The Ecology of the Australian Landscape Fire To commence this topic we will look first at a specific fire event. The 2009 Fires that destroyed Marysville Background A week before the fires, an exceptional heatwave affected South eastern Australia. From 28–30 January, Melbourne broke records by sweltering through three consecutive days above 43 °C, with the temperature peaking at 45.1 °C on 30 January, the third hottest day in the city's history. Marysville

The heatwave was caused by a slow moving high-pressure system that settled over the Tasman Sea, with a combination of an intense tropical low located off the North West Australian coast and a monsoon trough over northern Australia, which produced ideal conditions for hot tropical air to be directed down over southeastern Australia. A pressure system is a region of the Earth's atmosphere where air pressure is a relative peak or lull in the sea level pressure distribution. The surface pressure at sea level varies minimally, with the lowest value measured 870.0 hectopascals and the highest recorded 1,085.7 hectopascals.

You can see a low Pressure system Over the ocean Above are diagrams showing how these systems operate (northern hemisphere)

The fire that destroyed Marysville started about 30kms away. According to eyewitnesses, the Murrindindi Mill fire started at 2:55 pm, while Victoria Police twice told the Royal Commission that it commenced at "about 2.30 pm". It burned southeast across the Black Range, parallel to the Kilmore fire, towards Narbethong. Experienced Air Attack Coordinator Shaun Lawlor reported flame heights of "at least 100 metres" as the fire traversed the Black Range. At Narbethong, it destroyed 95 per cent of the town's houses. When the southerly change struck, it swept towards the town of Marysville.

Fire Front

Hills behind Marysville

Look out from King Lake

Bush fires are a very real and present dangers to people living in the bush These are some of the biggest but every year we have some sort of fire event in Victoria. 1851: 6 February 'Black Thursday' Fires covered a quarter of what is now Victoria (approximately 5 million hectares). Areas affected include Portland, Plenty Ranges, Westernport, the Wimmera and Dandenong districts. Approximately 12 lives, one million sheep and thousands of cattle were lost. 1939: 13 January 'Black Friday' From December 1938 to January 1939, fires burnt 1.5 to 2 million hectares, including 800,000 hectares of protected forest, 600,000 hectares of reserved forest and 4,000 hectares of plantations. The fire severity peaked on Friday January 13 - "Black Friday". The fires caused seventy one fatalities and destroyed more than 650 buildings and the township of Narbethong. The findings of the Royal Commission that was held following the fires were highly significant in increasing fire awareness and prevention throughout Australia.

1983: 16 February 'Ash Wednesday' Australia’s most well-known bushfire event. Over 100 fires in Victoria burnt 210,000 hectares and caused forty seven fatalities. More than 27,000 stock and 2,000 houses were lost. Areas severely affected included Monivae, Branxholme, East Trentham, Mt Macedon, the Otway Ranges, Warburton, Belgrave Heights, Cockatoo, Beaconsfield Upper and Framlingham (see also Ash Wednesday pages). 2009: 7 February 'Black Saturday' On 7 February 2009, Victoria was devastated by the worst bushfires in Australia’s history when 173 people lost their lives. Around 78 communities were directly impacted and entire towns were left unrecognisable. The fires burnt more than 2,000 properties and 61 businesses. Police stations, schools and kindergartens, fire and emergency services facilities, churches, community halls and sporting clubs were also destroyed or badly damaged. Almost 430,000 hectares of land were directly affected, including 70 national parks and reserves and over 3,550 agricultural facilities. Maps have been produced showing the extent of areas affected by these fires.

1851 Area – 5000,000 Ha Buildings - ? Live Stock - 1000,000 Fatalities - 12 1939 Area – 2000,000 Ha Buildings - 650 Live Stock - ? Fatalities - 71 1983 Area – 210,000 Ha Buildings - 2000 Live Stock - 27000 Fatalities - 47 Melbourne and Suburbs 2009 Area – 430,000 Ha Buildings - 2061 Live Stock - ? Fatalities - 173 880,000 Ha

A few months after the fires at Marysville What do you see?

Research For each of these fire events, 1851, 1939, 1983 & 2009 what were the weather conditions on the day & how were they similar? What part does wind play in a bush fire. Given and example from the Marysville fire What is humidity and what effect does it have on conditions necessary for a fire? What are the other conditions must be present for a bush fire to happen? During the 2009 fires Australia was in the grip of what sort of climatic condition? How long had it lasted and what was it's cause?