Agricultural land comprises 14% of total area burned by Australian bushfires

Digital Agriculture Services found a strong correlation between drought-affected and fire-hit land, with 86% of fire-hit land suffering at least a 1-in-10-year rainfall deficit.

The extent of agricultural land affected by Australia’s bushfire crisis has been revealed, with upwards of 820,000 ha impacted as of January 15.

Digital Agriculture Services, an agtech start-up that has developed detailed maps to allow automated valuations of farmland in Australia, found that 820,385 ha of agricultural land was located within fire boundaries – more than 14 percent of the total land area that has burned.

New South Wales has seen the most extensive damage, with 558,878 ha of agricultural land affected, while Victoria has seen 161,717 ha hit. South Australia has had 98,966 ha of agricultural land affected so far, while 825 ha has burned in Tasmania.

The final figures are likely to be higher, with some time left to run on the current fire season. The figures also do not include statistics from Queensland and Western Australia, as the respective governing bodies in each state have not publicly released the data.

In addition, huge areas of forests and plantation have burned: 1,595,519 ha in total, or 28 percent of the total land burned.

DAS generated the data by overlaying fire boundary maps developed and maintained by Emergency Management Spatial Information Network Australia (EMSINA) – with the assistance of Geoscience Australia staff – onto land use maps developed by the Australian Bureau of Agricultural and Resource Economics and Sciences (ABARES). EMSINA is a group of practitioners who use spatial information technologies to support decision-making in the emergency management sector.

DAS also overlaid the bushfire boundary map onto land suffering from drought to find a strong correlation between drought-affected areas and those that have been hit by fire.

It found that 63 percent of the fire-affected area in NSW, VIC, SA and TAS is experiencing a 1-in-20-year rainfall deficit, and 86 percent of the fire-affected area in the same states is experiencing at least a 1-in-10-year rainfall deficit.

Anthony Willmott, co-founder and CEO of DAS, told Agri Investor: “Scientifically, we knew that climate change was driving impacts on drought, and we knew that drought was driving an impact on fire and fire risk – but to see it displayed like this is really powerful.”

The data showed, too, that 49,801 structures (defined as any building more substantial than a garage) were located within the bushfire boundaries in the four states, but it does not suggest that all of those structures were destroyed.

DAS worked with the Commonwealth Scientific and Industrial Research Organisation (CSIRO) in 2018 to develop a fire risk score for all Australian rural properties. Using the fire boundary maps, it found that the mean fire risk score for properties inside the fire-affected areas was 0.93 (the maximum score is 1).

Map of eastern NSW: National fire risk index with new bushfires boundaries overlayed in red. White denotes a risk of zero; black represents a fire risk index of 1

Map showing Australia fire risk index

Source: Digital Agriculture Services

The highest risk scores show where crown fires and firestorms are most likely to develop, while the lowest score would indicate an area where a fire would struggle to stay alight.

“This captures the pre-existing risk of fire to properties and assets. Fire risk is really an estimate of the likely impact of a fire that happens below ‘catastrophic’ level: its likely intensity and its ability to impact the land. [The average rating of 0.93] gives you a sense of the pre-existing fuel loads and propensity for risk,” Willmott said.

Willmott added that the next step for DAS is to analyze the value of rural properties affected by fire, using DAS’s data that includes 10 years of sales data for every property, as well as the impact on productivity using data going back 17 years. This would take “some time,” he said.