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Article | WTW Research Network Newsletter

Fanning the flames of wildfires: COVID-19 and climate change

By Hélène Galy | August 25, 2020

Wildfires provide an interesting lens to understand those real-world interactions between risks, which could make things much worse than standalone models predict.
Climate|Willis Research Network
Climate Risk and Resilience|COVID 19 Coronavirus|Climate and Resilience Hub

Cascading, compound and interconnected risksi are all around us – yet, they are still rarely captured explicitly by catastrophe models, which largely focus on a single peril. In some cases, combined impacts may be partially and implicitly represented in models, given that the claims used for calibration may cover multiple perils (e.g. claims from inland flooding and storm surge caused by tropical stormsii), but explicit understanding and acknowledgement of these interactions will support resilience.

In a recent report, 222 scientists across 52 countries highlighted cascading crisis as the biggest threat to planetary health and future generationsiii. The COVID-19 pandemic has exposed many examples of those complexities, not least when it comes to floodingiv. A number of climate-related hazards are and will intersect with the pandemic, and they will test governments’ ability to cope with compound risksv. Another consideration is demand surge: demand for reconstruction material and labour after a natural disaster can typically, surge 15-30%, and last for a year, and this could be compounded by this pandemicviviiviii.

Wildfires are an interesting lens to consider interactions between risks, which could make things much worse than standalone models predict, and failure to stress test this approach may not leave enough of a gap to stop or mitigate cascading effects.

COVID-19, adding fuel to the (wild)fire.

Against a 5-year average of 3,645 fires for the January – July period, California has already experienced 5,006 fires in 2020ix. NOAA's Climate Prediction Center forecasts drought conditions for California through Octoberx. The National Interagency Fire Center predicts this year’s fire season will see an above average number of fires in the Southwest and Pacific Northwestxi. This summer could also be the hottest on record, as seen in the new hottest temperature on earth recorded in Death Valley in Augustxii.

For the Californian wine industry, this could be another blow after the heavy toll of the pandemic on their revenue, as reported by the Wine Business Institutexiii. A $4.2 billion loss in wine business revenues may create a tax loss of $586 million for state and local governments in 2020. Wildfires at the wrong time (before the harvest) could make a bad situation worse.

Even before the wildfire season began in the US, the usual mitigation strategy had already been derailed. Controlled burns were suspended in many states. Projects intended to help homeowners reduce their vulnerability were often paused. Investment in resilience (e.g. retrofitting homes) is worthwhile, with estimates of $1 spent now saving $6 in future emergenciesxiv.

The wildfire situation is further complicated by the current pandemic, in a complex web of interconnections.

  • California was going to spend billions of dollars to prepare for its fire season and other extreme weather disasters. The infrastructure projects, designed to make communities and homes more resistant to wildfire, have long been overlooked, fire experts say. But with a $54 billion budget deficit, the infrastructure projects have been put on holdxv. Given the critical role of vegetation management and power lines maintenance (to prevent the risk of ignition) highlighted by the 2018 California fires, one wonders how these have been impacted by COVID-19 directly (loss of manpower) and lockdown measures. In the meantime, PG&E have understandably found it difficult to secure a good deal on wildfire insurance, and increased premiums will be partly passed on to customersxvi.
  • The ability for firefighters to respond may also be compromised in many ways: training by Zoom is unlikely to be as effective; physical distancing and quarantining guidelines get in the way of normal operations, which have been adjustedxvii to minimize contact and slow the potential spread of the coronavirus.
  • COVID-19 will also hamper usual collaboration arrangements. Quebec is facing its worse wildfire season in a decade. This season may test the Reciprocal Forest Fire Fighting Agreement that Canada and the US have had for decades. This adds an interesting geopolitical angle, and quarantine agreements or exemptions will need to be considered.
  • The logistics of evacuation plans are even more complicated, to comply with physical distancing. Forget the traditional congregate evacuation centres: sheltering evacuees in local hotels to avoid disease transmission led a Red Cross official to call this “a very expensive Plan B”xviii, and raises complex reputation risks for all involved.
  • Finally, there are also concerns that wildfire smoke can make the pandemic worsexix. A few studies point to the fact that smoke could weaken immune systems, making people more vulnerable to viruses and pathogens: COVID-19 or the yearly fluxx. Similar concerns have been raised about the exacerbating effects of other forms of air pollutionxxi.

These complex interconnected risks are many and varied, and can also become embroiled in feedback loops, when considering the effects of climate change.

Climate change fanning the flames

In the Arctic, soaring temperatures and dry soil have created ideal conditions for fires. June 2020 produced more carbon emissions into the Earth’s atmosphere than in any other month over since 2003xxii. These fires not only release CO2, but other greenhouse gases, such as the more potent methane, and dark aerosol particles can also cause ice to absorb more heat. These effects in turn exacerbate global warming and climate change.

Although it cannot be said that individual events can be wholly ascribed to climate change, given the natural climate variability, attribution science is a growing field of research, which seeks to understand and quantify the contribution of climate change to the frequency and severity of extreme weather and climate events. There is a large consensus that climate change makes heatwaves more likelyxxiii, and possibly longer too. The recent heatwaves and drought in Europe are a much-studied examplexxiv.

The Carbon Brief records and maps all such attribution studiesxxv. For wildfires, out of 11 studies, 10 found a clear influence of human-induced climate change. The 11th study was inconclusive.

Australia’s “Black Summer” bushfires of 2019-2020 are a stark example of how record heat, drought, and low soil moisture made more likely by climate change are conspiring as perfect antecedents to wildfiresxxvi.

A recent study contends that the Siberian heatwave in 2020 would have been almost impossible without climate changexxvii. Heatwaves and drought make wildfires more likely, if fire management can’t reduce the triggers: natural (lightningxxviii), human (arson or careless behaviour) or infrastructure (power lines, transformers). The impact of anthropogenic climate change on fire weather is emerging above natural climate variabilityxxix. This is consistent with the conclusions of the “Fire and Climate Change” summary of the 2019 IPCC Special Report on Climate Change and Landxxx, which also stated that fire weather seasons have lengthened globally between 1979 and 2013.

The peat fires in Siberia are a natural phenomenon less well understood than typical forest fires. Unlike crown fires, peat fires happen largely underground, and can be very difficult to extinguish. There is also evidence of “zombie fires”xxxi, underground dormant fires capable of reigniting after a long period. This will be of interest to Canada (40% of its landmass being in the Artic), but also the UK. The Saddleworth Moor fires of 2018 are amongst the worst fires experienced by the UK and involved peatland. In the UK, wildfires tend to move slowly, and have not killed yet in modern times. Apart from the threat to Queen guitarist Brian May’s home and studio, one of the key concerns from the August 2020 wildfire of heathlands in Surrey, is loss of habitat for wildlife and impact on biodiversity, compounding some effects of climate change. Peat lands take many thousands of years to form and therefore are a limited resource. Their carbon fixing properties also make them a very efficient carbon sink, so peat fires are serious in terms of CO2 balance and emissions.

In emerging economies, wildfires can have a devastating impact, often largely uninsured. In 2015, fire and haze cost Indonesia USD 16bn - twice the cost of reconstruction following the 2004 tsunami. 26% of the costs relate to natural capital, including losses to biodiversity. Losses are mostly driven by lost capacity for carbon storagexxxii. In other areas, the combined impact of COVID-19 and wildfire on indigenous populationsxxxiii is worrying: although only 5% of the world population, they are estimated to protect 80% of the world’s biodiversity.

In Australia, recent fires have affected regions not well adapted to fire, destroying areas historically been too wet to burn, including Queensland’s rainforest in 2018 & 2019, and Tasmanian mountain forest in 2019. The fires in 2019-2020 in south-east Australia were so extensive and unprecedented that entire habitats were threatened. The world heritage “Gondwana rainforests”, a living link to the vegetation that covered the southern supercontinent Gondwana before it broke up about 180m years ago, are now under threatxxxiv.

Expect more cascading risks

Modern societies are now highly dependent on networks, which means that failures can easily propagate through critical infrastructure and supply chains, affecting multiple sectors and geographies. Infrastructure assets are not only exposed to risks, they also create risks and increase exposure. The World Bank has highlighted the contribution of poor quality infrastructure to wildfire risk: in particular the lack of operations and maintenance investment for electricity transmission and distributional lines, creating greater potential for wildfire ignitionxxxv.

This has led researchers at the Cascading Disasters Research Group at UCL to argue that going forward “most disasters will be cascading events to a greater or lesser extent”. Multi-hazard analyses are becoming more common, but an all-encompassing model capturing all those complex relationships remains a utopia, especially given that in many crises, human agency is one of the critical factors.

Indeed, beyond climate change, another key driver for wildfire risk is urban development in fire-prone environments. As highlighted in a recent Willis Re reportxxxvi, the number of houses in the wildland-urban interface, where structures blend with wildland, increased dramatically in recent decades. This is reflected in the wildfire hazard scoring presented in this report.

Scenario and event trees can be a powerful and engaging way to investigate the vulnerability paths by which cascading impacts are propagated. This can support policy and decision making, in particular assessing the preventive or adaptation measures that can be taken to reduce risks in advance and increase resilience of critical assets. The Willis Research Network, with its multi-disciplinary approach, looks to consider challenges from multiple angles. Taking extreme events and stress-testing them, whether through quantitative modelling or qualitative scenarios is one way to build resilience to global, complex risks and decide what to do next.


i What are cascading disasters?



iv Flood impacts compounded by COVID-19


































Managing Director of Willis Research Network
Head of People Risks Research

Hélène joined Willis in 1998, specialising in natural hazard modelling and reinsurance optimisation. Since 2001, she has been leading multi-disciplinary teams, who research, design and develop analytical solutions and insights for risk identification, quantification and management. She currently leads the Willis Research Network, an award-winning public-private partnership, which harnesses over 60 science partners to form innovative long-term collaborations, improving our understanding of risks (natural hazards, technological risks, geopolitical drivers of risk) for the benefit of clients and society: using science to support resilience.
Hélène has extensive experience in spatial modelling, design of innovative solutions, and applying science to business challenges. Her current focus is on Climate advisory services (advising corporates on how leading-edge climate research can help them quantify their exposure to climate variability and climate change; exploring the links between climate change and national security) and on People Risks (how people can increase vulnerability or improve resilience: terrorism, societal resilience to systemic risks, including pandemics).
She holds a BSc in Economics & Political Science (Sciences Po), and an MSc in Environmental Economics (UCL).


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