Climate Change and the Australian Bushfire Threat
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BE PREPARED: CLIMATE CHANGE AND THE AUSTRALIAN BUSHFIRE THREAT The Climate Council is an independent, crowd-funded organisation providing quality information on climate change to the Australian public. CLIMATECOUNCIL.ORG.AU BE PREPARED: CLIMATE CHANGE AND THE AUSTRALIAN BUSHFIRE THREAT Written by Professor Lesley Hughes and Professor Will Steffen. Published by the Climate Council of Australia Limited. ISBN: 978-0-9924142-0-7 (print) 978-0-9924142-1-4 (web) © Climate Council of Australian Ltd 2013. 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 Australian Bushfire Threat by Professor Lesley Hughes and Professor Will Steffen (Climate Council). © Climate Council of Australia Limited 2013. Permission to use third party copyright content in this publication can be sought from the relevant third party copyright owner/s. WARNING: This report may contain the images of Aboriginal and Torres Strait Islander people now deceased. This report is printed on 100% recycled paper. CLIMATECOUNCIL.ORG.AU Preface This is the first major report of the Climate Council, established in September 2013 to replace the former Climate Commission. The Climate Council is an independent, non-profit organization, funded by donations from the public. Our mission is to provide authoritative, expert information to the Australian public on climate change. Over the past year, record-breaking and their impacts. A reference list is temperatures have been experienced provided at the end of this report for across the country. More than 120 those that would like more information. weather records were broken last summer, including the hottest summer, We are very grateful to our team of the hottest January, and the hottest day. expert and community reviewers: Prof. 2013 is on track to become Australia’s David Bowman (University of Tasmania), warmest year on record. These trends, Prof. Ross Bradstock (University of together with below-average rainfall in Wollongong), Mr Ron Collins, Dr Ryan many parts of the country including the Crompton (Risk Frontiers, Macquarie southeast, indicated that the coming University), Mrs Jill Dumsday, Mr David summer fire season was likely to be a Harper, Dr Fay Johnston (University serious one. We thus made the decision of Tasmania), Assoc. Prof. Michelle in September to focus our first report Leishman (Macquarie University), and Dr on bushfires and their link to climate Peter Smith. We are also grateful for the change. This decision was, unfortunately, contribution of Climate Council staff, in borne out by the events in NSW in early particular Katherine Hall, in drafting the October, where intense and uncontrolled report. fires raged across parts of the Central Coast and the Blue Mountains. The authors retain sole responsibility for the content of the report. The October bushfires focused the world’s attention on Australia, with many questions being asked in the community about the link between these fires and climate change. We have Professor Lesley Hughes aimed to provide an up-to-date and Climate Councillor comprehensive summary of this link. We have drawn heavily on the peer-reviewed scientific literature, as well as on submissions to several recent enquiries Professor Will Steffen and Royal Commissions into bushfires Climate Councillor CLIMATECOUNCIL.ORG.AU BE PREPARED: CLIMATE CHANGE AND THE AUSTRALIAN BUSHFIRE THREAT CLIMATECOUNCIL.ORG.AU Contents Preface Key messages Introduction 1 1. The nature of bushfires in Australia ................................................................................ 2 In Detail 1: Forest fire danger index 7 2. Impacts of bushfires ............................................................................................................. 8 2.1 Human health 11 2.2 Built environment and infrastructure 13 2.3 Agriculture 16 2.4 Water 17 2.5 Biodiversity 18 3. What is the link between bushfires and climate change? .......................................22 3.1 Ignition 24 3.2 Fuel 25 3.3 Weather 26 4. Observations of changing bushfire danger weather in Australia .........................28 In Detail 2: Prescribing burning as a management tool 32 5. Has there already been a trend in bushfire activity? .................................................34 5.1 Global trends 35 5.2 Australian trends 37 6. The impacts of fire on the climate system ...................................................................38 7. Fire in the future .................................................................................................................42 7.1 General and global projections 43 7.2 Projections for Australia 45 7.3 Implications of increasing fire activity 48 8. This is the Critical Decade ...............................................................................................50 References 53 Fire danger rating / Preparing for a bushfire 62 CLIMATECOUNCIL.ORG.AU BE PREPARED: CLIMATE CHANGE AND THE AUSTRALIAN BUSHFIRE THREAT Key findings 1. Climate change is already › The fire season will continue to increasing the risk of lengthen into the future, further bushfires. reducing the opportunities for safe hazard reduction burning. › Extreme fire weather has increased over the last 30 years in southeast › One analysis indicated that under Australia. a relatively modest warming scenario, the area of prescribed › Hot, dry conditions have a major burning in the Sydney region influence on bushfires. Climate would need to increase two- to change is making hot days three-fold to counteract the hotter, and heatwaves longer increased fire activity. Under a and more frequent. Some parts more realistic scenario, the amount of Australia are becoming drier. of hazard reduction will need to These conditions are driving up increase five-fold. the likelihood of very high fire danger weather, especially in the 3. Recent severe fires have been southwest and southeast. influenced by record hot, dry conditions. › Australia is a fire prone country and has always experienced bushfires. › Australia has just experienced All extreme weather events are its hottest 12 months on record. now being influenced by climate NSW has experienced the hottest change because they are occurring September on record, days well in a climate system that is hotter above average in October and and moister than it was 50 years exceptionally dry conditions. These ago. conditions mean that fire risk has been extremely high and we have 2. In southeast Australia the fire already seen severe bushfires in season is becoming longer, NSW in the Central Coast and the reducing the opportunities for Blue Mountains. hazard reduction burning. › The Black Saturday fires in Victoria › These changes have been most were preceded by a decade-long marked in spring, with fire weather drought with a string of record extending into October and March. hot years, coupled with a severe CLIMATECOUNCIL.ORG.AU Key findings heatwave in the preceding week. › As fire risk increases, disaster The previous record for the Forest risk reduction and adaptation Fire Danger Index was broken by policies will play a critical role such an extent that it was revised in reducing risks to people and and the category “Catastrophic” or their assets. Increased resources “Code Red” was added. for our emergency services and fire management agencies will be › Since 2009 there have been a required. number of subsequent declarations of Catastrophic conditions around › One estimate of the future southern Australia in step with the economic costs of bushfires hotter and drier climate. indicates that with no adaptive change, increased damage to the 4. In the future, Australia is agricultural industry in Victoria very likely to experience an by 2050 could add $1.4 billion to increased number of days existing costs. with extreme fire danger. › By 2030, it has been estimated › Fire frequency and intensity is that the number of professional expected to increase substantially firefighters will need to in coming decades, especially approximately double (compared to in those regions currently most 2010) to keep pace with increased affected by bushfires, and where population, asset value, and fire a substantial proportion of the danger weather. Australian population lives. 6. This is the critical decade. 5. It is crucial that communities, emergency services, health › Australia must strive to cut services and other authorities emissions rapidly and deeply to prepare for the increasing join global efforts to stabilise the severity and frequency of world’s climate and to reduce the extreme fire conditions. risk of even more extreme events, including bushfires. CLIMATECOUNCIL.ORG.AU BE PREPARED: CLIMATE CHANGE AND THE AUSTRALIAN BUSHFIRE THREAT Introduction Australians have often experienced the serious consequences of bushfires. Over the past decade alone, large and uncontrollable fires devastated several suburbs in Canberra (2003), took 173 lives and destroyed over 2,000 homes in Victoria and Western Australia (2009), and destroyed