DEA Fractional Cover Percentiles (Landsat)

Fractional Cover 25m Percentiles 2.2.1

Version
2.2.1 flat-square
Product ID
fc_percentile_albers, fc_percentile_albers_annual, fc_percentile_albers_seasonal
Program
Digital Earth Australia
Collection
Geoscience Australia Landsat Collection 2
Resource type
Derivative
Date modified
09/09/2020

Background

The Fractional Cover 2 (Landsat) product, developed by the Joint Remote Sensing Research Program, provides information about the the proportions of:

  • green vegetation
  • non-green vegetation (including deciduous trees during autumn and dry grass)
  • bare areas for every 25m x 25m ground footprint

It provides insight into how areas of dry vegetation and/or bare soil and green vegetation are changing over time.

It is important to be able to analyse and interpret fractional cover. For example, the 90th percentile of bare soil for a particular year will identify areas that have experienced a high portion of bare soil during that year.

What this product offers

This product is designed to make it easier to analyse and interpret fractional cover. It uses the Fractional Cover 2 (Landsat) product and calculates the statistical summaries (10th, 50th and 90th percentile) of fractional cover per epoch (whole-of-archive-summary, annual, seasonal).

This product is available in the following forms:

FC-PERCENTILE-SUMMARY

This contains a (10th, 50th and 90th percentile) of bare, green and non-green vegetation of all observations contained within the DEA (from 1987 to the most up to date imagery available).

FC-PERCENTILE-ANNUAL-SUMMARY

This contains a (10th, 50th and 90th percentile) of bare, green and non-green vegetation of observations acquired in each full calendar year (1st of January - 31st December) from 1987 to the most recent full calendar year.

FC-PERCENTILE-SEASONAL-SUMMARY

This contains a (10th, 50th and 90th percentile) of bare, green and non-green vegetation of observations acquired within each calendar season (DJF, MAM, JJA, SON).  This product is available for the most recent 8 seasons.

Applications

This product provides valuable information for a range of environmental and agricultural applications, including:

  • soil erosion monitoring
  • land surface process modelling
  • land management practices (e.g. crop rotation, stubble management, rangeland management)
  • vegetation studies
  • fuel load estimation
  • ecosystem modelling

Related products

Data access

Link to data THREDDS
Link to maps DEA Maps
eCat record 120843
Product ID fc_percentile_albers, fc_percentile_albers_annual, fc_percentile_albers_seasonal
CMI RESTful node ID 120
NCI project code rs0
Security classification Unclassified
Update frequency As needed

Access notes

DEA Maps

To view and access the data interactively:

1) Visit DEA Maps.

2) Click 'Add data'.

3) Select 'Vegetation' > 'Fractional Cover'.

4) Select which Percentile products you would like to display and click 'Add to map'.

Technical information

This product provides continental composites for each cover fraction.

The percentile ranges for each compositing period can be used to identify the 'greenest' observation i.e. 90th percentile of green cover and 'barest' observation i.e. 90th percentile of bare soil that occurred within the compositing period.

The 10th and 90th percentile are used in preference to the minimum and maximum values because they are less prone to residual noise associated with undetected cloud/cloud shadow. The 50th percentile (median) are used in preference to the mean as the median is less prone to being skewed by extreme values. It is worth noting that some undetected cloud and cloud shadow artefacts may still be present in the 10th and 90th percentiles, especially in areas with frequent cloud cover such as the wet tropics and Tasmania.

To account for satellite availability and status the statistics are calculated using the following satellites for the following periods of time:

  • 1987-1998 : Landsat 5
  • 1999 : Landsat 5 and Landsat 7
  • 2000-2002 : Landsat 7
  • 2003 : Landsat 5 and Landsat 7
  • 2004-2010 : Landsat 5
  • 2011-2012 : Landsat 7
  • 2013 onward : Landsat 8

The values for this product are scaled as follows:
For the fractional cover bands (PV, NPV, BS)
0-100 = fractional cover values that range between 0 and 100%

Due to model uncertainties and the limitations of the training data, some areas may show cover values in excess of 100%. These areas can either be excluded or treated as equivalent to 100%

For the unmixing error (UE) band, the values are scaled between 0 and 127  High unmixing error values represent areas of high model uncertainty (areas of water, cloud, cloud shadow or soil types/colours that were not included in the model training data). 

Lineage

Nationally consistent information about fractional cover dynamics is essential to addressing a range of natural resource challenges. These include land management practices, air quality, soil erosion, rangeland condition and soil carbon dynamics.

The fractional cover algorithm was developed by the Joint Remote Sensing Research Program (JRSRP) and is described in Scarth et al. (2010). While originally calibrated in Queensland, a large collaborative effort between The Department of Agriculture - ABARES and State and Territory governments to collect additional calibration data has enabled the calibration to extend to the entire Australian continent.

FC was made possible by new scientific and technical capabilities, the collaborative framework established by the Terrestrial Ecosystem Research Network (TERN) through the National Collaborative Research Infrastructure Strategy (NCRIS), and collaborative effort between state and Commonwealth governments.

The long term acquisition plan supported by the Landsat program, in combination with Geoscience Australia's longstanding investment in the on-ground infrastructure required to capture Landsat imagery has made this product possible. Geoscience Australia's partnership with the National Computing Infrastructure facilities in conjunction with the development of the Australian Geoscience Data Cube - a high performance data framework - makes it possible to analyse the continental archive of fractional cover data.

FC-PERCENTILE provides a consistent summary of fractional cover which will be an important foundation for land cover mapping and monitoring across Australia. It is a resource for natural resource managers, land surface process modellers, carbon modellers, rangeland managers, ecosystem scientists and policy makers.

Data sources

Processing steps

  1. Fractional Cover Processing

Major algorithms

Schema / spatial extent

DEA Albers Raster Schema

Update frequency As needed
Temporal extent
Min. longitude -1943830.00
Max. longitude 2170690.00
Min. latitude -1119030.00
Max. latitude -4856630.00
Coordinate reference system Australian Albers / GDA94 (EPSG: 3577)
Cell size X 25.00
Cell size Y 25.00

Owner

Commonwealth of Australia (Geoscience Australia)

Principal contributors

Leo Lymburner

License

CC BY Attribution 4.0 International License

Rights statement

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

Acknowledgments

Landsat data is provided by the United States Geological Survey (USGS) through direct reception of the data at Geoscience Australias satellite reception facility or download. The fractional cover algorithm was developed by the Joint Remote Sensing Research Program (JRSRP) and is described in Scarth et al. (2010). While originally calibrated in Queensland, a large collaborative effort between The Department of Agriculture & ABARES and State and Territory governments to collect additional calibration data has enabled the calibration to extend to the entire Australian continent. FC_25 was made possible by new scientific and technical capabilities, the collaborative framework established by the Terrestrial Ecosystem Research Network (TERN) through the National Collaborative Research Infrastructure Strategy (NCRIS), and collaborative effort between state and Commonwealth governments.