Climate Change and the South Australia Bushfire Threat
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BE PREPARED: CLIMATE CHANGE AND THE SOUTH AUSTRALIA BUSHFIRE THREAT The Climate Council is an independent, crowd-funded organisation providing quality information on climate change to the Australian public. CLIMATECOUNCIL.ORG.AU Authorship: Professor Lesley Hughes Published by the Climate Council of Australia Limited ISBN: 978-0-9941866-1-4 (print) 978-0-9941866-0-7 (web) © Climate Council of Australia Ltd 2014 This work is copyright the Climate Council of Australia Ltd. All material contained in this work is copyright the Climate Council of Australia Ltd except where a third party source is indicated. Climate Council of Australia Ltd copyright material is licensed under the Creative Commons Attribution 3.0 Australia License. To view a copy of this license visit http://creativecommons.org.au You are free to copy, communicate and adapt the Climate Council of Australia Ltd copyright material so long as you attribute the Climate Council of Australia Ltd and the authors in the following manner: Be Prepared: climate change and the South Australia bushfire threat by Professor Lesley Hughes (Climate Council of Australia). © Climate Council of Australia Limited 2014. Permission to use third party copyright content in this publication can be sought from the relevant third party copyright owner/s. This report is printed on 100% recycled paper. Professor Lesley Hughes Climate Councillor Introduction Residents of South Australia have We first describe the background experienced the serious consequences context of fire and its history in South of bushfires. In 2005 the Black Tuesday Australia. We then outline the link bushfires on the Eyre Peninsula between bushfires and climate change, resulted in the tragic loss of nine lives before considering how bushfire danger and estimated damages of $41 million weather is increasing in South Australia (2011$). At the beginning of 2014 several and what this means for the immediate bushfires raged across the state, burning future. We explore the impacts of fire tens of thousands of hectares of land, on people, property, water supply and destroying properties and injuring biodiversity, before considering the firefighters and residents. future influence of climate change on bushfires, and the implications for South Australians have always lived with Australian fire managers, planners and fire and its consequences, but climate emergency services. change is increasing fire danger weather and thus the risk of fires. It is time to think very seriously about the risks that future fires will pose. CLIMATECOUNCIL.ORG.AU Page 1 BE PREPARED: CLIMATE CHANGE AND THE SOUTH AUSTRALIA BUSHFIRE THREAT Key Findings 1. Climate change is already › The fire season will continue to increasing the risk of lengthen into the future, straining bushfires in South Australia. South Australia’s existing resources for fighting and managing fires. › Extreme fire weather has increased over the last 30 years in South 3. Recent severe fires in Australia. South Australia have been influenced by record hot, › Australia is a fire prone country dry conditions. and South Australia has always experienced bushfires. Today › Record breaking heat and hotter climate change is making hot weather over the long term in days hotter, and heatwaves South Australia has worsened longer and more frequent, with fire weather and contributed to increasing drought conditions in an increase in the frequency and Australia’s southeast. The hotter, severity of bushfires. drier conditions are increasing the › In January 2005, temperatures of risk of high fire danger weather in over 40°C contributed to severe South Australia. bushfires on the Eyre Peninsula, › 2013 was South Australia’s hottest which resulted in the tragic loss of year on record and in Adelaide the nine lives and estimated damages average intensity of heatwaves of $41 million (2011$). has increased by 2.5°C. These 4. The total economic costs of conditions are driving up the the South Australian bushfires likelihood of very high fire danger in 2014 are projected to be weather in the state. $44 million. By around the 2. The fire season in South middle of the century these Australia is starting earlier cost will almost double. and lasting longer. Fire › Bushfires cause significant weather has been extending economic damage, estimated at into Spring and Autumn. $337 million per year (2011$) in › This year, the bushfire season Australia. With a forecast growth will start early in seven of fifteen in costs of 2.2% annually between districts in South Australia. These 2014 and 2050, the total economic districts include the Eastern Eyre cost of bushfires is expected to Peninsula, Kangaroo Island, the reach $800 million annually by Lower South East, the Mount Lofty mid-century. In South Australia Ranges, the North East Pastoral, bushfires are projected to cost Riverland and the West Coast. $44 million in 2014 (2011$). Page 2 CLIMATECOUNCIL.ORG.AU › These state and national › Increased resources for our projections do not incorporate emergency services and fire increased bushfire incident rates management agencies will be due to climate change and could required as fire risk increases. By potentially be much higher. 2030, it has been estimated that the 5. In the future, South Australia number of professional firefighters in is very likely to experience Australia will need to approximately an increased number of days double (compared to 2010) to keep with extreme fire danger. pace with increased population, asset Communities, emergency value, and fire danger weather. services and health services 6. This is the critical decade across South Australia must › Australia must strive to cut emissions prepare. rapidly and deeply to join global › Fire severity and intensity is efforts to stabilise the world’s climate expected to increase substantially and to reduce the risk of even more in coming decades, especially extreme events, including bushfires. in those regions currently most affected by bushfires, and where a substantial proportion of the Australian population lives, such as South Australia. CLIMATECOUNCIL.ORG.AU Page 3 BE PREPARED: CLIMATE CHANGE AND THE SOUTH AUSTRALIA BUSHFIRE THREAT 1. The nature of bushfires Fire has been a feature of the Australian 75 and 100 considered ‘extreme’. The environment for at least 65 million years unprecedented ferocity of the 2009 Black (Cary et al. 2012). Human management of Saturday bushfires in Victoria saw a new fires also has a long history, starting with ‘catastrophic’ category added to the FFDI fire use by indigenous Australians (“fire- for events exceeding the existing scale. stick farming”) up to 60,000 years ago. The concept of “fire regimes” is Between 3% and 10% of Australia’s land important for understanding the area burns every year (Western Australian nature of bushfires in Australia, and Land Information Authority 2013). for assessing changes in fire behaviour In Australia, the Forest Fire Danger caused by both human and climatic Index (FFDI) is used to measure the factors (Figure 2). A fire regime describes degree of risk of fire in our forests a recurrent pattern of fire, with the most (Luke and Macarthur 1978). The important characteristics being the Bureau of Meteorology (BoM) and fire frequency, intensity, and seasonality management agencies use the FFDI of the fire. Significant changes in any to assess fire risk and issue warnings. of these features of a fire regime can The index was originally designed on a have a very important influence on scale from 0 to 100, with fires between its ecological and economic impacts (Williams et al. 2009). Figure 1: A Firefighter at work in South Australia Page 4 CLIMATECOUNCIL.ORG.AU 01 THE NATURE OF BUSHFIRES IN AUSTRALIA Figure 4. Main factors aecting bushfires 3 | People Main factors Fires may be deliberately started (arson) or be started by accident (e.g. by powerline fault). Human aecting activities can also reduce fire, either by direct suppression or by reducing fuel load by bushfires prescribed burning 1 | Ignition Fires can be started by lightning or people, either deliberately or accidentally 2 | Fuel Fires need fuel of sucient quantity & dryness. A wet year creates favourable conditions for vegetation growth. If 4 | Weather this is followed by a dry Fires are more likely to spread on hot, dry, season or year, fires are windy days. Hot weather also dries out fuel, more likely to spread and favouring fire spread and intensity become intense Figure 2: Main Factors Affecting Bushfires CLIMATECOUNCIL.ORG.AU Page 6 Fire is a complex process that is very of weather that affect fire and fuels are variable in space and time. A fire needs to temperature, precipitation, wind and be started (ignition), it needs something humidity. Once a fire is ignited, very to burn (fuel) and it needs conditions hot days with low humidity and high that are conducive to its spread (weather winds are conducive to its spread. The and topography) (see Figure 2). Fire type, amount, and moisture level of fuel activity is strongly influenced by available are also critical determinants weather, fuel, terrain, ignition agents of fire behaviour, extent and intensity. and people. The most important aspects The relationship between rainfall and CLIMATECOUNCIL.ORG.AU Page 5 BE PREPARED: CLIMATE CHANGE AND THE SOUTH AUSTRALIA BUSHFIRE THREAT fuel is complex. Wet seasons can lead about every 5 to 30 years, with spring to increased plant growth and therefore and summer being peak fire season increase fuel buildup in the months or (Clarke et al. 2011; Bradstock et al. 2012). years before a fire is ignited (Bradstock People are also a very important et al. 2009). Warmer temperatures and component of the fire equation. low rainfall in the period immediately Many fires are either deliberately or preceding an ignition, however, can lead accidentally lit, and in places where to drier vegetation and soil, making the population density is high, the existing fuel more flammable.