|Fire Weather Forecasting in Australia Summer 2009|
|“Victorian Brush Fire"
February 7th, 2009
John Saltenberger, Meteorologist, USFWS
On Feb. 18, 2010, we had nine attend this technical meeting, hosted by the City of Hillsboro, Fire Station #3. Oregon-AMS President Bobby Corser gave some opening remarks.
An exchange program between the Australian Bureau of Meteorology (BOM), NOAA’s National Weather Service, and five Federal fire-management agencies has enabled forecasters from both countries to go on a detail of 2-4 weeks. John was sent to Melbourne, capital of the State of Victoria, in April 2008 and February 2009.
February 7th, or “Black Saturday”, was the most infamous, costliest, and deadliest fire event in Australia’s history. The terrain of Victoria is 80% desert and 20% forest – similar to central California – but the size of the continental U.S. Australia has less mountains than most continents. The Great Dividing Range, east of Melbourne, separates the sea air from interior land air. This is also an important major wine-grape growing area. Zonal air flow is faster, due to much less land and frictional resistance. Water resources are tightly managed.
John was sent to give BOM office forecast support. The Aussies use prescribed fire projects to lessen the fire risk. John was assigned to five fire projects.
The major fire fuel is the Eucalyptus (gum) tree – highly flammable and drought resistant – similar to Californian chaparral. Southern Australia has been in a drought for ten years with the driest-on-record (0% - 20% of normal, January 2009) for the last two years. Interior winds, dryness, and hot temperatures preceded the fire. For example, the daily mean for January 30th was 35.4 degC (90 degF) and January 27-31 was 15-18 degC above normal (Aussie summer).
On the day of the fire, Victoria hit an all-time record high of 48.8 degC (120 degF). Major fires erupted from noon to midnight, triggered by 115-120 degF high heat, increased wind, and very low (6% to 9%) relative humidity. A cold front helped to pump up very dry and strong 30-50 mph northwest winds. Thermal troughs develop very quickly, unlike the U.S. west coast. The fire trajectories were northeast. The passage of the front shifted the trajectory to southeast.
Damage included over 400 fires, 170 deaths (most in Kinglake and Marysville), over 2000 homes lost, and 7500 homeless. Over 90% home-owners “stayed and defended” their homes, as per tradition and policy, but that practiced failed this time, due to the severity of the event. Many died in their cars as they tried to escape the rapid fire wall. The MacArthur Fire Index was near 300 or “code red.” The previous record was 100, so this event was off the chart. The Australian Government is re-thinking the “stay and defend” program. John thought that his time there was good but intense and looks forward to another trip to the “Land Down Under.”