A man standing on the steps above the flooded Brisbane River.

Extreme weather events include flooding, cyclones and heatwaves as well as frost and hail.

Extreme weather events - what can we expect?

CSIRO scientists are using a number of different methods to predict the risk of occurrence of severe weather events.

  • 19 January 2011 | Updated 14 October 2011

Background

Extreme weather events can bring high winds and coastal storm surges, driving rain or no rain for long periods, sudden frosts and storms of hail.

The damaging impacts from these events are brought through drought and flood, erosion from winds and debris and extended or abrupt temperatures beyond the survival range for some plants and animals.

Climate change involves long-term changes to the underlying ocean and atmosphere patterns that generate these events as part of year-to-year climate variability.

Australia is likely to become warmer over the coming decades, with a reduction in average annual rainfall in the south-east, and uncertain changes in average annual rainfall in the north.

Climate variability from year to year and within years will be superimposed on these trends in average conditions. For example, a warming trend will include some cool years and many hot years, and a drying trend will include some very wet years and many dry years. 

These natural disasters have an enormous social and economic cost. Knowing more about their occurrence will facilitate better preparation by the community.

In this highly variable climate, future severe storms and extreme rainfall events are likely to be more intense resulting in more severe flooding.

These natural disasters have an enormous social and economic cost. Knowing more about their occurrence will facilitate better preparation by the community.

Our research

CSIRO scientists are using a variety of methods to model the behaviour of climate and weather extremes for current and projected conditions. For example, in the Sydney region hailstorms have been the most damaging type of natural disaster and much of the urban population of Sydney is located in the most hail prone area of the city.

Scientists are having success with a method that uses diagnostics of the broader weather system to infer the risk of occurrence, rather than forecast a particular event.

This method suggests hailstorms are likely to increase along the coast of New South Wales, Australia, with the risk of large and damaging hail projected to almost double, increasing by between four to six days a year.

Read more about Climate Change research.