NDVI Differences: comparison between the vegetation indices of January 2008 and those of the historical average.

The dataset of differences of dry NDVI (Standard Difference Vegetation Index) for the month of January 2008 of the study of Monitoring the Annual Evolution of Crops and Harvests contains the January map of percentage differences in vegetation indices between the average monthly value of the 2008 agricultural season and the average monthly value of the historical average (average year) of the whole series of years of which images are available, for the entire area of dry and grassland in the regions studied. To obtain these results, the Ministry of Agriculture and Fisheries, Food and Environment (MAPAMA) has a system for monitoring the evolution of dry and grassland crops, based mainly on the information provided by vegetation indexes (NDVI) generated with daily satellite images NOAA-AVHRR. This system has been in operation since 1993, paying particular attention to the detection and tracing of drought situations throughout successive agricultural campaigns, in order to provide for the measures that need to be taken to mitigate their effects. The system is in operation between the months of January and June, a period in which the studied crops are developed. The study is carried out in the autonomous communities of Navarra, Aragon, Catalonia, Castile and Leon, La Rioja, Madrid, Castilla-La Mancha, Valencian Community, Andalusia, Murcia Region, Extremadura and Balearic Islands, as they comprise almost all dry crops and grasslands.