Fires and smoke in Southeast Australia
Jacques Descloitres, MODIS Rapid Response Team, NASA/GSFC
A change in the wind direction has shifted the smoke billowing from bushfires in southeast Australia from east to west. This true-color Moderate Resolution Imaging Spectroradiometer (MODIS) image from the Aqua satellite on January 23, 2003, shows the fires (red dots) burning near the New South Wales-Victoria border. The change in wind direction has allowed fire fighters to employ a technique called back burning, protecting several towns in the region.
When the wind is pushing a fire in one direction, it can be dangerous for firefighters to get too close to the advancing fire in an attempt to create a control line, for example, by digging a fire break. But when the wind changes direction, often pushing the fire back the way it came, firefighters can establish a control line in relative safety aware from the fire front, and then intentionally burn the vegetation between the control line and fire. The intentional burn will then "chase" the main fire, clearing the vegetation and creating a zone of relative safety for the firefighters for when the winds resume their previous course.