Tasmania’s soil and fuel dryness for mid-2019 is more severe than mid-2018, which went on to produce one of Tasmania’s worst fire seasons.
Take a look at the maps above, borrowed from the www.Fire.Tas.gov.au and BOM websites today.
The June 2018 figures, in tabbed format, are below.
Those are impressive dry soil and fuel figures above, mainly on the east coast and midlands, but extending south to Hobart.
Prolonged, heavy rain could fix it. Let’s hope so.
I am no fire expert, but it seems clear that without rain, much of Tassie will be a tinderbox for the 2019/20 summer.
Keep in mind that the previous summer, with vast bushfires across Tasmania, lit by dry lightning, was not a new normal, but just another year in the planet’s upshift to a new, more extreme climate.
As I write this the northern hemisphere (now in summer) is alight.
Global ice is hitting record lows, some of it disappearing faster than forecast.
With Tasmania’s fire history, there’s never been a better time to remove pine trees, eucalypts and other flammable vegetation from around homes.
Where there is enough water to do so, replant with less dangerous trees.
Fire pumps and even bunkers should be considered. Have a fire escape plan.
Check out www.Fire.Tas.gov.au and other fire websites to get the good oil straight from the experts.
Key to the numbers from BOM
Drought Factor (DF)
The impact of KBDI, and any periods of recent rainfall that might dampen fine forest fuels such as ground litter, is incorporated into the fire danger index through another variable known as the Drought Factor (DF). The DF reflects the degree of availability of these fine forest fuels for combustion. It ranges from 0 to 10 with 10 representing the highest value of short-term rainfall deficiency and highest availability of fine fuels. The DF is calculated daily, once 24 hour rainfalls are available. Due to assumed interception by forest canopies, rainfall amounts of 3 mm or less are reset to zero in updating the DF.
Mount Soil Dryness Index (MSDI)
The MSDI is a measure of the longer-term dryness. The MSDI changes according to the evapo-transpiration and effective rainfall each day. It is a number between 0 and 200 mm, which roughly represents the amount of rain (in mm) needed to saturate the top layer of soil. SDI Primary uses one canopy class, and SDI Secondary has the option to use a different second canopy class.