Author Topic: Soil Dryness Index  (Read 7804 times)

Offline bajdas

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Soil Dryness Index
« on: January 31, 2007, 04:50:12 PM »
On the 17th December I attended some training with CFS staff. It was stated then that the 'Soil Dryness Index' at Mt Crawford was very, very high.

Can this measure be viewed on a website ? Is this only done at Mt Crawford or is the testing completed at other sites.

I am curious on how much of the recent rain, changed the index value.

Thanks,
Andrew Mac.
Andrew Macmichael
lives at Pt Noarlunga South.

My personal opinion only.

Offline medevac

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Re: Soil Dryness Index
« Reply #1 on: January 31, 2007, 04:59:49 PM »
Its conducted at various sites throughout the state.... i dont believe it is available on the internet to the public though..... ?

Offline 24P

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Re: Soil Dryness Index
« Reply #2 on: January 31, 2007, 05:07:48 PM »
Soil Dryness at selected lacoations as at 0900 today
L/H number is the drought factor                   
Mount Crawford 135 9
Mount Barker 164 10
Kuitpo 142 9
Parawa 71 6
 
Naracoorte 141 8
Coonawarra 124 7
Mount Gambier 144 9
 
Cape Borda 166 10
Kingscote Airport 172 10
 
Wudinna 175 10
Cleve 166 10
Port Lincoln Airport 167 10
 
Maitland 162 10
Clare 120 8
 
Renmark 176 9
Lameroo 150 9
Keith 148 9
Meningie 149 9
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Offline 24P

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Re: Soil Dryness Index
« Reply #3 on: January 31, 2007, 05:09:20 PM »
Sorry forgot to add these are from the BOM website.
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Offline medevac

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Re: Soil Dryness Index
« Reply #4 on: January 31, 2007, 05:15:29 PM »
which link through the bom 24p?

Offline 24P

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Re: Soil Dryness Index
« Reply #5 on: January 31, 2007, 05:26:59 PM »
Are you able to log on to the registered users site?
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Offline bajdas

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Re: Soil Dryness Index
« Reply #6 on: January 31, 2007, 06:27:31 PM »
Soil Dryness at selected lacoations as at 0900 today
L/H number is the drought factor                   
Mount Crawford 135 9
Mount Barker 164 10
Kuitpo 142 9
Parawa 71 6
 
Naracoorte 141 8
Coonawarra 124 7
Mount Gambier 144 9
 
Cape Borda 166 10
Kingscote Airport 172 10
 
Wudinna 175 10
Cleve 166 10
Port Lincoln Airport 167 10
 
Maitland 162 10
Clare 120 8
 
Renmark 176 9
Lameroo 150 9
Keith 148 9
Meningie 149 9


What do the numbers mean ? Esp the 'drought factor'

I understood the SDI was the amount of millilitres of water required to saturate the soil. Is this correct ?

Thanks in advance for the information.
Andrew Macmichael
lives at Pt Noarlunga South.

My personal opinion only.

Offline Chirp / Vibrate

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Re: Soil Dryness Index
« Reply #7 on: February 01, 2007, 06:04:35 AM »
The Mount Soil Dryness Index (SDI) is calculated using the 24 hour rainfall and maximum temperature to 9 am each day and is an indicator of the amount of rainfall (in mm) required to saturate the top layer of soil within a forested area.

The Mount SDI value varies, depending on what type of forest canopy is assumed. For locations in the Mount Lofty Ranges and Lower South East districts, the Mount SDI is representative of a pine plantation (indicated by the darker green shading in the table above). For the remaining locations (olive green shading), the calculated Mount SDI is representative of an open eucalypt forest.

For full details, see the paper by A. B. Mount, "The derivation and testing of a soil dryness index using run-off data", published as Bulletin Number 4 by the Forestry and Timber Bureau, Canberra, August 1967.

The Drought Factor (DF) calculation is based on the rainfall record over the past 20 days and the current Mount SDI.

For full details, see the paper by D. Griffiths, "Improved Formula for the Drought Factor in McArthur's Forest Fire Danger Meter" published in the Australian Foresty Journal, Vol 62, No 2, pp 202-206 (1999).

Drought Factor.
This is a broad measure of fuel avalilability as determined by drought index and recent rainfall. Where the effect of one reain peios is superimosed on another, use the lowest drought factor.

You did ask...

Offline bajdas

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Re: Soil Dryness Index
« Reply #8 on: February 01, 2007, 12:24:44 PM »
You did ask...

Yep & thanks.......I think.....will let you know in a month when I absorb this.....hee hee  :wink:
Andrew Macmichael
lives at Pt Noarlunga South.

My personal opinion only.

Offline lilmiss_firey

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Re: Soil Dryness Index
« Reply #9 on: February 01, 2007, 11:30:11 PM »
The Mount Soil Dryness Index (SDI) is calculated using the 24 hour rainfall and maximum temperature to 9 am each day and is an indicator of the amount of rainfall (in mm) required to saturate the top layer of soil within a forested area.

The Mount SDI value varies, depending on what type of forest canopy is assumed. For locations in the Mount Lofty Ranges and Lower South East districts, the Mount SDI is representative of a pine plantation (indicated by the darker green shading in the table above). For the remaining locations (olive green shading), the calculated Mount SDI is representative of an open eucalypt forest.

For full details, see the paper by A. B. Mount, "The derivation and testing of a soil dryness index using run-off data", published as Bulletin Number 4 by the Forestry and Timber Bureau, Canberra, August 1967.

The Drought Factor (DF) calculation is based on the rainfall record over the past 20 days and the current Mount SDI.

For full details, see the paper by D. Griffiths, "Improved Formula for the Drought Factor in McArthur's Forest Fire Danger Meter" published in the Australian Foresty Journal, Vol 62, No 2, pp 202-206 (1999).

Drought Factor.
This is a broad measure of fuel avalilability as determined by drought index and recent rainfall. Where the effect of one reain peios is superimosed on another, use the lowest drought factor.

You did ask...



so with that... the higher the number, the drier the soil is???

 

anything