Sciences & Technology
How we can link some extreme weather to climate change
As floods, heatwaves and droughts increase, how will they affect our lives and bring about change
Published 11 April 2017
Extreme is the new normal when it comes to weather, with devastation caused by floods, fires and cyclones filling our news feeds all too frequently.
Thanks to the relatively recent development of event attribution in climate science, researchers can now confidently attribute the increase in extreme weather events to human-forced climate change.
For Australians, climate change means more heatwaves, more droughts, more intense cyclones (although less of them) and more flooding. The impact of such weather is already a reality for many who have lost homes and, tragically, loved ones, in events like the recent Queensland and northern New South Wales floods.
But the impact of extreme weather will be felt more widely. How will it affect our health? Are our buildings changing to adapt? Will our insurance policies change?
We asked seven University of Melbourne experts about our preparedness.
The impacts of climate change are a significant threat to human health, and our systems are not yet prepared to deal with them.
Professor Doherty says:
Make no mistake, climate change is the greatest long-term threat to human health.
Heat stress, extreme cold, diminished food and fresh water availability, human conflict and mosquito and water-borne infections loom as the biggest dangers of a warmer world.
Sciences & Technology
How we can link some extreme weather to climate change
Extreme heat kills and very recently we’ve seen intense heatwaves in India, Pakistan, Iran and Middle Eastern countries. A further potential threat is cold stress due to the slowing of the Atlantic Conveyer, the Gulf Stream that keeps the west coast of Britain and east coast of America warm. That could make a London winter seem more like Moscow.
Then there’s flooding. Extreme rainfall events lead to flooding, a breakdown of the sewerage systems and the greater likelihood of sewage contamination and infections.
With rising sea levels and more flooding events, come water-borne infections, like typhoid and cholera. Mosquito-borne infections will move further away from the equator. We can expect to see malaria in northern Australia and a lot more dengue coming further south. We might see Japanese encephalitis.
But the biggest threat may be to food production with resultant social disruption and conflict. We’ve already seen how drought and fires in Russia led to a failed wheat harvest, massive increases in bread prices and social upheaval in Egypt. Drought is also considered to have been a key trigger of the current situation in Syria.
Revolutions and wars happen when people do not get enough to eat. Lack of food, fresh water and living space may ultimately be the greatest hazard for social stability and human health.
Associate Professor Blashki says:
In my opinion we are not adequately prepared for the health impacts of climate change. When you look at how Melbourne’s health service was stretched in the 2009 heatwave, it’s evident that a lot more preparations could be in place, especially as such events are predicted to become more frequent and severe in coming decades.
Environment
A long climatic affair
As a priority we need to build surge capacity so ambulance and hospital services can react quickly during extreme weather events.
We ought not forget the importance of strengthening mental health systems in the aftermath of extreme weather events - the profound mental health impacts after an extreme event don’t always get the attention they deserve.
And we should not forget the important role of GPs who are the front-line health service in the community and if adequately prepared can really step up during extreme events to meet surge requirements.
As the future medical workforce, our university students could definitely have more curriculum on the health impacts of climate change, which is likely to be relevant during their working careers.
Professor Doherty AC is Head of the Department of Microbiology and Immunology at the University of Melbourne and Patron, Doherty Institute for Immunity and Infection.
Associate Professor Blashki is from the Nossal Institute for Global Health at the University of Melbourne and Co-founder of Doctors for the Environment.
Extreme weather is already affecting Australian farming and, while some are responding strategically, the industry needs improved risk management strategies to manage the threat better.
Australian farmers are skilled at operating in and responding to a highly variable climate. But, to date, on-farm adaptations to the climate have mainly been incremental, which succeeds in the face of gradual change but is unlikely to prove tenable in the face of increased extreme weather events.
In the summer of 2016, a record-breaking two-day extreme heat event in the NSW Shoalhaven region resulted in the loss of 40 dairy cows. Such events are set to become the norm sooner rather than later, so on-farm preparedness should be part of usual practice. Livestock and the horticulture and viticulture industries are particularly vulnerable to extreme heat.
Environment
Climate change: What it means for fruits
The sensitivity to different extreme events, like flood, drought, wind, frost and bushfires is evident across all agricultural industries (the recent flooding in Queensland and NSW will have large financial impacts on farmers, processors, retailers and consumers).
Farmers need a range of risk management options to manage them, including access to an improved forecasting system, practical and proven on-farm measures to mitigate the magnitude of an extreme event, and, pre-, intra- and post- event risk management scenarios.
‘First movers’ in the agricultural sphere are already responding to climatic changes. One such example is the wine-maker, Brown Brothers. Water shortages, earlier and more compressed vintages, higher alcohol content, heat effects on wine colour, increasing sunburn, decreased grape acidity, and fruit losses due to smoke taint from bushfire events contributed to their acceptance that a fundamental shift in the climate was occurring.
Consequently from 2008 the company included planning for climate change into their business strategy. Within two years, Brown Brothers had expanded their portfolio of five vineyards across Victoria to include 400 hectares of vineyards, a winery and some brands in Tasmania. Now others are looking to make similar moves, but land prices have already responded in anticipation, while others still deny anything has changed.
Dr Ann-Maree Graham and Professor Eckard are from the Faculty of Veterinary and Agricultural Sciences at the University of Melbourne and the Primary Industries Climate Challenges Centre.
Existing Australian buildings are poorly equipped to deal with current weather, let alone future extreme events. In particular, we need to change our use of glazing to manage the increased risk of heatwaves.
Australia is a hot, dry continent and an increase in heatwaves is a key climate change issue our buildings need to adapt to – glazing and shading are critical.
Our existing stock is characterised by a lack of insulation, leaky construction and substandard glazing, all of which put greater demand on air conditioning and occupant comfort.
The over-use of glass is a particular problem – if you look at Melbourne CBD buildings post the introduction of the modern curtain wall, many are all glass. Glass is very poor at reducing heat transfer and is the only building material that admits solar radiation, heating up interior spaces and making any window without shading a demand on air conditioning.
Using less glass is an eternally unpopular solution with designers and occupants, so we need to look to the higher performing products, where Australia still lags behind other countries. Whilst Australian buildings still feature either single or double glazing, most European countries use double, or triple glazed windows.
There are, of course, other extreme weather events like flooding and cyclones that we need to prepare for, both already addressed by existing regulations.
Although sea level rise does not classify as an extreme weather event, it is currently in focus across Australia, as councils work to determine appropriate responses to projected rises, storm surge and inundation.
Chris Jensen is from the Faculty of Architecture, Building and Planning at the University of Melbourne.
Properties in areas at high-risk of extreme weather such as flooding will necessarily incur a higher premium, so more disaster mitigation strategies are needed to keep insurance policies feasible for insurers and their customers.
The recent floods of March 2017 in northern New South Wales and North East and South East Queensland, in the wake of Cyclone Debbie, rank as major floods with the level of damage expected to be of the magnitude of hundreds of millions of dollars, potentially exceeding one billion dollars. For example, Insurance Australia Group estimates it will incur a net natural peril claims cost of approximately $140 million from Tropical Cyclone Debbie and according to the Insurance Council of Australia, as of midday 4th April, insurers have received $306 million in claims from about 28,000 claimants, which is expected to rise further.
Historically, extreme rainfall events and flooding have always featured in Australia’s weather patterns, evidenced by the observations of the pioneer John Oxley in 1824 and records of river gauge readings since. For example, the river gauge at the Brisbane River at the Port Office recorded its highest ever level on 14th January 1841 and its second highest on 5th February 1893. The Queensland floods of January 2011 ranked sixth among recorded events at this location, culminating in about $1 billion in damage.
To mitigate the impact of floods, be it loss of life or property, early warning systems and emergency response procedures have been developed by the Bureau of Meteorology in tandem with local authorities and building standards have been improved. Additionally, in response to the 2011 floods, insurers now provide flood cover so that insured people in flood-prone areas can recuperate financial losses in such catastrophic events. Risk rating by insurers of insured properties means that properties at high risk of flooding will incur higher premiums. Therefore, it is imperative that more disaster mitigation strategies are implemented so that insurance policies are feasible for insurers and their customers.
As it currently stands, insurers have graded the New South Wales and Queensland flood events as catastrophic and therefore have prioritised claims assessments so that insured parties are at least compensated in a timely manner and can resume normal lives as soon as possible. It is in such times that the insurance industry demonstrates its benefits to the public and as being essential to Australia’s economy.
Kevin Fergusson is from the Faculty of Business and Economics at the University of Melbourne.
Fire management agencies already manage risk well, but individuals living in high-risk areas need to be better prepared, as many homes have been built there without adequate protection.
Bushfire frequency and intensity is likely to change under future climates. Some areas are likely to have more fires, while others may have less. Regardless, communities need to be prepared for both the current and future risk of loss from fires.
Fire management agencies already undertake management actions that attempt to reduce future fire risk. These include fuel treatments, community engagement, training and investment in fire-fighting resources like trucks and helicopters.
So there is limited scope for agencies to alter management practices to significantly reduce fire risk to communities without compromising environmental values in the landscape.
Urban planning decisions have the greatest potential to alter fire risk under changing climates. Historic planning decisions in cities have resulted in a complex urban interface with an extremely high fire risk. Many of these houses were built without consideration for fire and are not resilient to fire. Some commentators have proposed buy back schemes for the worst areas, but these are likely to be extremely costly and have little community support. We must live with these mistakes and endeavour not to repeat them in the future. Current and future developments are required to consider fire risk, but the adequacy of the standards have not yet been fully tested.
Communities and individuals in fire prone areas must therefore accept the responsibility of preparing themselves adequately for fire. Unfortunately, research results suggest that few residents are undertaking adequate preparation and thereby increasing the risk to their property and themselves.
Now and in the future we need to work with communities to ensure that residents understand their exposure to fire and develop emergency plans that can prevent or minimise the loss of life during fires in the future.
Dr Penman is from the Faculty of Science at the University of Melbourne.
Banner image: Flood waters enter in the parking lot outside the Robina Hospital on the Gold Coast in south-east Queensland following cyclone Debbie, on March 30, 2017. Picture: Getty Images
We acknowledge Aboriginal and Torres Strait Islander people as the Traditional Owners of the unceded lands on which we work, learn and live. We pay respect to Elders past, present and future, and acknowledge the importance of Indigenous knowledge in the Academy.
Read about our Indigenous priorities