Extreme fire weather risk projected to rise across Australia

Fire weather projections across Australia

Extreme fire weather events are projected to become more frequent and more intense across Australia as global temperatures rise, with some of the sharpest changes expected in fire-prone forest ecosystems in the southeast.

A study published in npj Natural Hazards examined changes in fire weather using the McArthur Forest Fire Danger Index (FFDI) together with dynamically downscaled CMIP6 climate model projections.

The research was carried out by researchers from the Queensland Future Climate Science Program, the University of Queensland and the University of Melbourne.

It found that under 3°C of global warming, weekly extreme fire weather events that historically occurred once every 20 or 50 years are projected to become much more common across Australia.

Across southeast Australia’s eucalypt forests, the study estimates that these events could become about 2.1 times and 2.5 times more likely under 3°C of warming.

In Tasmania, comparable events may become about 3.2 times and 4.1 times more likely.

Fire weather refers to atmospheric conditions that affect the ignition and spread of wildfires, including temperature, humidity, wind speed and rainfall patterns.

The FFDI combines these factors to estimate potential fire behaviour.

The analysis also found that severe fire weather days, defined by an FFDI of 50 or higher, are projected to increase across much of Australia.

The largest increases in severe fire weather days are projected in northwestern and central regions.

Days classified as “Very High” fire weather are also expected to increase in northern and southern parts of the country.

Fire weather in forest regions and future planning

The study states that southeast Australia’s forest ecosystems remain a key area of concern because these regions have historically experienced destructive bushfires.

For eucalypt forests across southeast Australia, the magnitude of rare fire weather events could increase by about 10% under 3°C of warming.

Tasmania is projected to see stronger changes in both the intensity and likelihood of extreme events than other regions covered in the study.

The findings suggest rising maximum temperatures will be a main driver of higher fire weather risk.

In southern forest regions, falling humidity and higher drought conditions are also projected to increase the potential for intense fires.

The study also states that changes in large-scale climate patterns, including the El Niño-Southern Oscillation and the Southern Annular Mode, may affect future fire weather through changes in wind patterns, rainfall and humidity.

The researchers found that fire weather seasons may lengthen in several regions, with more dangerous conditions projected during spring, autumn and winter.

The study states that understanding these changes is important for future resilience planning, including wildfire preparedness, land management and building standards in bushfire-prone areas.

By combining high-resolution climate projections with detailed fire weather analysis, the research sets out how warming temperatures may reshape wildfire risk across Australia in the coming decades.