In the future, heatwaves are very likely to be longer and occur more often, according to the Intergovernmental Panel on Climate Change. CSIRO and the Bureau of Meteorology have estimated that in Adelaide the annual average number of days over 35°C may increase from 17 days to 24–47 days by 2070.
This means that we need to take action now to reduce greenhouse gas emissions, both at an individual and at a collective level. We also need to work together to understand how climate change will affect the different aspects of our lives, and how we are going to deal with these impacts.
While the thought of change often makes people feel unsettled, there are many ways we can improve our lives and the way we go about our business. We need to work together to identify opportunities for positive change.
The challenge that climate change brings is that we don’t know precisely what is going to happen or exactly how natural systems will respond. We therefore need to be more flexible in our thinking, increasing our capacity to adapt our responses and behaviour as required, and to imagine and create a better future.
What does climate change mean for Australia?
Of all the world’s developed nations, Australia is among the most exposed to extremes. The storms, flooding, drought, wildfires, coral bleaching and other disasters that are occurring across the country exact a high social, economic and environmental cost. Continued emissions of greenhouse gases will cause further warming and changes in all components of the climate system. This represents a significant challenge to individuals, communities, governments, businesses and the environment, and time is of the essence if the worst outcomes are to be avoided. Unfortunately, Australia’s greenhouse gas emissions continue to rise and in 2017 were the highest on record, with Australia also being one of the highest per capita emitter of greenhouses gases in the world.
What are the impacts of climate change?
The impacts of climate change on our industry, economy, society and environment are far wider ranging and potentially devastating than just the prospect of balmier, tropical weather. While the global impacts of climate change are indisputable, specific impacts can vary at local and regional levels.
Sea level rise is driven both by the expansion of seawater as it warms and the melting of icecaps and glaciers. Recent evidence indicates that it may be far more rapid and extreme than currently anticipated. This will be felt both through changes in mean sea level and through changes in frequency of extreme storm surge events. Depending on local conditions, events that currently occur once every 100 years could increase dramatically and occur many times per year by 2100. Homes and coastal infrastructure are at risk from flooding and erosion and significant planning and subsequent action is required to reduce and mitigate these risks.
Highly accurate LIDAR data has been used to map current sea level for eastern Kangaroo Island so that we can plan for potential sea level rise over coming centuries.
Warming oceans also pose a significant threat to the marine environment through biological changes in marine species, including local abundance, community structure, and enhanced coral bleaching risk.
Ocean acidification occurs as the ocean absorbs about a quarter of the CO2 we release into the atmosphere every year. When CO2 is absorbed by seawater it turns into carbonic acid and the pH drops. Since the beginning of the Industrial Revolution, the acidity of surface ocean waters has increased by about 30%. Studies have shown that a more acidic environment has a dramatic effect on the ability of species with hard shells to build and maintain those shells. This includes oysters, cockles, sea urchins, corals and vast numbers of plankton. When shelled organisms are at risk, the entire marine food web is also at risk. More than a billion people on the planet are currently reliant on fish and seafood for their primary source of protein and will also be affected.
Temperatures have increased over the past century, with the last few years being the hottest on record. Average maximum temperatures recorded at Cape Borda have risen by nearly 1.5°C in just the last 50 years. As the global climate warms, colder years and cold snaps will still occur from time to time. However, in Australia and elsewhere we are already seeing fewer very cold days and many more very hot ones.
Extreme weather events and increased fire risk result as extreme hot days in Australia are getting hotter, with the rate of very hot (greater than 35°C) daytime temperatures increasing since the 1990s. Heat waves are forecast to become more frequent and intense, with the number of very hot days in major cities doubling by 2070. This will have consequential effects on heat-related deaths, infrastructure performance, energy demand, housing design and urban planning. In addition weather associated with high fire danger has shown a rapid increase and will continue to rise.
Rainfall is likely to decline across South Australia, most notably in winter and spring. This will lead to a greater frequency and/or severity of drought, with decreased flows in water supply catchments. However, despite a drier average there may also be more floods due to an increase in extreme rainfall events. The southward shift of winter storm systems and greater prevalence of high pressure systems are the physical mechanisms that have driven decreases in winter rainfall.
Species and ecosystems restricted to Kangaroo Island are likely to be among the most vulnerable to climate change. Organisms that have adapted to the prevailing climate over thousands of years will have limited room to move given the large extent of the coastline and limited altitudinal gradient, and will have little time to evolve as the world changes rapidly around them, or to migrate to areas where the conditions may be suitable for their survival. Novel ecosystems may arise, with species and assemblages that are different to those that currently exist at any given location.
Agriculture and food production will be negatively impacted by higher temperatures, higher evapotranspiration, reduced rainfall and more frequent extreme weather events, as well as by natural resource degradation such as soil erosion and salinity, and increases in pests and diseases. Since 1997, South Australia’s agricultural regions have experienced a marked decline in growing season (April–September) rainfall. Season breaks are occurring later, and bringing less rainfall. Rising temperatures are likely to have a major influence on wine grapes, bringing the harvest forward by a month and yielding lower quality grapes. Erratic and high temperatures also have an effect on flowering plants, the production of honey and on pollinators such as bees. Weeds and weed management will be affected.
Human health and wellbeing will be impacted as the number of very hot days with increasing heat-related illnesses and death, particularly the elderly. There may also be a higher prevalence of certain debilitating diseases such as dengue fever in certain regions and disease vectors such as mosquitoes.
What changes can Kangaroo Island expect?
To assist the planning and management of NRM regions, CSIRO and the Australian Bureau of Meteorology have prepared climate change projections for eight regions of Australia, termed NRM clusters. Kangaroo Island is a part of the Southern and South-Western Flatlands (SSWF) Cluster. Projections for SSWF are based on the outputs of a set of 40 global climate models (GCMs) developed by Australian and international scientists. Climate models are based on established laws of physics and are rigorously tested for their ability to reproduce past climate. These projections draw on the full breadth of available data and peer-reviewed literature to provide a robust assessment of the potential future climate. Projections for SSWF are based on four Representative Concentration Pathways (RCPs) underpinned by emission scenarios.
For more information on what the projections are for this cluster, please click here
The climate analogues tool matches the proposed future climate of a location of interest with the current climate experienced in another location using annual average rainfall and maximum temperature. For example, by 2050 under a high emissions scenario, Kingscote could have a climate that is similar to that of Horsham, Bordertown, Keith and Port Lincoln.
Mitigation and adaptation
There are two main categories of human responses to climate change: mitigation and adaptation. Both types of response help to reduce the risks of climate change.
Mitigation refers to actions we can individually and collectively take to reduce the future magnitude and rate of climate change. This means drastically reducing our emissions of greenhouse gases, especially carbon dioxide and methane, to reduce future risk and cost.
Adaptation refers to measures we can take to prepare for and cope with the climate change that can no longer be avoided. Actions aim to reduce the impacts of a warming climate on humans and the natural world. Adaptation presents new challenges for business and policy decision-makers - it will take time to build the skills and knowledge needed to make the best decisions. Adaptation planning will enable Australia to reduce negative impacts of climate change and to take advantage of any positive effects.
If decisions about major infrastructure investment, land use planning and building design don’t take climate change into account, they may create greater costs and risks in the future. Different planning tools are available to consider climate change, such as the adaptive pathways approach.
How is Kangaroo Island responding to the climate change challenge?
The new KI NRM Plan 2017-2027 was developed with the known implications of climate change in mind. Section 8 of the plan outlines various objectives and strategies for responding to climate change. For example, it recommends the identification and protection of climate change refugia – areas where a large number of endemic species may be able to persist in the future. Water resources management is seen to be another important area that requires careful consideration so that equitable access to this precious resource is safeguarded as the Island warms and dries in the future.
Natural Resources Kangaroo Island and the Kangaroo Island Council are partners in the Resilient Hills & Coasts Initiative and worked together with local stakeholders to develop a regional climate change adaptation plan that starts to consider how we might respond to emerging challenges in a logical and step-wise fashion.
What can I do?
At a personal and household level there are steps you can take to mitigate and adapt to climate change – check out these tips
Joint KI NRM Board and KI Council Position Statement
In response to the looming challenges posed by climate change and the need for solid leadership on the matter, the board and the council have developed a joint climate change position statement.
BIG issue paper on climate change
A BIG issue paper has been developed on climate change strategies for Kangaroo Island as an outcome of community consultations in 2014.