Geoglam best available crop-specific global maps: Strengths and limitations

Abstract

An accurate global map of current cropland is needed to tackle the agricultural challenges of the next decades. Several remote sensing products have provided with global cropland maps. To create the GEOGLAM best available global crop-specific maps, we integrated the SPAM 2005 with regional maps developed by different countries and international organisms. The comparison with other available global cropland products showed a clear linear agreement between products and a tendency towards overestimation of GEOGLAM best available global crop-specific maps. In addition, a sensitivity analysis was performed using the forecast production model for winter wheat developed in previous studies. It showed how at constant values of adjusted NDVI small variations of cultivated area (5000 ha) produced a 17% rate of variation in the estimated production values.

An accurate global map of current cropland is needed to tackle the agricultural challenges of the next decades. Several remote sensing products have provided with global cropland maps. To create the GEOGLAM best available global crop-specific maps, we integrated the SPAM 2005 with regional maps developed by different countries and international organisms. The comparison with other available global cropland products showed a clear linear agreement between products and a tendency towards overestimation of GEOGLAM best available global crop-specific maps. In addition, a sensitivity analysis was performed using the forecast production model for winter wheat developed in previous studies. It showed how at constant values of adjusted NDVI small variations of cultivated area (5000 ha) produced a 17% rate of variation in the estimated production values.