## 5 Agro-Climatic Mapping
### Estimation of Crop Potential Areas
This scheme uses a method for the estimation of global leaf area index (LAI) and fraction of photosynthetically active radiation absorbed by the vegetation (FPAR) from atmospherically corrected Normalized Difference Vegetation Index (NDVI) observations. LAI is defined as the one-sided green leaf area per unit ground area in broadleaf canopies and as one half of the total needle surface area per unit ground area in coniferous canopies. FPAR is defined as the fraction of incident photo-synthetically active radiation (400-700 nm) absorbed by the green elements of a vegetation canopy. The method requires stratification of global vegetation into cover types that are compatible with the radiative transfer model [42]. 4. The Net Primary Production scheme (NPP) with nine vegetation classes and two vegetation-free ones. NPP defines the rate at which all plants in an ecosystem produce net useful chemical energy. In other words, NPP equals the difference between the rate at which plants in an ecosystem produce useful chemical energy (or GPP, Gross Primary Production), and the rate at which they expend some of that energy for respiration. The Primary Production products are designed to provide an accurate regular measure of the growth of the terrestrial vegetation. Version-55 Terra/MODIS NPP products are validated to Stage-3; this means that its accuracy was assessed and uncertainties in the product were well-established via independent measurements made in a systematic and statistically robust way that represents global conditions. These data are deemed ready for use in science applications [43]. 5. The Functional Type Plant scheme (FTP) with nine vegetation classes, two vegetation-free and one ice-water class. While most land models developed for use with climate models represent vegetation as discrete biomes, this is, at least for mixed life-form biomes, inconsistent with the leaf-level and whole-plant physiological parameterizations needed to couple these bio-geophysical models with bio-geochemical and ecosystem dynamics models. In the calculation of this scheme, the authors present simulations with the National Center for Atmospheric Research land surface model (NCAR LSM) that examined the effect of representing vegetation as patches of plant functional types (PFTs) that coexist within a model grid cell. This approach is consistent with ecological theory and models and allows for unified treatment of vegetation in climate and ecosystem models [44]. The different classes included in the classification schemes are shown in Table 5. As can be seen, four of the five classification schemes include categories referring to agriculture, except the _NPP_ scheme that does not include any class related to croplands; therefore, it was not considered in the process. The classes corresponding to each crop are obtained and combined according to its leaf morphology. The obtained combinations for each one of the selected crops are listed in Table 6.  
To avoid inconsistencies among the classification schemes, we assume that an area was considered as a cropland only if at least three out of the four considered schemes agreed on it being a cropland area. Similar to the agro-climatic conditions, we obtained a final binary layer that represents the existence of detected croplands. This layer was also spatially crossed with the layer of agro-climatic conditions, thus obtaining the final map of potential crop areas.