BE PREPARED: CLIMATE CHANGE AND THE ACT 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: Lesley Hughes and Will Steffen Published by the Climate Council of Australia Limited ISBN: 978-0-9941623-3-5 (print) 978-0-9941623-2-8 (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 ACT bushfire threat by Lesley Hughes and Will Steffen (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 Professor Will Steffen Climate Councillor Introduction Residents of the Australian Capital We first describe the background Territory (ACT) have experienced the context of fire and its history in the ACT serious consequences of bushfires. and the surrounding region. We then In 2003 large and uncontrollable fires outline the link between bushfires and devastated several suburbs in Canberra, climate change, before considering how claiming five lives and destroying over bushfire danger weather is increasing 500 properties. in the ACT and what this means for the immediate future. We explore the Australians have always lived with impacts of fire on people, property, fire and its consequences, but climate water supply and biodiversity, before change is increasing fire danger weather considering the future influence of and thus the risk of fires. It is time to climate change on bushfires, and the think very seriously about the risks that implications for ACT fire managers, future fires will pose. planners and emergency services. CLIMatECOUNCIL.ORG.AU Page 1 BE PREPARED: CLIMATE CHANGE AND THE ACT BUSHFIRE THREAT Key Findings 1. Climate change is already 2. In the ACT the fire season increasing the risk of is starting earlier and bushfires in the ACT. lasting longer. › Extreme fire weather has increased › During spring in the southeast over the last 30 years in southeast of Australia, fire weather has Australia, including the ACT and been extending into October, surrounding region. and in the autumn, into March. The fire season will continue to › Hot, dry conditions have a major lengthen into the future, further influence on bushfires. Climate reducing the opportunities for change is making hot days safe hazard reduction burning. hotter, and heatwaves longer and This has significant implications more frequent, with increasing for fire services and complicates drought conditions in Australia’s the management of bushfires southeast. 2013 was Australia’s in Australia. hottest year on record and in the summer of 2013/14 Canberra 3. Severe fires in the ACT have experienced 20 days of at least already been influenced by 35°C. These conditions are driving record hot, dry conditions up the likelihood of very high fire with significant consequences danger weather in the Territory. for life and property. › Australia is a fire prone country and › Record breaking heat and a the ACT has always experienced continued warming trend in the bushfires. Today hotter and drier ACT has worsened fire weather conditions are increasing the risk and contributed to an increase of high fire danger weather. in the frequency and severity of bushfires in the Territory and surrounding regions. Page 2 CLIMatECOUNCIL.ORG.AU › In 2003 abnormally high 5. It is crucial that ACT temperatures and below-average communities, emergency rainfall in and around the ACT services, and health services preceded bushfires that devastated prepare for the increasing several suburbs, destroyed over severity and frequency of 500 properties and claimed extreme fire conditions. five lives. This also had serious › As fire risk increases, disaster risk economic implications for the reduction will play a critical role Territory with insured losses of in reducing risks to people and $660 million ($2011). their assets. Increased resources 4. In the future, the ACT is for our emergency services and very likely to experience an fire management agencies will increased number of days be required. with extreme fire danger. › By 2030, it has been estimated › Fire severity across southern that the number of professional Australia has been persistently firefighters in Australia will higher than the long-term average, need to approximately double and the concept of a ‘normal’ (compared to 2010) to keep pace bushfire season is rapidly changing with increased population, asset as bushfires continue to increase value, and fire danger weather. in number, burn for longer, and 6. This is the critical decade affect larger areas. › To reduce the risk of even › Fire frequency and intensity is more extreme events, including expected to increase substantially bushfires, in the future, Australia in coming decades. must cut greenhouse gas › This will have far reaching emissions rapidly and deeply implications for ACT properties, to join global efforts to stabilise agriculture, emergency services the world’s climate. and lives. CLIMatECOUNCIL.ORG.AU Page 3 BE PREPARED: CLIMATE CHANGE AND THE ACT BUSHFIRE THREAT 1. The nature of bushfires Fire has been a feature of the Australian an ignition, however, can lead to environment for at least 65 million years drier vegetation and soil, making the (Cary et al., 2012). Human management existing fuel more flammable. Warmer of fires also has a long history, starting temperatures can also be associated with fire use by indigenous Australians with a higher incidence of lightning (“fire-stick farming”) up to 60,000 years activity (Jayaratne and Kuleshov, 2006), ago. Today between 3% and 10% of increasing the risk of ignition. Australia’s land area burns every year The concept of “fire regimes” is also (Western Australian Land Information important for understanding the Authority 2013). nature of bushfires in Australia, and Fire is a complex process that is very for assessing changes in fire behaviour variable in space and time. A fire needs to caused by both human and climatic be started (ignition), it needs something factors (Figure 1). A fire regime describes to burn (fuel) and it needs conditions a recurrent pattern of fire, with the most that are conducive to its spread (weather important characteristics being the and topography) (see Figure 1). Fire frequency, intensity, and seasonality activity is strongly influenced by of the fire. Significant changes in any weather, fuel, terrain, ignition agents of these features of a fire regime can and people. The most important aspects have a very important influence on of weather that affect fire and fuels are its ecological and economic impacts temperature, precipitation, wind and (Williams et al. 2009). humidity. Once a fire is ignited, very hot In Australia’s southeast, fires are days with low humidity and high winds common in the heathlands and dry are conducive to its spread. sclerophyll forests, typically occurring The type, amount, and moisture about every 5 to 30 years, with spring level of fuel available are also critical and summer being peak fire season determinants of fire behaviour, extent (Clarke et al. 2011; Bradstock et al. 2012). and intensity. The relationship between Canberra is no stranger to bushfires. rainfall and fuel is complex. Wet The ‘Bush Capital’ has been affected by seasons can lead to increased plant bushfires throughout history and much growth and therefore increase fuel of the native vegetation is fire prone, buildup in the months or years before particularly the dry forest, grassland and a fire is ignited (Bradstock et al. 2009). woodland. For example, in 1982–83, Warmer temperatures and low rainfall bushfires broke out amidst a severe in the period immediately preceding drought, burning 33,000 hectares of land. Page 4 CLIMatECOUNCIL.ORG.AU Figure 1: Main Factors Affecting Bushfires The Black Christmas bushfires in NSW droughts in history, burning nearly 70% and the ACT in 2001 caused $131 million of land in Canberra, damaging 90% of ($2011) in insured costs and burned Namadgi National Park, destroying over 753,314 hectares of land (Deloitte Access 500 houses and damaging a further 315 Economic 2014). The major bushfires of (ACT RFS 2011; ABS 2006). 2003 were preceded by one of the worst CLIMatECOUNCIL.ORG.AU Page 5 BE PREPARED: CLIMATE CHANGE AND THE ACT BUSHFIRE THREAT 2. Observations of changing bushfire danger weather in the ACT In Australia, the Forest Fire Danger Index in the ACT. The southeast of Australia (FFDI) is used an indicator for extreme has experienced significant warming fire weather (Luke and Macarthur 1978). during the last 50 years (Timbal et al. The Bureau of Meteorology (BoM) 2012). The number of heatwave days in and fire management agencies use Canberra has doubled since 1950 and the FFDI to assess fire risk and issue the increase in hot weather that was warnings. The index was originally observed in the 2000–2009 decade has designed on a scale from 0 to 100, with already reached the level previously a value between 75 and 100 considered projected for 2030 in Canberra (BoM ‘extreme’. The unprecedented weather 2013a; Climate Council 2013b). conditions that triggered the 2009 Increasing heat persisted into 2013. Black Saturday bushfires in Victoria saw Last year was Australia’s hottest year a new ‘catastrophic’ category added on record and the mean maximum to the FFDI for weather conditions temperature during the year was 1.45°C exceeding the existing scale.