The Commonwealth Scientific and Industrial Research Organisation (CSIRO) has rounded up a few of its experts to answer questions about the country’s recent wild weather and the impacts of climate change.
Senior hydrologist at CSIRO, Francis Chiew said Australia’s climate was highly variable with many different drivers such as the El Niño and La Niña cycle, and the effects of climate change would be superimposed on this natural variability.
“We can attribute the contribution of climate change on some extreme events with confidence, including the role in heat extremes on land and in the ocean,” Dr Chiew said.
“However, due to the complex drivers of extreme rainfall and floods, and the highly variable nature of rainfall, we are less confident about attributing the relative contributions of different factors right now,” he said.
“That analysis will take a few months.”
Dr Chiew said that under a warmer climate, flood risk in general was likely to increase.
Senior climate researcher at CSIRO, Michael Grose said the United Nations’ Intergovernmental Panel on Climate Change’s (IPCC) Sixth Assessment Report indicated that the frequency and intensity of extreme rainfall had already increased over most land regions, and extreme rainfall would generally become more intense under a warmer climate.
“This will increase flood risk in cities, in built-up urban areas and in small catchments, where extreme rainfall over hours to a day can quickly become flash floods,” Dr Grose said.
“It’s more complex in rural areas and for larger river basins, which are driven by multi-day rainfall events and by the preceding catchment conditions,” he said.
“For example, in southern Australia, the change in flood risk will be the net result of contrasting effects of increases in extreme rainfall and generally drier catchments under climate change.”
Dr Grose said the UN’s IPCC Report gave medium confidence that risks from river flood would increase with climate change.
Senior climate researcher at CSIRO, Kevin Hennessy said Australia’s recent fires and floods highlighted the vulnerabilities in Federal, State and Local Government climate adaptation plans.
Mr Hennessy said barriers to adaptation included a lack of consistent policy direction; competing objectives; different risk perceptions and values; knowledge constraints; inconsistent information; fear of litigation; up-front costs; and lack of engagement, trust and resources.
“The good news is that a range of incremental and transformative adaptation options and pathways is available,” he said.
“Key enablers include shifting from reactive to anticipatory planning, integration and coordination across levels of Government and sectors, inclusive and collaborative institutional arrangements, Government leadership, policy alignment, nationally consistent and accessible information, decision-support tools, along with adaptation funding and finance.
“Recent initiatives like the Australian Climate Service, the National Recovery and Resilience Agency and Future Drought Fund, are positive steps to helping address risks from floods, fires, droughts, heatwaves and other hazards,” Mr Hennessy said.
