees with blackened trunks, which is due to the fibrous bark but not the trunks burning. Plate 9 is an example of Messmate Stringybark from the Christmas Hills area.
Costerman describes the bark of the Mountain Grey Gum as:
Smooth, grey often with yellow and whitish patches, sheds [bark] in strips or plates; may be rough and darker at base.
Plate 10 shows the relatively easily ignitable roughness at the base of a Mountain Grey Gum (or very similar) and becoming plates or strips further up the trunk. Sufficiently dry and standing off from the trunk can see fire extend further up the trunk to involve this bark without igniting the trunk. The arrows indicate examples of the stages of bark from the ground up.
Plates 11 and 12 show the unburnt vegetation to the west and on the opposite side of the control line from the fire area, photographed at similar level to the lightning strike.
Plate 12 shows bark renewing itself on Stringybarks following much earlier exposure to fire.
Photos in this and recent postings show that there was nothing difficult about the area for fit and experienced DELWP firefighters to round up the initially small fire in the first couple of days, and to argue that the vegetation was to dense to respond to proper air attack is arrant nonsense if DELWP's use of water bombing aircraft in Gippsland in recent days is any guide.
The annotated Google Earth photo shows the way to where I believe the lightning struck: Position 11. Not difficult to find nor hard to reach on the ground, but always with an eye upwards at the trees above. And approximately 250 metres from a well-formed four wheel drive track.
Why then the failure to slay the Jamieson Creek beast in its infancy?
On page 27, third paragraph under the heading "Initial fire control strategy 19–21 December", in the "IGEM's Review of the initial response ..."
Through the period 19 to late 21 December, the IC's [Incident Controller] broad strategy was to establish bare earth containment lines to limit the fire's spread within the area bounded by the Cumberland Track to the north, and Jamieson Track to the south.
As can be seen in the following annotated Google Earth photo, the area of land between Cumberland Track and Jamieson Track is huge compared to the size of the fire on 19 December.
Why this plan so early and probably before the Incident Control Team really knew what they had to contend with?
Inexperience, incompetence, panic, interference from above, budget restraint or was the Incident Controller 'marching to the beat of a different drummer' — sign found at the corner of Curtis Track and Cumberland Track on 9 January 2017?
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