Just before the pandemic, bushfires in Australia destroyed more than 3,000 homes and burned millions of hectares of vegetation. The crisis exposed the country’s fire monitoring system as being unfit for purpose. Accurate real-time information about the burned area and fire intensity was not available when it was needed.
There is no central system in Australia to collect and store essential information about bushfires. State and regional governments, and even agencies within states, have differing perspectives. It worked fine when the fire was low. But in the 2019-20 season, those people crossed the borders of many states.
The blazes covered a vast geographic range and burned for a duration and intensity that was beyond the experience of communities and fire managers. Many Australians endured five months of smoke pollution that violated national air quality standards. Typically, people will experience short bouts covering smaller areas.
The extraordinary scale and intensity of the fires was driven by climatic conditions not seen in a century: a three-year drought, consisting of three consecutive, anomalously dry winters. This is in line with weather forecasts that the risk of fires will increase as a result of global warming. Studies have linked extreme bush-fire seasons to anthropogenic climate change over the past few years6,7.
The debate over the causes of the bushfires became politically charged. Fire scientists and managers had to withhold misinformation from politicians and the media, suggesting that fires were not historically uncommon and not linked to climate change.
It was also suggested that the fire was the result of arson, or improper land management 8–10. Staggering environmental consequences were claimed, including greenhouse-gas emissions that exceeded only those in China, the United States, India, Russia and Japan, and the loss or displacement of more than a billion native vertebrates.
Such a claim can only be verified or rebutted through credible data. Fire Record’s current patchwork cannot meet that.
Here we present a more useful picture – the analysis of satellite data relating to set burnings in the context of historical fire records. We calculate that a much smaller area than estimates compiled from government fire records was engulfed (see ‘Excessive burning’).
Yet we still show that nothing like this has been observed since at least the mid-nineteenth century. The geographic scale behind a series of giant bushfires that have engulfed southern Australia and Tasmania since the beginning of this century assumes a worst-case scenario designed to prepare agencies and communities.
In other words, we are navigating into unknown territory without a compass. Effective adaptation to such extreme events demands more detailed description and analysis, and requires accurate and timely data.
We call on researchers and policymakers to create a dedicated national bush-fire monitoring agency. This is essential to provide the relevant information needed for cost-effective, evidence-based fire management and mitigation. Only in this way can we strengthen Australia’s resilience to climate change.
Australian state and territorial governments record bushfires in a number of ways. In vast tropical savannas and dry grasslands, fire mapping relies on satellite assessments. In temperate forests, the fire perimeter is mapped by ground crews, aerial surveys, and satellite analysis. All areas assess severity differently.
This has led to discrepancies and gaps in the data. For example, some reports overestimate the burned area because they include burn patches. In addition, different states and territories survey the distribution of animals, causes of fires, and types of vegetation in different ways.
The lack of consistent basic data makes it impossible to accurately measure the scale and environmental impact of fires. In addition, extraordinary claims about the causes and consequences of bushfires cannot be investigated.
For example, is it true that a billion animals were killed or displaced in the last fire season? This claim rests on estimates of the area burned, assumes a uniform fire intensity and ignores the fact that wildlife may have taken refuge in unirrigated areas.
And did the fire actually put about 830 million tons of greenhouse gases in the atmosphere? This value depends on the type of vegetation burned and the extent and severity of this season’s fires, as well as the previous ones. For example, previous research has shown that a massive fire in a dry eucalyptus forest emitted 16% of total carbon, yet a nearby area that was subject to scheduled burning emitted only 9%.
Despite clear evidence that the main fault lies in extreme weather conditions induced by climate change, disputes about the causes of fires have also been raging.