Living with grassfires in Australia

Fire is one of the most important elements in the Australian landscape with an average of over 2.5 million hectares burnt in bushfires each year.

“Grass is the most common bushfire fuel type in Australia,” says author and CSIRO bushfire researcher Andrew Sullivan. “Grasslands cover nearly 75 per cent of the country, ranging from treeless plains, to areas cleared for agriculture or grazing, to open forests with a history of regular burning.”

“During the 11 years since the first edition of this book, our research has increased our understanding of key influences of bushfire behaviour such as wind and combustion.

“Understanding how a grassfire behaves and, most importantly, how its behaviour can vary from what is predicted, is vital to the safety of anyone involved in fighting grassfires or who may be caught in a grassfire.”

The new edition includes updated information on combustion of grassy fuels, the effect of weather and topography on fire behaviour, Aboriginal burning practices in grasslands, and more historical bushfire events.

It also discusses the CSIRO meters for predicting fire danger and fire spread in Australia, different fire fighting strategies and how to reconstruct grassfire spread after the fact.

The book also looks at some of the myths that surround grassfires and how these myths can compromise personal safety and survival.

For example, it is widely believed that a grassfire can become self-perpetuating by generating its own wind.
The fact is that while it is true that convection caused by the heat of a bushfire draws in air that can increase or decrease the effect of the prevailing wind, sometimes to quite violent levels, the effect is relatively localised and a grassfire can’t spread independently by this wind. Instead it will spread in a direction and at a speed determined by the prevailing wind and topography.

Myths that suggest fires are like an atomic bomb, can use all of the oxygen in the air so that people can’t breathe, that there is a danger of being boiled alive if taking refuge in shallow water bodies, or that a grassfire can outrun a speeding car are all dangerous. They make grassfires appear much worse than they really are and may cause people to panic and make unsafe decisions. The book explains these and other myths and their implications for personal safety.

Grassfires: Fuel, Weather and Fire Behaviour, by Phil Cheney and Andrew Sullivan is published by CSIRO Publishing. It can be purchased from www.publish.csiro.au/nid/21/pid/5971.htm and costs A$39.95.

It is recommended for rural landholders, students and the fire fighting community.

Download image at: Living with grassfires in Australia.