Data Quality Assessment Scope
Certain features, associated with a negligible chance of cropping, have been masked from the maps, e.g. 'Conservation and Natural Environments', 'Intensive Uses', 'Water' or any type of forestry or horticulture, as defined by the Australia Land Use and Management Classification.
In winter, ‘Pulse' is often misclassified as ‘Cereal’. In summer, the “Other crop” class - which groups coarse-grain and pulse crops such as sorghum, maize, and mungbean - is the least accurately mapped, particularly in the western area of the QLD–NSW border. Pastures may be incorrectly classified as cropping, particularly in wet years or in seasons when rapid green-up occurs at a similar time to actively growing crops. Formerly-cropped land that is not currently under cultivation may still appear as cropped if the vegetation greens-up during the growing period, e.g. weeds or redundant or abandoned crops and crop residue are dominating the ground cover. A failed crop can only be detected if it reached a certain level of greenness, which may vary between region, seasons and years. Vegetated areas around watercourses and dams may be classified as crop due to the strong greening-up phase after rainfall events. Some areas of shallow water or water with emergent or floating vegetation may be incorrectly classified as cropped, due to seasonal patterns in greenness that may be similar to crops. Areas with steep slopes (i.e. a slope of greater than 10%) are excluded. Inaccuracies in the DEM used for identifying these areas may result in some areas being included. From 2025 onward, manual editing of the crop map was carried out through image interpretation to correct the most critical errors, using Sentinel-2 and Planet imagery, as well as Google Earth, as ancillary data.
Data Quality Assessment Outcome
In summer, notional user's accuracies are: “Banana” = 99%, "Cotton" = 87%, "Sugarcane" = 98%, and "OtherCrop" = 98%. In winter the user's accuracies are: "Cereal" = 89%, and “Chickpea” = 73%. User’s accuracies cannot be reported as anything more than notional approximations, due to sampling constraints.