How will society have to adapt to climate change?
It’s important firstly to distinguish between mitigation and adaptation when we are talking about climate change. Mitigation means all those actions intended to lessen climate change, mainly by reducing greenhouse gas emissions and enhancing nature’s ability to absorb emissions. Mitigation includes things like transforming our energy, transport and manufacturing systems so that we can move away from fossil fuels. It also includes helping nature to recover with tree planting and habitat restoration so that natural environments can help us do the work of reaching net zero emissions by absorbing carbon dioxide. However, even if we can cut global emissions in half by 2030 and reach net zero emissions by 2050 – the key goal of the 2015 Paris Agreement – impacts of climate change will continue to be felt for some time. We will therefore need to work on adaptation: that is, changing our societies to better cope with the impacts of climate change already being felt and the impacts projected into the future.
One of the key things we need to think about is adapting to sea level rise. Scientists from the Intergovernmental Panel on Climate Change (IPCC) tell us even if we succeed in strongly reducing emissions, greenhouse gases already in the atmosphere and heating already in the climate system will mean that sea levels continue to rise for centuries. Sea levels could rise by 30-60cms by 2100, even if global warming is kept below 2°. Seas could rise as much as 60-110cm by 2100 if we don’t curb emissions strongly. In any future emissions scenario, therefore, coastal areas and low lying land areas will have to adapt to saltwater flooding from sea level rise. In some cases this may mean building extensive sea walls: such adaptation infrastructure is now being considered by low-lying cities, for example Miami in Florida, USA. In other places, like low-lying Pacific Islands, this may be less feasible and moving away from such islands may be a necessary adaptation action. For example, people living on the Carteret Islands in Papua New Guinea are already having to decide to leave their islands, as sea levels rise.
Increasing heat will also call for adaptions. Heatwaves are Australia’s most dangerous extreme weather risk for humans. Heatwaves are becoming hotter, lasting longer and occurring more often. By mid-century in Australia, we expect to see an increasing number of days on which there is severe heat danger for people working outside. Outdoor work normally done in the daytime may need to be undertaken at night (eg: agricultural work). Architecture of homes to allow more natural cooling and of cities to reduce the urban heat island effect with planting of more trees are possible adaptations.
In a heating world, we will also need to be better prepared for bushfires – particularly in Australia. This may mean further upgrading of building codes to make every house in bushfire-prone areas more bushfire ready. Though we can better protect houses by clearing vegetation around them, houses in some areas may not be able to be adequately protected from fire. This could mean that one climate change adaptation we may see in the future is whole communities needing to move out of particularly bushfire-prone areas.
Some impacts of climate change may allow for potentially positive adaptations. For example, in Tasmania, overall warming may allow for a change of land use choices in agriculture, with potentially higher economic returns. Climate modelling for Tasmania shows that by 2085, pasture production of ryegrass for livestock could increase in some areas by 10-100% due to an earlier start to spring and therefore a longer growing season. Wheat cropping in some parts of Tasmania could see a 10-15% increase in yields. However, agricultural pests (eg: fruit fly) could become a problem for agriculture in a warmer Tasmania. Farmers will therefore need to adapt on several levels.
