The Governor’s Environmental Science Public Lecture

by Kate Bongiovanni
RSV Science Communication Officer

This article follows a presentation to guests of the Governor of Victoria on 11 September 2019, featuring Dr Pandora Hope from the Bureau of Meteorology, Professor Roslyn Gleadow and Professor Nigel Tapper from Monash University, and Professor Richard Eckard and Associate Professor Anthony Boxshall from the University of Melbourne.

Set in the exquisite ballroom of Government House, around 500 guests were awestruck from the moment they arrived. The ballroom has had varied uses over the years – hosting 19^th century balls for 2000 people, providing a temporary classroom for the early days of Mac.Robertson Girls’ High School, and more recently the acrobatic performances of Circus Oz. On the evening of 11 September, the magnificent ballroom played host to a discussion on contemporary environmental science, featuring a globally-significant panel of Victorian scientists.

Official proceedings began with an introductory speech from Her Excellency the Governor, Linda Dessau. The Governor framed how we had come together under the banner of science to share methodologies and contemporary innovations, emphasising the need to learn more about science, how it shapes our environment and the important role of scientists in informing decisions about our future. The theme for the evening was how scientists can help us all adapt to Victoria’s “new normal” – a warmer, drier climate.

Our MC was Associate Professor Anthony Boxshall MRSV, an Enterprise Fellow at the University of Melbourne and the Principal of Science into Action. Anthony set the context: our climate is already changing. Under the Paris Agreement, Australia and the world’s great nations have committed to reducing global temperatures to a 1.5-2°C rise over pre-industrial levels. Should this exercise prove successful, a 2°C rise will still have far-reaching climate effects, with major implications for the State of Victoria.  He explained how the dramatic changes in climate we are currently experiencing have sparked research on how we can adapt and adjust to an emerging, new climate “normal.” The senior scientists gathered from different institutions and sectors were briefed on helping us to understand how we could approach this challenge from a variety of angles.

The panel aimed to showcase some of the work in climate adaptation produced by Victorian scientists and, most importantly, share actions we could all take in our personal and professional lives.

Climatologist Dr Pandora Hope is a Principal Research Scientist with the Bureau of Meteorology. She set the scene by showing the shift in global temperature averages from 1910 to today, and also modelled projections of future temperatures until 2100.  Pandora presented a graph which displayed the long term zero-line average temperature. She explained that since the 2000s our climate has been almost always above the zero-line, although there are still some isolated cold periods. In this time, we have experienced the warmest year on record, 2013.  However, 2019 could be set to change this picture, as 2018-2019 was a record-breaking summer.

Pandora noted that temperature is not the only variable which responds to climate change.  Rainfall changes are also becoming the new climate norm. We are experiencing new extremes such as more frequent droughts, which have significant effects on plants and animals. Additionally, there are seasonal changes characterised by reduced rainfall in winter and spring, and a slight rise in storm intensity in summer. Industry and city planners are already responding to these changes.

Agricultural scientist Professor Richard Eckhart followed on from Pandora, shedding light on how these climatic changes are affecting the agricultural industry. As the Director of the University of Melbourne’s Primary Industries Climate Challenges Centre, he is uniquely placed to explain how some sectors are having to relocate further south because of climatic changes. Inland areas in central and northern Victoria are experiencing increased temperatures during extreme events and high variability in rainfall. Several industries, such as grain, cotton, dairy, wine and fruit, are challenged by these climatic changes.  The southern coast of Victoria, moderated by the ocean, has milder temperatures and more reliable rainfall, offering more suitable conditions for these industries to make a transition.

In order to adapt to warmer climate, the dairy industry has introduced innovations in irrigation systems and the introduction of livestock insulation to protect cattle from the harsher elements. Hotter weather is pushing the dairy industry southward to places such as Gippsland and Tasmania.

The wine industry is also undergoing transformations. Some major pinot noir vineyards have already made the move south to Tasmania, while others have changed the varieties of grapes grown in Victorian vineyards. Researchers are looking into replacing wines traditionally grown in Victoria with grape varieties from Southern Italy that are acclimatised for Mediterranean conditions.

The Goulburn Valley Fruit industry may soon need to relocate south, due to a lack of a sufficient cold period in winter. The growth of winter fruits, such as apples and pears, is reliant on a sustained chill from winter lows.  If these lows are no longer reached, the winter fruit industry will need to relocate.

To minimise disruption to our agricultural sector, we need to move towards low emission carbon farming. Carbon farming involves growing more trees, promoting healthier soils and avoiding greenhouse gas emissions from the cultivation of crops and raising of animals. Sequestering carbon in plants and soils while minimising carbon emissions is a desirable function from agriculture, returning benefits to the whole planet – it is anticipated this will become an industry in its own right as we come to terms with what is required to manage the global climate.

Professor Ros Gleadow MRSV is a biologist at Monash University, specialising in plant physiology. Ros elaborated on Richard’s points with a focus on plant adaptions to climate change.

The Earth has some ancient forests with trees that are hundreds of years old. These trees were produced under a different climate and their seedlings will no longer be suitable for our warmer climate. To overcome this obstacle in a natural way, parks need to incorporate different climatic zones; for example, both high and low elevation areas. In this way, seeds can be moved naturally (by wind and animals) to different elevations where they might demonstrate more success and adaptation across generations. To find out what kinds of plants are suitable for different environments and a new climate, Ros recommends consulting websites like “Which Plant Where?”.

Higher carbon dioxide concentrations in our atmosphere means plants are more efficient at photosynthesis (converting sunlight, carbon dioxide and water into sugar and oxygen). However, this high efficiency comes at the cost of a lower production of protein. The consequence of this reduction in leaf protein is that animals, such as koalas, need to either eat more leaves or change the type of leaves they eat in order to meet their nutritional needs. This problem needs to be addressed quickly, as some leaf varieties could return a third less protein in the next fifty years.

There are implications for human diets as well. For example, the same process will affect protein in wheat grains and, consequently the quality of the flour produced and its baking performance. Research is being conducted to create varieties of wheat that are most resilient to carbon dioxide.  This process can take up to 15 years.

Another key human staple affected by climate change is the cassava plant, native to South America. Cassava is a carbohydrate-rich root vegetable that produces small amounts of cyanide, dependent on environmental conditions. Intensified drought results in higher cyanide concentrations, thus more toxicity. However, Ros emphasised there are steps we can take to adapt and make cassava safe.  For instance, adding a bit of water to the crop just before harvesting reduces toxicity. Yet this can be difficult in many communities dependent on cassava with limited access to water. An alternative is to crush up the cassava and mix in a small amount of water before consuming, which allows the cyanide to safely dissipate. New organisations are working to provide important education to locals to prevent risks from climate-driven physiological changes to cassava plants.

More people die of extreme heat than any other natural hazard, including fires and cyclones. Heat related deaths occur mostly in urban centres. When average daily temperatures surpass 30°C, there is a 17% spike in heat related deaths. There is a high possibility of increasing the death toll with more extreme summers.

Professor Nigel Tapper uncovered human health impacts and adaptions in the urban environment. Nigel is a Professor of Environmental Science at Monash University, leading a research group on Urban Climates that seeks to reduce heat wave mortality rates. Factors such as age, health, ethnicity, socio-economic status as well as tree cover in a given postcode affect the probability of heat mortality. The group aims to improve public heat health warnings and ensure the emergency services are better prepared.

Urban heat maps are used to identify and then target areas for cooling interventions and better heatwave preparedness. Through working with municipal agencies and the state government, this approach has resulted in a 50% drop in heat mortality in Melbourne in the last ten years.

Reducing heat in cities is not only necessary for human health but also to help protect infrastructure like roads, train lines, power lines and communications. It is possible to create a cooling of 2°C on days of peak temperatures. In the built environment, simple steps such as changing the colour of roof tiles from dark (low reflectivity) to light colours (high reflectivity) enhances the Earth’s natural albedo effect (reflecting solar radiation back into space) and has a big impact on urban cooling.

Increasing tree cover is another way to reduce heat in urban centres.  Trees evapotranspire, which means they return water to the atmosphere and cool the air, much like how an evaporative cooling system works in your home. This means leaf temperatures are rarely above 28°C, making trees much more effective than a shade cloth on hot days. City councils are working on which trees are more suitable for different areas, depending on the anticipated conditions under a new climate regime.  Most large cities around the world are increasing their tree cover. This process takes years to decades to establish, and must begin without delay to secure the desired outcomes for Victoria’s urban areas.

Further innovation involves harvesting storm water to support green infrastructure (green walls, green roofs, nature strips and swales), which further cools the urban environment, mitigates flooding from heavier rainfall and assists with cleaning the air of particulate pollution.

To end the night’s conversation, the panellists each left us with one tip that would assist with adaptation to the new normal.

Nigel urged people to look out for our neighbours, especially the elderly, during the extreme heat waves we’re anticipating. Adaptation is being led at the local government level, so we should aim to encourage our municipalities to embrace the strategies, developed in collaboration with our scientists.

Pandora urged people to ensure we stay informed by checking forecasts from the Bureau of Meteorology, including the Bureau’s new heatwave service, and then responding appropriately. She also encouraged people to check on neighbours and stay cool during warm weather events.

Ros unashamedly advocated for investment in plant adaptation science and urged us all to plant a tree – the right tree, suitable for a changing Victorian climate.

Richard’s tip was to support local farmers by purchasing local Victorian produce, as they will be bearing the brunt of economic disruption from Victoria’s changing climate, and will be making large transitions in the coming decades.

On close, guests were left to ponder and discuss the evening’s ideas with fellow guests and the panellists while enjoying the hospitality of the Governor and exploring the beautiful rooms of Government House.