DEA Hotspots

Digital Earth Australia Hotspots

Version
1.0.0 flat-square
Program
Digital Earth Australia
Resource type
Derivative
Date modified
09/09/2020

Background

Bushfires are a natural part of the Australian landscape. Many of our native flora and fauna have adapted to the specific fire regimes of the regions in which they live.

It is important we are able to accurately map and monitor fires on a near real-time basis. This information allows emergency services to control bushfires and develop risk assessments and disaster relief plans.

What this product offers

Digital Earth Australia (DEA) Hotspots is an internet-based national bushfire monitoring and mapping system run by Geoscience Australia to provide timely information to emergency service managers across Australia about 'Hotspots' (areas of elevated thermal spectral response).

The mapping system allows you to identify the locations of fire which create a potential risk to communities and property.

    Important: DEA Hotspots is not to be used for safety of life decisions.

    Applications

    This application allows you to visualise, search and download current and historic Hotspot data for any location Australia-wide.

    You can also overlay satellite passes, mosaics, topography, burnt areas, and other imagery sources such as ASTER, Landsat, Near Real-Time, Fractional Cover and Barest Earth.

    The system can be used by:

    • emergency services
    • climate change researchers
    • the media
    • policy makers
    • the broader public

    Data access

    Link to data DEA Hotspots
    eCat record 111881
    CMI RESTful node ID 167
    Security classification Unclassified
    Update frequency As needed
    Product life span -

    Technical information

    Important notes about Hotspots

    • Each Hotspot is represented by a spot on the map. The colour of the spot represents the time the Hotspot was last observed by a passing satellite (e.g. 0-2 hours). The colour does not indicate severity.
    • Hotspots are not an accurate measure for the size or location of the fire.  
    • The information on DEA Hotspots is not presented in real-time.  
    • DEA Hotspots is not designed to be used in isolation of other data sources. It is not accurate enough to be relied upon for time-critical detection and location of fires.
    • The Hotspot location on any map (no matter how detailed) is only accurate to 1.5 km at best.  
    • Hotspots are potential bushfires, but could also indicate other phenomena, such as gas fires, heavy industry, furnaces and jet contrails.  
    • Some Hotspots may not be captured and produced if associated imagery is missing.

    How Hotspots are generated

    1) Satellites regularly orbit the Earth and capture images of its surface.  
    For a given location in Australia, an image is captured 4-7 times per day by one of the satellites.
    Thermal infrared sensors on-board the satellites can detect areas with unusually high temperatures. We call these areas Hotspots.

    2) After each satellite pass, the images are transmitted to the Geoscience Australia ground station located in Alice Springs.  

    3) The thermal data is processed, and then added to the DEA Hotspots map.

    Typically, the entire procedure (from satellite imaging to Hotspot mapping) takes 30 mins. This means, at best, the data on DEA Hotspots is 30 mins old. It is not presented in real time.  

    Satellites and sensors

    The Hotspot data is collected by different satellites, including the following:

    Satellite On-board thermal sensor
    NASA Terra and Aqua Moderate Resolution Imaging Spectroradiometer (MODIS)
    NOAA Advanced Very High Resolution Radiometer (AVHRR)
    Suomi-NPP Visible Infrared Imaging Radiometer (VIIRS)

     

    Accuracy and limitations

    Missing Hotspots

    Hotspots may be obscured or missing from the map due to the following reasons:

    • Polar Orbiting satellites are not designed to provide live updates on fire fronts, as they only look over the fire ground 4-7 times per day.
    • Optical satellites cannot see though clouds, heavy smoke or tree canopy.  
    • Fires may be missed if they are relatively small or do not cover a spatial footprint large enough to be detected by the sensors (e.g. the MODIS footprint is 1km2).  
    • Cool fires are not likely to be detected.  
    • Sensors can be inoperable for extended periods of time, disrupting the detection of Hotspots.  
    • The fire may have been burning during a time when no satellite was looking over the fire ground.  

    False Hotspots

    At times, the AVHRR sensor on the NOAA satellites will register a line of false Hotspots which follow the path of the satellite pass. Usually, these can be seen moving from south-east to north-west along the edge of the sensor image. These should be disregarded as potential Hotspots.

    Owner

    Commonwealth of Australia (Geoscience Australia)

    License

    CC BY Attribution 4.0 International License

    Rights statement

    © Commonwealth of Australia (Geoscience Australia) 2015. Creative Commons Attribution 4.0 International License.