Annual Landsat Composite Imagery for Australian Landscape Monitoring

DEA Geometric Median and Median Absolute Deviation products provide annual cloud-free composite views of Australia's landscape. They are derived from Landsat satellite imagery to represent average conditions and variability for each calendar year. Geoscience Australia produces this data product for monitoring environmental change.

Use Cases

• Land cover mapping using the annual geometric median composite to identify stable and dynamic land types.
• Change detection analysis leveraging the median absolute deviation layer to quantify variability in areas like cropping or urban expansion.
• Validation of bio-physical models using the cloud-free, spectrally balanced pixel composites as input data.
• Burnt area mapping by analyzing deviations from the annual median reflectance values across spectral bands.
• Assessment of landscape stability by comparing geometric median values for features like bare rock versus agricultural areas.

Strengths

• Cloud-free composite mitigates data gaps from cloud cover.
• Annual compilation provides consistent yearly baselines for time-series analysis.
• Pixel-composite method improves color balance and spectral relationship consistency across bands.

Limitations

• Specific row count, column count, and file size metrics are unavailable.
• Geographic coverage is limited to Australia.
• Product version 4.0.0 suggests potential future changes to methodology.

Provenance

Source

Geoscience Australia Data.

Collection Method

Statistical analysis and pixel-composite algorithm applied to Landsat satellite imagery.

Time Range

Annual composites for each calendar year.

Freshness

Updated annually for each calendar year.

Geography

Australia.