This week the World Economic Forum again published its Global Risk Report. The report is based on a survey that accesses insights across the Forum’s vast network of business, government and community leaders.
For the third year running, extreme weather was listed as the top global risk in likelihood of occurrence and within the top 5 in impact. Overall, environmental risks dominated the assessment with failure of climate-change mitigation and adaptation and natural disasters also recorded amongst the top risks. These risks were rated above others that commonly occupy the minds of policy makers and the media such as asset bubbles, terrorist attacks, energy price shocks, financial crises and many more. (See Figure 1)
The report expresses rising concerns regarding climate inaction stating that: “of all risks, it is in relation to the environment that the world is most clearly sleepwalking into catastrophe”. The report further reiterates recent messages from the IPCC about the extent of the global struggle to restrict warming and the dire warning by the recent United States National Climate Assessment that without significant reductions in emissions, average temperatures could rise by five degrees Celsius by 2100.
It is claimed that the disruption to the production and delivery of goods and services due to environmental disasters has risen by 29% since 2012, placing additional strain on the resilience of organisations and their customers.
The growing threat of sea level rise and the rising population of coastal megacities globally was featured. Some 800 million people already live in cities vulnerable to sea level rise up to 0.5 metres. According to the World Bank, 70% of the largest cities in Europe are susceptible to sea level rise. The phenomena pose significant risks to properties and infrastructure, though the economic risk globally is concentrated in low-lying coastal areas with significant asset values. The report cites research that $14.1 Billion was lost from home values in parts of the US east coast due to sea level rise between 2005 and 2017.
Cyber risk was also rated highly with both massive data fraud and theft, and cyber-attacks being among the top five risks in likelihood of occurrence. Interestingly, respondents expected that cyber risks would increase in 2019. The associated vulnerabilities of essential infrastructure were a concern given recent examples of hackers gaining access to the control rooms of some utility companies in the United States.
For solutions, the report supports the need for action to rapidly decarbonize agriculture, energy, transport and industry to limit the rise of global temperatures and to establish plans for adaptation. The challenge of promoting proactive adaptation investment is, however, highlighted by citing statistics showing that spending on flood recovery is nine times greater than investment in flood mitigation.
Interestingly the report offers advice on conceptualising the unimaginable through promoting a technique of imagining failure and then thinking why such a failure may have occurred. Doing so is known as “prospective hindsight” and according to psychologists enables us to anticipate a broader and more vivid set of problems.
Risk Frontiers will continue to support our clients in addressing these top risks in 2019 through the continued licensing and development of our suite of natural hazard catastrophe loss models for Australia and New Zealand. Our partnership with the ARC Centre of Excellence for Climate Extremes will allow us to give our clients unique insights into how climate change may affect their business. Furthermore, we will continue our work on building a cyber loss model through the Optus Macquarie University Cyber Security Hub and in assisting Government clients to build safer and more resilient communities in partnership with organisations including the Bushfire and Natural Hazards Cooperative Research Centre.
Hurricane Florence impacted the US East Coast in September 2018 resulting in dangerous surf conditions, strong winds, storm surge and heavy rain producing significant flooding. The system made landfall over North Carolina as a Category 1 hurricane. While 1.7 million people received evacuation orders (The Independent, 2018), estimates of evacuees in shelters were around 30 thousand people (VOA, 2018), and total flood loss for residential and commercial properties in North Carolina, South Carolina and Virginia were estimated to be between $19 billion and $28.5 billion. Around 85 percent of residential loss is estimated to be uninsured (CoreLogic, 2018).
This article aims to identify key circumstances and demographic factors common in those who lost their lives as a result of Hurricane Florence.
We define a hurricane death as one which would not have occurred if the hurricane had not impacted, i.e. any death directly or indirectly caused by that hurricane. This includes deaths from the potential mechanisms of rain (e.g., filling a depression into which an individual may fall and drown) and its associated flooding (riverine, flash), storm surge, strong winds and high seas. It also includes deaths of persons carrying out activities specifically associated with the hurricane – e.g., taking measurements, preparing people, goods or buildings to evacuate or endure the event, and cleaning up after the event (e.g., an accident whilst running a generator that was required because strong winds from the hurricane have taken out the electricity supplies). Care needs to be taken with timing – for example, how long after a hurricane has passed should one attribute flood deaths to that hurricane? This will vary from one event to another and is best defined by the weather authorities as (e.g., for Australia) in the case of a tropical cyclone decaying to a tropical low which can produce rain long after the initial impact of the tropical cyclone.
By searching through articles from numerous media outlets, we have identified 53 hurricane deaths. Where possible, records were verified against multiple news sources. We also classified each record by the state and county in which the death occurred, 10 year age bracket, and by category of cause of death (e.g., deaths occurred while in a vehicle, deaths caused by falling debris). The results are also compared with previous research on fatalities associated with Australian Tropical Cyclones by Coates, et al. (2017).
Results and analysis
The most common circumstances that caused fatalities were related to vehicles (n=26, 49%) and flooding (n=23, 43%). Only one vehicle incident causing multiple deaths was identified. Fourteen (26%) fatalities resulted from vehicles being washed off roads and nine (17%) from vehicles colliding with obstacles due to water on the road causing aquaplaning or heavy rain causing low visibility. Most incidents involved only private vehicles, but two people died when a prison transport van was driven into floodwater and one person died driving a semi-trailer truck which aquaplaned, left the road and struck an undescribed obstacle. Only two flooding related fatalities were not also related to vehicles: a child playing in water which was deeper than normal due to preparatory release from a dam and a man who refused mandatory evacuation and was subsequently trapped in a caravan trailer.
Four people died as a result of a tree falling on their residence or vehicle during the hurricane, while other debris related circumstances included vehicle striking fallen tree, tree falling during clean-up operations and a woman who died after suffering a heart attack as emergency services could not get to her due to debris on roads. Two people died from carbon monoxide poisoning while running a generator indoors due to power outages, while other circumstances relating to death included loss of power for an oxygen concentrator and electrocution while attempting to connect extension cords to a generator in heavy rain. Two people died in a house fire which was caused by candles used after a loss of power. Two people fell from ladders and another person suffered unspecified injuries while cleaning debris from the storm or making repairs. Three people died in circumstances relating to evacuation, one of whom fell while packing for evacuation, one on a moped while evacuating and one who fell and struck his head in a hotel to which he had evacuated.
Victims were most commonly 70 years old and above. No deaths were recorded for people between 10 and 19 years old, but there were a few fatalities under 10 years old. The deaths of those under 10 years old were caused primarily by trees falling on homes, and being in cars that were driven into floodwater by an accompanying adult. Figure 1 shows fatalities in 10-year age categories as a percentage of all fatalities where age was reported.
Males represented 74% of the deaths where the gender of the deceased was specified; however, a higher proportion of females died in circumstances relating to vehicles (58%) compared to males at 35%. More males died in circumstances relating to preparing for, activities during, and clean-up after the event such as checking on possessions, setting up generators, swimming in dangerous conditions or clearing debris.
Discussion and conclusion
The consequences of Hurricane Florence provide a clear reminder of the dangers associated with driving vehicles during and after severe weather, and the importance of avoiding driving through floodwater. Severe weather is shown to increase risks associated with evacuating by vehicle.
Figures 2 and 3 compare key demographics between fatalities from Hurricane Florence and a historical analysis of fatalities due to tropical cyclones in Australia from 1970 to 2015 by Coates, et al. (2017). Our analysis of deaths resulting from Hurricane Florence demonstrates a consistent gender distribution with Australian historical data. This supports the conclusion that males are more likely to be in hazardous situations or undertake risky behaviours than females in these types of events. However, the two data sets differ markedly in age demographics, with much younger victims in Australia than Hurricane Florence.
Coates, L., Haynes, K., Radford, D., D’Arcy, R., Smith, C., van den Honert, R., Gissing, A. 2018. An analysis of human fatalities from cyclones, earthquakes and severe storms in Australia. Report for the Bushfire and Natural Hazard Cooperative Research Centre.
In 2018, Queensland had the third-warmest spring and forth-warmest November on record, in terms of mean temperature (BoM, 2018d). At the end of November, exceptional heat affected eastern Queensland, with some locations reaching their highest annual maximum temperatures ever recorded. Wildfires raged across central Queensland and more than 140 fires were burning throughout the State during the last week of November (BoM, 2018d), due to a combination of the prolonged heatwave and other “unprecedented” conditions. More than a million hectares have been burnt out, with 15 dwellings and more than 60 sheds or other structures being reported as damaged (Caldwell, 2018). Given the human population in the affected area, casualties were light: one man died after being hit by a falling tree while clearing a firebreak at Rolleston in the Central Highlands. All the threatening fires were contained by 5 December, with weather conditions easing due to severe storms sweeping across Queensland. Figure 1 shows all the fire hotspots for Queensland from 26 November to 5 December.
Record-breaking heatwave and catastrophic fire risk
Extreme heatwave conditions started developing in far north Queensland from 23 November 2018, and then spread across the north-east and central regions of the State (Figure 2). This heatwave was unusual as the temperatures were 5-10 °C above the November average, the humidity was exceptionally low for this time of year and the extreme hot conditions extended over a much longer period than “usual” heatwaves. The above-average temperature and unseasonally dry and hot westerly winds led to severe to locally extreme fire danger over large parts of eastern Queensland. The fire danger conditions peaked on 28 November, reaching a catastrophic level for the Capricornia, Central Highlands and Coalfields regions (Figure 3). Cairns hit 42 °C two days (27 & 28 November) in a row, which are the hottest days on record for the region in November.
According to Phoenix fire simulation technology (Figure 4), about 8,000 residents needed to be evacuated from Gracemere, west of Rockhampton. The town was subsequently saved, using a combination of water bombing aircraft and fire-fighting crews on the ground. Another significant bushfire originating in the Deepwater National Park on the central Queensland coast burnt out more than 17,000 hectares and forced hundreds of people to evacuate (Figure 5). This Deepwater blaze was extremely dangerous due to erratic wind direction changes, high fuel loads and low humidity, having a 66-kilometre perimeter and flames up to 10 metres in height (Ferrier et al., 2018).
Comparison with previous bushfire events in Queensland in Risk Frontiers’ natural hazards database (PerilAUS) show that bushfire events around Brisbane, in 1994, also occurred after a heatwave. However, no event in PerilAUS has ever covered such a vast expanse of Queensland as this recent one. And there have been relatively few properties lost in any previous fires.
As discussed in our Briefing Note 381, a heavy rain event on 28 November affected the Illawarra, Sydney Metropolitan and Central Coast areas in New South Wales. At the same time, Queensland was suffering extreme heatwave and fire danger conditions (Figure 6). Sarah Fitton of BoM indicated these two contrasting events were driven by connected systems (Doyle, 2018). Figure 7 shows that the abnormal westerly flow to the north of the low was responsible for the catastrophic fire danger ratings along the tropical QLD coast and it extended down into the low-pressure system across the New South Wales south coast. The two events were linked and influencing each other. The low over New South Wales was pushing warm air and stronger winds to Queensland through the connected system, intensifying fire danger conditions (Yeo, 2018).
When considering these recent fire events in Queensland, it is clear that the catastrophic fire risk is substantially influenced by record extreme weather events. Clarke et al. (2012) has shown increased fire weather conditions in Australia since the 1970s. Unprecedented conditions may become a new normal and peril factors correlating together can worsen local situations.
Risk Frontiers is currently building a new bushfire model using the latest remote sensing technologies and machine learning models. This model, along with Risk Frontiers’ loss models for other meteorological disasters, will soon be correlated on the Multi-Peril Workbench to better price cascading hazards.
The heavy rain event on 28 November 2018 caused widespread flooding in the Illawarra, Sydney Metro and Central Coast areas, with some suburbs experiencing up to 61 mm in 30 minutes in Mosman, over 100 mm in two hours in the Sydney CBD and lower north shore, and 130 mm in 24 hours in Mosman. This type of springtime flash flooding is not uncommon, but is often associated with urban surface water flooding, and not coastal erosion.
From a coastal perspective, it raises an interesting question for erosion of Sydney’s North Shore and Middle Harbour beaches. These areas include some of Sydney’s most expensive residential and commercial property, and are usually regarded as protected, low wave energy beach locations with minimal erosion risk.
However – as demonstrated over the past few days – erosion can occur at these locations, and not necessarily due to waves from the seaward side but from urban stormwater runoff from the landward side (or to complicate things, a combination of both). The primary cause of erosion and consequential infrastructure damage can be important with regards to insurance against ‘actions of the sea’.
Rain then wind then waves
The 28 November rain event developed from a NW-SE oriented trough over the continent, with several low-pressure cells developing 1 – 2 days prior to 28 November (Figure 1, A – C). The deepest of these was centered over coastal NSW, reaching a moderate 994 hPa by the morning of 28 November (Figure 1, D).
The first front and associated rainfall (blue dotted line in Figure 1) passed over the Sydney Harbour area in the early morning of 28 November (6 to 8 AM). There was a maximum of 130 mm of rain in Mosman and 111 mm at The Rocks (Observatory Hill) – more than a month’s volume for these areas. A second front affected Western Sydney in the afternoon of 28 November (Figure 1 F) but did not significantly impact habour beach locations.
Winds were not a key feature of this event and peaked a few hours after the most intense rainfall was experienced on the North Shore – reaching just below 50 km/hr at 10:30 AM on 28 November (BoM Observatory Hill, BoM 2018b).
As the low-pressure cell moved offshore (Figure 1, G – H), rain and wind dropped while wave heights at the open coast began to rise (Figure 1). Observations at the Sydney wave buoy, located approximately 30 km off Narrabeen on Sydney’s Northern Beaches, show waves from the SE peaked in the late afternoon of 28 November, with maximum wave heights reaching between 7 and 10 m (Figure 2).
A different type of East Coast Low
The 28 November event was an East Coast Low (ECL) – but not the type normally associated with coastal erosion. It developed from a continental / inland trough low, typical of a spring-time ECL (Browning and Goodwin, 2013), whereas most highly erosive ECLs occur in the winter months and have a more meridional (shore-parallel) track. The severe weather, while very intense was short lived because of the steady movement of the low.
The heavy rain was driven by intense thunderstorms that formed in the northwest of the Sydney Basin and tracked southeast. According to design rainfall depths, there is only a 1 % chance of this intensity of rainfall on the Lower North Shore (up to 61 mm in 30 minutes in Mosman) occurring in any one year (ARR, 2016). The intense rainfall was probably a result of cooler-than-normal land surface temperatures on the coast and relatively mild ocean temperatures, resulting in strong convection and rainfall (Browning pers. comms.).
This particular event had the characteristics of an extra-tropical cyclone and was driven by the dynamics of the upper atmosphere in a similar way to the mechanism for classic ECL development. Rain and wind were to the south of the centre of the low with clear sky and westerlies to the north.
It was a very unusual weather pattern for late November – the abnormal westerly flow to the north of the low was responsible for the record maximum temperature along the tropical QLD coast and catastrophic fire danger ratings. It’s very hard to get strong surface westerlies at these latitudes at this time of the year. The reason for this may be the unusual amount of Antarctic sea ice for this time of year (Goodwin, pers. comms.), which acts to displace the atmospheric cells in the Southern Hemisphere equatorward.
Causes of coastal erosion
In Sydney Harbour, the main cause of beach erosion was urban stormwater runoff (overland and drainage), not waves – an important distinction for insurance. Balmoral Beach in Mosman is a good example of the vulnerability of these largely protected, low wave energy coastal sites to this type of erosion. A steep, urbanized hinterland directly behind the beachfront led to high flow volumes running down several ‘urban rivers’ towards the beach (Figure 3). This washed out beach sand from the landward side, causing flooding and some significant erosion in places (Figure 4).
It is possible for beaches in Middle Harbour to experience wave-driven coastal erosion. If wave heights outside Sydney Harbour are large, and the wave direction is from the SE, wind-waves can refract into Middle Harbour beaches and cause erosion. Interestingly, even beaches deeper in the harbour can experience erosion during ECLs without being directly exposed to the ocean wind waves. This (hypothetically – not tested) occurs through the propagation of infragravity wave energy – very long period, low amplitude waves that can bounce off headlands to reach otherwise protected locations. This type of wave energy is not detected by conventional wave buoys and is often associated with phenomena such as surf-beat or tsunamis. An example of this was during the April 2015 ECL, when Clontarf Beach – located deep inside Middle Harbour next to Spit Bridge – suffered severe erosion which may have been related to infragravity waves.
Springtime ECLs are most commonly associated with flash flooding, and not coastal erosion because of the predominantly zonal track and limited wind and wave component of these events. 28 November, however, was a reminder that coastal erosion is not just caused by ‘actions of the sea’ but can result from a combination of heavy rainfall and a steep, urbanized hinterland. Fortunately, this type of rainfall is often localized – but it can lead to beach loss and infrastructure damage in some surprising places.
Risk Frontiers is currently building an East Coast Low loss model to assist insurers to price risk during these types of events.
Paul Somerville and Thomas Mortlock, Risk Frontiers
The U.S. federal government on Friday 23 November released a long-awaited report (NCA4) with an unmistakable message: the effects of climate change, including deadly wildfires, increasingly debilitating hurricanes and heat waves, are already battering the United States, and the danger of more such catastrophes is worsening. The report’s authors, who represent numerous federal agencies, say they are more certain than ever that climate change poses a severe threat to Americans’ health and pocketbooks, as well as to the country’s infrastructure and natural resources. And while it avoids policy recommendations, the report’s sense of urgency and alarm stands in stark contrast to the lack of any apparent plan from President Trump to tackle the problems, which, according to the government he runs, are increasingly dire.
The congressionally mandated document, the first of its kind issued during the Trump administration, details how climate-fueled disasters and other types of changes are becoming more commonplace throughout the country and how much worse they could become in the absence of efforts to combat global warming.
The Fourth National Climate Assessment (NCA4) contains two volumes. Volume II draws on the foundational science described in Volume I, the Climate Science Special Report (CSSR).Volume II focuses on the human welfare, societal, and environmental elements of climate change and variability for 10 regions and 18 national topics, with particular attention paid to observed and projected risks, impacts, consideration of risk reduction, and implications under different mitigation pathways. Where possible, NCA4 Volume II provides examples of actions underway in communities across the United States to reduce the risks associated with climate change, increase resilience, and improve livelihoods.
The report concludes that Earth’s climate is now changing faster than at any point in the history of modern civilization, primarily as a result of human activities. The impacts of global climate change are already being felt in the United States and are projected to intensify in the future—but the severity of future impacts will depend largely on actions taken to reduce greenhouse gas emissions and to adapt to the changes that will occur. The following summary information is excerpted from the report.
1. Key Scientific Advances
The following scientific advances have been made since the previous assessment (NCA3) in 2014.
Detection and Attribution: Significant advances have been made in the attribution of the human influence for individual climate and weather extreme events.
Extreme Events and Atmospheric Circulation: How climate change may affect specific types of extreme events in the United States and the extent to which atmospheric circulation in the midlatitudes is changing or is projected to change, possibly in ways not captured by current climate models, are important areas of research where scientific understanding has advanced.
Localized Information: As computing resources have grown, projections of future climate from global models are now being conducted at finer scales (with resolution on the order of 15 miles), providing more realistic characterization of intense weather systems, including hurricanes. For the first time in the NCA process, sea level rise projections incorporate geographic variation based on factors such as local land subsidence, ocean currents, and changes in Earth’s gravitational field.
Ocean and Coastal Waters: Ocean acidification, warming, and oxygen loss are all increasing, and scientific understanding of the severity of their impacts is growing. Both oxygen loss and acidification may be magnified in some U.S. coastal waters relative to the global average, raising the risk of serious ecological and economic consequences.
Rapid Changes for Ice on Earth: New observations from many different sources confirm that ice loss across the globe is continuing and, in many cases, accelerating. Since NCA3, Antarctica and Greenland have continued to lose ice mass, with mounting evidence that mass loss is accelerating. Observations continue to show declines in the volume of mountain glaciers around the world. Annual September minimum sea ice extent in the Arctic Ocean has decreased at a rate of 11%–16% per decade since the early 1980s, with accelerating ice loss since 2000. The annual sea ice extent minimum for 2016 was the second lowest on record; the sea ice minimums in 2014 and 2015 were also among the lowest on record.
Potential Surprises: Both large-scale shifts in the climate system (sometimes called “tipping points”) and compound extremes have the potential to generate outcomes that are difficult to anticipate and may have high consequences. The more the climate changes, the greater the potential for these surprises.
2. Extreme Events
Climate change is altering the characteristics of many extreme weather and climate-related events. Some extreme events have already become more frequent, intense, widespread, or of longer duration, and many are expected to continue to increase or worsen, presenting substantial challenges for built, agricultural, and natural systems. Some storm types such as hurricanes, tornadoes, and winter storms are also exhibiting changes that have been linked to climate change, although the current state of the science does not yet permit detailed understanding. Individual extreme weather and climate-related events—even those that have not been clearly attributed to climate change by scientific analyses—reveal risks to society and vulnerabilities that mirror those we expect in a warmer world. Non-climate stressors (such as land-use changes and shifting demographics) can also amplify the damages associated with extreme events. The National Oceanic and Atmospheric Administration estimates that the United States has experienced 44 billion-dollar weather and climate disasters since 2015 (through April 6, 2018), incurring costs of nearly $400 billion (https://www.ncdc.noaa.gov/billions/).
3. Reducing Risks through Adaptation Actions
Key Message 1: Adaptation Implementation Is Increasing Adaptation planning and implementation activities are occurring across the United States in the public, private, and nonprofit sectors. Since the Third National Climate Assessment, implementation has increased but is not yet commonplace.
Key Message 2: Climate Change Outpaces Adaptation Planning Successful adaptation has been hindered by the assumption that climate conditions are and will be similar to those in the past. Incorporating information on current and future climate conditions into design guidelines, standards, policies, and practices would reduce risk and adverse impacts.
Key Message 3: Adaptation Entails Iterative Risk Management Adaptation entails a continuing risk management process; it does not have an end point. With this approach, individuals and organizations of all types assess risks and vulnerabilities from climate and other drivers of change (such as economic, environmental, and societal), take actions to reduce those risks, and learn over time.
Key Message 4: Benefits of Proactive Adaptation Exceed Costs Proactive adaptation initiatives—including changes to policies, business operations, capital investments, and other steps—yield benefits in excess of their costs in the near term, as well as over the long term. Evaluating adaptation strategies involves consideration of equity, justice, cultural heritage, the environment, health, and national security.
Key Message 5: New Approaches Can Further Reduce Risk Integrating climate considerations into existing organizational and sectoral policies and practices provides adaptation benefits. Further reduction of the risks from climate change can be achieved by new approaches that create conditions for altering regulatory and policy environments, cultural and community resources, economic and financial systems, technology applications, and ecosystems.
USGCRP, 2018: Impacts, Risks, and Adaptation in the United States: Fourth National Climate Assessment, Volume II: Report-in-Brief [Reidmiller, D.R., C.W. Avery, D.R. Easterling, K.E. Kunkel, K.L.M. Lewis, T.K. Maycock, and B.C. Stewart (eds.)]. U.S. Global Change Research Program, Washington, DC, USA, 186 pp.
Twenty-eight years on from the First Assessment Report in 1990, the IPCC’s most recent Special Report on Global Warming delivers an urgent warning to policymakers that we are reaching the point of no return for mitigating anthropogenic impacts on global warming and associated climate change. The report has divided opinion in Australia and further highlights the discord between climate science, economics and politics nationally.
The report finds that limiting global warming to 1.5°C would now require rapid and unprecedented change in all aspects of society. The report highlights that we are already seeing the consequences of 1°C of global warming through more extreme weather, rising sea levels and diminishing Arctic sea ice.
While 1.5°C may seem a small increase, it is how changes in mean temperatures are related to extreme weather events that is important.
A small increase in the mean temperature also shifts the tails of the distribution, meaning it may impact extreme weather events that are temperature-dependent. However, any relationship between increasing mean global air temperature and extreme weather will be complex, and both peril and location-dependent.
Prof Andy Pitman, from the University of New South Wales and Director of the ARC Centre of Excellence for Climate Extremes, described this in an anecdote to BBC News back in January:
“the probability works a bit like if you stand at sea level and throw a ball in the air, and then gradually make your way up a mountain and throw the ball in the air again. The chances of the ball going higher increases dramatically. That’s what we’re doing with temperature.”
As an industry partner of the ARC Centre of Excellence, Risk Frontiers are looking to couple their cat modelling infrastructure to downscaled climate change projections to model the impacts on a peril-by-peril basis for business.
A day after the IPCC report was published, the Royal Swedish Academy of Sciences awarded William Nordhaus and Paul Romer the Nobel Memorial prize for economics for their work on climate change and economic growth.
Since the 1970s, Prof. Nordhaus has been warning governments that their economic models were not properly taking into account the impact of global warming. Similarly, Prof. Romer developed the “endogenous growth theory”: the notion that countries can improve their underlying performance if they concentrate on supply-side measures such as research and development, innovation and skills. He argues that the creation and spread of ideas – whether that be around climate change or otherwise – is necessary for economic growth.
Understanding the economic costs of climate-related damages is essential to answering the question of how much society should be willing to pay to avert that damage (The Economist, 2018). Prof. Nordhaus’ work addresses this issue by modelling the economic harm of carbon emissions, thus allowing him to estimate the likely economic costs of the different IPCC Representative Concentration Pathways (RCPs).
Prof. Romer believes it is perfectly possible for global warming to be kept to a maximum of 1.5°C:
“Once we start to try to reduce carbon emissions, we’ll be surprised that it wasn’t as hard as we anticipated. The danger with very alarming forecasts is that it will make people feel apathetic and hopeless. One problem today is that people think protecting the environment will be so costly and so hard that they want to ignore the problem and pretend it doesn’t exist.”
The IPCC report is published at a time of international discord on climate mitigation, with most scientists acknowledging that the likelihood of achieving a plateau at the proposed 1.5 °C is very small. This is essentially a reflection on the myopic nature of global political institutions, and the opposing long-term nature of the problem at hand.
It also highlights the divisive nature of climate change in Australia. As elsewhere, it has become entangled with political agendas, class, energy and living standards. However, unlike elsewhere, adaptation to climate change has yet to occupy an ongoing, cross-party role in government policy as it has done, for example, in Europe. It has exposed an interesting divide between sectors that has come to the fore in recent years – with banking, insurance and industry at large leading the charge in understanding climate change risk and exposures. APRA, the Australian Prudential Regulation Authority, has ensured momentum here when in February 2017 Geoff Summerhayes declared climate change can no longer be considered a future financial risk:
“While climate risks have been broadly recognised, they have often been seen as a future problem or a non-financial problem. The key point I want to make today, and that APRA wants to be explicit about, is that this is no longer the case. Some climate risks are distinctly ‘financial’ in nature. Many of these risks are foreseeable, material and actionable now. Climate risks also have potential system-wide implications that APRA and other regulators here and abroad are paying much closer attention to.”
The bottom line
The global impasse on mitigation efforts only serves to highlight the importance of climate change adaptation planning and risk management in Australia. We’ll need to continue to adjust to the effects of climate change in the absence of addressing the underlying sources, but, ideally, we’d do both. If we believe the economics of the two most recent Nobel prize recipients, this may not be as costly as we think.
APRA (2017). Australia’s new horizon: climate change challenges and prudential risk. Geoff Summerhayes, Executive Member – Insurance Council of Australia Annual Forum, Sydney.
BBC News (2018). How Australia’s extreme heat might be here to stay. BBC News article by Adam Morton, Hobart, 13 January 2018.
IPCC (2018). The special report on global warming of 1.5°C: summary for policymakers.
The Economist (2018). The Nobel prize for economics is awarded for work on the climate and economic growth. Economist Business and Finance article, 8 October 2018.
Responses to the Lombok Earthquake, 2018 – Rapid Assessment Study
Jonathan van Leeuwen, Andrew Gissing and Ashley Avci
The recent earthquake that occurred in Lombok in August, 2018, presented an opportunity to study the responses of those affected in the immediate aftermath of the event. We find that tourists caught up in disasters are uniquely vulnerable. Few followed the encouraged actions of what to do in the event of an earthquake and most were reliant on local residents and tourist operators for advice. This article summarises the earthquake and how people responded and provides some reflections for policy makers.
The island of Lombok is located in the Nusa Tenggara Barat Region of Indonesia. It lies on the boundary between the Australian Plate and the Sunda Plate, which has produced numerous powerful earthquakes in the past. The region is a popular tourist destination, with rapidly increasing numbers of visitors since developed countries lifted travel warnings following the 2002 and 2005 Bali bombings and the SARS (severe acute respiratory syndrome) outbreak between 2002 and 2004. Tourism is a major source of income for Lombok and the neighbouring Bali and Gili Islands, with millions of visitors from around the world each year.
The August 5, 2018, Mw6.9 earthquake occurred as the result of shallow thrust faulting on or near the Flores Back Arc Thrust. The earthquake occurred in a subduction plate boundary region where the Sunda and Australia plates converge (USGS, 2018). In the region surrounding the location of the earthquake, there have been six other events of Mw6.5 or larger over the previous century. Four of these are likely to have occurred on the Back Arc Thrust system: a Mw6.5 in the Bali region to the west of Lombok in July 1976 and three events of Mw6.5, Mw6.5 and Mw6.6 in the Sumbawa region to the east of Lombok in November 2007 and November 2009. The Sumbawa earthquakes were associated with several deaths, hundreds of injuries and the destruction of hundreds of houses. This history of recent earthquakes means that locals would have been familiar with the impacts of damaging earthquakes.
The earthquake occurred at a depth of 31.0km, centred at the northern tip of Lombok. The local time was 7:46pm. It was preceded by a main foreshock on July 29, 2018 of Mw6.4, and numerous aftershocks including a Mw5.9 event on August 9, 2018 (USGS, 2018). The earthquake caused severe shaking in Lombok and surrounding islands, including Bali and the Gili Islands, and was felt as far as Sumbawa in the east (Cochrane, 2018) and Trenggalek Regency in the west (Solichah, 2018). Following the earthquake, tsunami warnings were issued: however, the maximum expected height was only half a metre and the warning was later cancelled.
Most of those affected by the earthquake were in North Lombok, East Lombok and Mataram City. Reports indicated that there were 392 fatalities, 1,353 injuries and damage to 67,875 houses, 606 schools, six bridges, three hospitals, ten health centres, 15 mosques, 50 prayer rooms and 20 office units (Badan Nasional Penanggulangan Bencana, 2018).
It is important for emergency managers to have an understanding of human behaviour during extreme events so that they can best develop their plans. In an effort to understand the behaviour of tourists and others following the earthquake, researchers from Risk Frontiers conducted a rapid assessment study utilising media analysis containing interviews with survivors. The method involved locating some 120 news articles sourced from a variety of online international, national and local media outlets. From these articles, interviews with 146 people who experienced the earthquake were extracted and analysed to identify damage that occurred and how people behaved during and after the earthquake.
A significant majority of interviewees were tourists (n=102), who conducted interviews with media outlets from their home countries either remotely or after returning home. Other interviews included local residents (n=20) and expats (n=9), with a further ten not stating where they were from.
At the time of the earthquake, interviewees were located on the island of Bali, approximately 50km to the east of Lombok (n=54); on Lombok (n=40); on the Gili Islands (n=28) and at other locations in the area (n=3). Twenty of those interviewed did not state where they had been at the time of the earthquake.
The interviewees came from a variety of nations, including Australia (n=38), Indonesia (n=25), Britain (n=23), Ireland (n=9), New Zealand (n=8), America (n=7), Singapore (n=5), France (n=4), South Africa (n=3), Canada (n=2), and one interviewee each from Africa (country unstated), Belgium, Denmark, the Netherlands, Malta, Pakistan and Spain. The age of interviewees was captured either by statement in the article or by approximation if a photo was available. Of those interviewed, 99 were categorised between 18 and 60 years old. Three were recorded as above 60 years old, and one was less than 18.
Most interviewees said they were with other adult/s when the earthquake occurred (n=51), or with both children and adult/s (n=24). Ten interviewees said they were with someone but didn’t specify their age/s and nine said they were alone.
In relation to their location at the time of the earthquake, interviewees stated that they were at a restaurant (n=29), in a hotel (size not stated) (n=14), at home and awake (n=9), in a single storey hotel (n=8), in a multi storey hotel (n=7), at home and asleep (n=3), in a shop or shopping centre (n=3), at the beach (n=2), on a footpath (n=2), in a car (n=1) or on a boat (n=1).
Consequences the interviewees observed from the earthquake included collapsed buildings (n=45), debris/objects falling (n=25), injuries (n=23), power cuts (n=22), loss of water from swimming pools (n=15), cracked walls (n=13), food shortages (n=11), deaths (n=11), water shortages (n=6), broken glass (n=4), downed cables (n=4), loss of sanitation (n=2), ground subsidence or uplift (n=1), flooding (n=1) and fires (n=1). Those located in Lombok and the Gili islands observed the most significant damage.
During the earthquake, interviewees most commonly reported, of their own behaviour, that they ran outside (n=43). Others reported that they dropped to the ground as they could not remain standing (n=5), sheltered under a table or bed (n=5), ran outside onto the beach (n=4), moved away from buildings (n=4), sheltered in doorways (n=3), deliberately dropped to the ground (n=2) or moved away from trees (n=2).
During the earthquake, interviewees observed others most commonly either running from buildings (n=44) or screaming (n=37). Other observed behaviours were crying (n=10), moving away from buildings (n=7), caring for others (n=4), running specifically to the beach (n=4), seeking shelter under tables or beds (n=3), holding onto objects or other people (n=3), panicking (n=3), seeking shelter under doorways (n=2), calling or messaging others (n=2) and dropping to the ground (n=1), reporting they could not stand.
Immediately after the earthquake, those interviewed moved to higher ground (fearing a tsunami) (n=29), sought advice on what to do from locals (n=9) or from hotel reception/staff (n=6), gave first aid to the injured (n=4), called or messaged someone (n=4), informed others of tsunami threat levels (n=3), climbed trees (fearing a tsunami) (n=3), searched for family member/s or friend/s (n=3), put on life jackets (fearing a tsunami) (n=2), assisted rescuing trapped person/s (n=2), were themselves incapacitated/requiring treatment (n=2) or extinguished fires (n=1).
Interviewees observed that immediately after the earthquake, others moved to higher ground (n=24), were screaming (n=12), panicking (n=11), caring for others (n=10), running (n=5), assisting the injured (n=5), crying (n=5), remaining on the beach (n=4), calling others (n=4), climbing trees (n=3), searching for others (n=3) or moving debris (n=1).
People said their actions immediately after the earthquake were directed by local residents (n=9), hotel staff (n=9), local authorities (n=3), other tourists (n=2) or by a minister of religion (n=1).
For those interviewees who said they contacted someone, contacts included their parent/s (n=8), other relative/s (n=3), friend/s (n=2), spouse/partner (n=2), children (n=1), authorities (n=1), neighbour/s (n=1) and a stranger (n=1). Six people contacted someone but did not specify who.
Many of those interviewed were not from countries which are associated with high earthquake risk. People’s previous experiences of earthquakes or education provided in their country of origin may have influenced some responses. This possibility is evidenced by the following responses:
“Everyone I spoke to just wants to get out but there’s not one free seat out of here today. About 90 per cent of us were westerners and we’re not trained for how to react in this situation.” (Interviewee from a country not prone to quakes) (Darvall and O’Shea, 2018).
“It’s scary when the ground is buckling under your feet. My partner and I were out of bed and under the table in a flash and we then immediately evacuated the house. When I was a child at school we had earthquake drills. Best training ever.” (Interviewee from a quake-prone country) (NZ Herald, 2018).
Descriptions of interviewees’ emotions during and immediately after the quake included feeling fearful (n=37), panicked (n=14), calm (n=9), concerned (n=7), upset (n=5), terrified (n=5), in shock (n=4), apathetic (n=2), surreal (n=2), and other (n=6). Some 83 interviewees did not state their emotions during and immediately after the quake.
Interviewees said they obtained information about tsunami risk from local residents (n=9), the internet (n=6), warning sirens (or the lack thereof) (n=4), social media (n=3), hotel staff (n=2), calling family or friends at home (n=2), other tourists (n=2), local authorities (n=2), observing the ocean (n=2) or overhearing other people (n=2).
Over subsequent days, a significant number of people said they evacuated soon after (n=29). Some stayed to assist rescue, medical or relief efforts (n=11), although these were mainly locals and expats.
The evacuation of tourists from the Gili Islands was said to be chaotic due to the combination of the lack of capacity to evacuate tourists and the fearful state of tourists and locals. There were reports of long waits, pushing and shoving and passage being offered to the highest bidders. Those interviewees who experienced the evacuation described it as:
“People were just throwing their suitcases on board and I had to struggle to get my husband on, because he was bleeding.” (Embury-Dennis, 2018).
“We just witnessed one of the boats get completely overfilled with tourists climbing on, with the officials trying to keep them back off the boat, pushing them and shoving them. That boat still hasn’t left yet.” (ABC News, 2018).
“People are punching and hitting each other.” (Osborne, 2018).
Discussion and conclusion
Many tourist destinations both within Australia and abroad are susceptible to a range of natural hazard risks. For example, some 26 Australians lost their lives during the Asian tsunami in 2004.
Often, many of the elements that make locations aesthetically appealing to tourists are associated with natural hazard risk. For example, warm, shallow seas and sandy islands make idyllic tropical resort getaways, but these places are often at risk from severe weather, while scenic mountain vistas are often the product of tectonic activity which causes earthquakes and volcanism.
Tourists are uniquely vulnerable. Tourists may be unaware of risks present at their destination, lack local support networks and encounter cultural and communication barriers. Research has previously shown that tourists behave differently to locals. During evacuations they tend not to shelter with family and friends, but seek shelter at public evacuation centres, simply return home or find another hotel (Drabek, 1999). Observations from the Lombok disaster support such conclusions: in particular, that many tourists simply leave soon after a disaster and are reliant on locals for direction.
Many of those interviewed ran from buildings or observed others running from buildings. This behaviour is in conflict with actions encouraged by international and local authorities, which promote the actions of drop, cover and hold.
Counter to some research that suggests that people do not panic in the aftermath of disasters (Lorenz et al. 2018), observations from this event show that panic and chaos can occur. This suggests that in more extreme and less predictable events, panic and chaos is likely or that tourists are more likely to panic. Such questions require further exploration.
Promotion of disaster risk by travel agents and tourism operators conflicts with wider tourism promotion. The Australian Department of Foreign Affairs does provide some details about natural hazard risk on its Smartraveller website, although more needs to be done than passively informing travellers. There could be an opportunity to engage with the medical profession and travel health clinics to promote natural hazard risk and safety behaviours at the time travellers seek travel health advice.
Finally, tourists in Australia are not immune from the impacts of natural hazards, as illustrated by the impacts of Cyclone Debbie in the Whitsunday Region. It is important that tourism operators are engaged regarding disaster preparedness and connected with disaster management structures.
ABC News (2018). Witness describes chaos when earthquake hit the Gili Islands. ABC News. 7 August 2018. [Accessed 8 Oct. 2018].
Cochrane, J. (2018) Powerful Indonesia earthquake kills at least 82. The New York Times. 5 August 2018. [Accessed 10 Oct. 2018].
Darvall, K and O’Shea, M. (2018). ”I just want to get off the island now”: Bondi restaurant owner shares terrifying evacuation footage after earthquake hit Lombok while he was holidaying with his girlfriend. Daily Mail Australia. 6 August 2018. [Accessed 8 Oct 2018].
Drabek, T.E. (1999). Disaster evacuation responses by tourists and other types of transients. International Journal of Public Administrations, 22(5), pp.665-677.
Embury-Dennis, T. (2018). Lombok earthquake: tourists “forced to pay to board rescue ships”. The Independent. 6 August 2018. [Accessed 8 Oct. 2018].
Lorenz, D.F., Schulze, K. and Voss, M., (2018) Emerging citizen responses to disasters in Germany. Disaster myths as an impediment for a collaboration of unaffiliated responders and professional rescue forces. Journal of Contingencies and Crisis Management, 26 (3), pp.358-367.
Osborne, S. (2018). Lombok earthquake latest: tourists flee Indonesian island after powerful magnitude-7 quake kills at least 98. The Independent. 6 August 2018. [Accessed 8 Oct. 2018].
Solichah, Z. (2018). Warga Jember dan Banuwangi rasakan gempa Lombok. Antara News. 5 August 2018. [Accessed 10 Oct. 2018].
A second earthquake with magnitude larger than 5 occurred today (November 9, 2018) near Lake Muir in southwestern Western Australia, and Geoscience Australia assigned it a magnitude of 5.4. This earthquake, shown by the large red dot in Figure 1, occurred about 10 km southeast of the magnitude 5.7 earthquake that occurred on 17 September 2018. The aftershocks of today’s earthquake, shown by small red dots in Figure 1, are located at the southern end of the aftershock zone of the September 17 event, shown by the yellow dots. Today’s earthquake was preceded by a series of foreshocks that occurred overnight, and was felt between Albany and Perth. The shaking intensities of the two earthquakes are shown in Figures 2 and 3.
The orientation of the fault plane on which the 17 September earthquake occurred is shown on a Wulf net projection in Figure 4. This shows that the earthquake had a thrust mechanism on a fault plane striking east-northeast. The InSAR (interferometric Synthetic Aperture Radar) map in Figure 5 shows that the west side moved up and the east side moved down on a plane dipping down to the west-northwest. The change in elevation along this dip direction is shown at the upper left of Figure 5.
The two earthquakes are shown by the yellow stars on a map of historical earthquake epicentres in the Southwest Western Australia Seismic Zone (SWWASZ) in Figure 6. The contours show annual probability of events of magnitude 5 and above from QuakeAUS6. The two earthquakes occurred on the southwestern edge of the SWWASZ.
As described in our Briefing Note 373, we have recently released our new probabilistic earthquake loss model for Australia, QuakeAUS 6.0. The updated model, developed by Dr Valentina Koschatzky with input from Risk Frontiers’ Chief Geoscientist, Dr Paul Somerville, incorporates Geoscience Australia’s recent revision of the Australian Earthquake Catalogue (Allen et al., 2017), which has more than halved the rate of earthquakes exceeding 4.5 in magnitude. The main features of the new model are:
New Distributed Earthquake Source Model (based on RF analysis of the new GA catalogue – 2018)
Inclusion of an Active Fault Model
Updated Soil Classification (McPherson 2017)
Updated Soil Amplification Model (Campbell & Bozorgnia 2014)
After the Christchurch earthquake sequence we are very aware of liquefaction and the large scale damage it was responsible for. It may come as a surprise to learn that liquefaction is a big safety issue for the shipping industry where it is sometimes called dry cargo liquefaction or dynamic separation. The article below was written by Susan Gourvenec a professor of offshore geotechnical engineering at the University of Southampton. It was printed in Ars Technica, a website covering news and opinions in technology, science, politics, and society. It publishes news, reviews, and guides on issues such as computer hardware and software, science, technology policy, and video games.
A lot is known about the physics of the liquefaction, yet it’s still causing ships to sink.
Think of a dangerous cargo, and toxic waste or explosives might come to mind. But granular cargoes such as crushed ore and mineral sands are responsible for the loss of numerous ships every year. On average, 10 “solid bulk cargo” carriers have been lost at sea each year for the last decade.
Solid bulk cargoes – defined as granular materials loaded directly into a ship’s hold – can suddenly turn from a solid state into a liquid state, a process known as liquefaction. And this can be disastrous for any ship carrying them – and its crew.
In 2015, the 56,000-tonne bulk carrier Bulk Jupiter rapidly sank around 300km south-west of Vietnam, with only one of its 19 crew surviving. This prompted warnings from the International Maritime Organization about the possible liquefaction of the relatively new solid bulk cargo bauxite (an aluminum ore).
A lot is known about the physics of the liquefaction of granular materials from geotechnical and earthquake engineering. The vigorous shaking of the Earth causes pressure in the ground water to increase to such a level that the soil “liquefies.” Yet despite our understanding of this phenomenon (and the guidelines in place to prevent it occurring), it is still causing ships to sink and take their crew with them.
Solid bulk cargoes
Solid bulk cargoes are typically “two-phase” materials, as they contain water between the solid particles. When the particles can touch, the friction between them makes the material act like a solid (even though there is liquid present). But when the water pressure rises, these inter-particle forces reduce and the strength of the material decreases. When the friction is reduced to zero, the material acts like a liquid (even though the solid particles are still present).
A solid bulk cargo that is apparently stable on the quayside can liquefy because pressures in the water between the particles build up as it is loaded onto the ship. This is especially likely if, as is common practice, the cargo is loaded with a conveyor belt from the quayside into the hold, which can involve a fall of significant height. The vibration and motion of the ship from the engine and the sea during the voyage can also increase the water pressure and lead to liquefaction of the cargo.
When a solid bulk cargo liquefies, it can shift or slosh inside a ship’s hold, making the vessel less stable. A liquefied cargo can shift completely to one side of the hold. If it regains its strength and reverts to a solid state, the cargo will remain in the shifted position and cause the ship to permanently tilt (or “list”) in the water. The cargo can then liquefy again and shift further, increasing the angle of list.
At some point, the angle of list becomes so great that water enters the hull through the hatch covers, or the vessel is no longer stable enough to recover from the rolling motion caused by the waves. Water can also move from within the cargo to its surface as a result of liquefaction and subsequent sloshing of this free water can further impact the vessel’s stability. Unless the sloshing can be stopped, the ship is in danger of sinking.
The International Maritime Organization has codes governing how much moisture is allowed in solid bulk cargo in order to prevent liquefaction. So why does it still happen?
The technical answer is that the existing guidance on stowing and shipping solid bulk cargoes is too simplistic. Liquefaction potential depends not just on how much moisture is in a bulk cargo but also other material characteristics, such as the particle size distribution, the ratio of the volume of solid particles to water and the relative density of the cargo, as well as the method of loading and the motions of the vessel during the voyage.
The production and transport of new materials, such as bauxite, and increased processing of traditional ores before they are transported, means more cargo is being carried whose material behavior is not well understood. This increases the risk of cargo liquefaction.
Commercial agendas also play a role. For example, pressure to load vessels quickly leads to more hard loading even though it risks raising the water pressure in the cargoes. And pressure to deliver the same tonnage of cargo as was loaded may discourage the crew of the vessel draining cargoes during the voyage.
What’s the solution?
To tackle these problems, the shipping industry needs to better understand the material behavior of solid bulk cargoes now being transported and prescribe appropriate testing. New technology could help. Sensors in a ship’s hold could monitor the water pressure of the bulk cargo. Or the surface of the cargo could be monitored, for example using lasers, to identify any changes in its position.
The challenge is developing a technology that is cheap enough, quick to install and robust enough to survive loading and unloading of the cargo. If these challenges can be overcome, combining data on the water pressure and movement of the cargo with information on the weather and the ship’s movements could produce a real-time warning of whether the cargo is about to liquefy.
The crew could then act to prevent the water pressure in the cargo rising too much, for example, by draining water from the cargo holds (to reduce water pressure) or changing the vessel’s course to avoid particularly bad weather (to reduce ship motions). Or if those options are not possible, the crew could evacuate the vessel. In this way, this phenomenon of solid bulk cargo liquefaction could be overcome, and fewer ships and crew would be lost at sea.
Susan Gourvenec is a professor of offshore geotechnical engineering at the University of Southampton. This article was originally published on The Conversation and has been lightly edited to conform to Ars Technica style guidelines. Read the original article.
Macquarie University’s Lighthouse publication recently showcased research being undertaken by Risk Frontiers’ Andrew Gissing on planning and capability requirements for catastrophic events. This research, undertaken through the Bushfire and Natural Hazards Cooperative Research Centre, is investigating better practice approaches to planning and preparedness for extreme events that may overwhelm existing response frameworks. You can read the story highlighting the research in the context of the recent Sulawesi earthquake and tsunami here: https://lighthouse.mq.edu.au/article/october/sulawesis-earthquake-and-tsunami-provide-key-insights-into-catastrophe-response
Twenty-eight years on from the First Assessment Report in 1990, the IPCC’s most recent Special Report on Global Warming delivers an urgent warning to policymakers that we are reaching the point of no return for mitigating anthropogenic impacts on global warming and associated climate change. The report has divided opinion in Australia and further highlights the polarising power of climate change across government, academia and industry.
The report finds that limiting global warming to 1.5 °C, although “possible within the laws of chemistry and physics”, would now require rapid and unprecedented change in all aspects of society. Global net human-caused emissions of CO2 would need to fall by approximately 45 percent from 2010 levels by 2030, reaching ‘net zero’ around 2050. This means that any remaining emissions would need to be balanced by utilising as-yet under-developed technologies to remove CO2 from the air.
The report also highlights that we are already seeing the consequences of 1 °C of global warming through more extreme weather, rising sea levels and diminishing Arctic sea ice. One of the difficulties in communicating the impacts of seemingly small increases in mean temperatures is related to how this affects extreme weather events. The immediate reaction of many to “a 1 °C temperature increase” is to imagine oneself lying on a beach at 24 °C and then at 25 °C with global warming. Not that bad, right?
The key notion is that a small increase in the mean temperature also shifts the tails of the distribution, meaning the probability of extreme weather events increases just as much – and sometime more (depending on the shape of the distribution) – as the shift in the mean temperature (Figure 1). Prof Andy Pittman, the director of the ARC Centre of Excellence for Climate Extremes at the University of New South Wales, describes this nicely in an anecdote to BBC News back in January:
“the probability works a bit like if you stand at sea level and throw a ball in the air, and then gradually make your way up a mountain and throw the ball in the air again. The chances of the ball going higher increases dramatically. That’s what we’re doing with temperature.”
Figure 1 Small changes in the averages of many key climate variables can correspond to large changes in weather. Source: Solomon et al. (2007).
What the report says
Abridged findings from the report that have high confidence (80 % chance) are:
Global warming is likely to reach 1.5 °C between 2030 and 2052 if temperatures continue to increase at the current rate (Figure 2);
There are robust differences in climate model projections of regional climate characteristics between present-day and global warming of 1.5 °C and between 1.5 °C and 2 °C, most notably sea level rise and extreme heat;
Most climate change adaptation needs will be lower for global warming of 1.5 °C compared to 2 °C;
Estimates of the global emissions outcomes of current nationally stated mitigation ambitions as per the Paris Agreement would not limit warming to 1.5 °C, even if supplemented by challenging emissions reductions after 2030.
Figure 2 Observed monthly global mean surface temperature change and likely modelled responses to anthropogenic emission and forcing pathways relative to the 1.5 ° C threshold, extending to 2.0 ° C. Source: Figure SPM.1 in IPCC (2018).
The report advocates for anthropogenic climate change to be limited to 1.5 °C, and cites considerable additional impacts for land, energy, industry, buildings and transport in a “2° C world”. The marine world is singled out for particular impacts under a 2° C scenario, with modelling and observations suggesting the large-scale die-out of tropical coral reefs including, of course, the Great Barrier Reef (GBR).
Changes to the GBR not only have direct impacts for marine biodiversity, but also for cyclone risk along the adjacent mainland coast, which would potentially experience higher storm surge and wave exposure under a combination of rising sea levels and reduced energy dissipation by coral reefs.
The report is published at a time of international discord on climate mitigation, with most scientists acknowledging that the likelihood of achieving a plateau at the proposed 1.5 °C is very small. This is essentially a reflection on the myopic nature of global political institutions, and the opposing long-term nature of the problem at hand.
It also highlights the divisive nature of climate change in Australia. As elsewhere, it has become entangled with political agendas, class, energy and living standards. However, unlike elsewhere, adaptation to climate change has yet to occupy a central role in government policy as it has done, for example, in Europe. It has exposed an interesting divide between sectors that have come to the fore in recent years – with banking, insurance and industry at large leading the charge in understanding climate change risk and exposures, and the federal government lagging.
The righteous indignation of some in the public eye too often overshadows the high standards of objectivity, self-imposed on the science community, in delivering the most robust findings possible. This was highlighted last week by the coincidental media release of an ‘audit’ of climate data used by climate models, undertaken as part of a PhD at James Cook University, with the apparent intention of undermining the IPCC’s report.
The audit claims that the underlying data used by Global Climate Models (GCM) is unfit for purpose, citing concerns around temperature anomalies, coverage and sample size, and that GCM predictions cannot be relied on as a result.
While the audit was undertaken as part of a high-quality PhD thesis (McLean, 2017), it is as yet unpublished in the peer-reviewed scientific literature. The concerns over observational data coverage and sample size in years prior to the satellite era are well known and this is why climate reanalysis data should be handled with care – particularly in the Southern Hemisphere.
The assertion that a limited number of spurious temperature anomalies in observational records would distort the global suite of ensemble climate model output is difficult to prove, given the strict uncertainty estimates and sampling checks climate institutions such as the Bureau of Meteorology and the UK Met Office undertake. However, it is still important that end-users understand the multiple layers of uncertainty inherent in climate modelling.
By comparison, the IPCC’s report included the contributions of 91 climate experts from 40 different countries and draws on over 6,000 cited references. The simultaneous reporting of both the climate audit and the IPCC report in the media gives equal weighting to the two and undermines the climate science, at an important juncture for climate politics internationally.
The global impasse on mitigation efforts only serves to highlight the importance of climate change adaptation planning and risk management in Australia, as we transition to a period in which we look to accommodate climate change impacts rather than reduce them, or indeed to utilize a combination of the two.
It also suggests (fascinatingly, from a data science perspective) that, as anthropogenic warming proceeds, we may no longer be able to apply the near-past to predict near-future climate risk as relationships between climate variables in the short-term past become no longer valid.
McLean, J.D. (2017) An audit of uncertainties in the HadCRUT4 temperature anomaly dataset plus the investigation of three other contemporary climate issues. PhD thesis, James Cook University, available https://researchonline.jcu.edu.au/52041/.
Solomon, S., et al. (2007) Technical Summary. In: Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA.