# Creating a Regional MODIS Satellite-Driven Net Primary Production Dataset for European Forests
## 5 Conclusions  
In this study we created a regional Net Primary Production (NPP) dataset by running the MOD17 algorithm with local European climate data on 1-km resolution for the years 2000 to 2012 (MODIS EURO). We additionally obtained the global MODIS NPP product (MODIS GLOB) and evaluated the two MODIS NPP datasets with bottom-up forest inventory driven NPP (NFI NPP). We thus compared two conceptually different methods for assessing forest productivity across Europe, and test whether local climate data enhances the ability of the MOD17 algorithm to capture European forest conditions. Running the MOD17 algorithm with local daily climate data substantially improves the quality of MODIS satellite-driven NPP across Europe as compared to the global NPP product (MODIS GLOB). Top-down satellite-driven MODIS EURO and bottom-up NFI NPP agree by regions and by countries, across gradients by longitude, latitude and elevation, if potential discrepancies by stand density due to forest management or the used carbon estimation methods are addressed. This newly created MODIS EURO dataset is a consistent, continuous, spatial and temporal explicit forest productivity measure of the European forest area providing realistic estimates, which compare well with forest inventory information. This is important since reliable wall-to-wall forest productivity estimates are increasingly important for the growing bio-economy or for increasing our knowledge on other forest ecosystem services such as carbon sequestration. As long as the MODIS program (based on Satellite \"Terra\" launched in 1999 and \"Aqua\" in 2002) is operational and local climate data is available, we can obtain reliable large-scale forest productivity measures for European forests. Since the lifetime of the satellites carrying the MODIS sensor is unknown, we strongly suggest the implementation and testing of this concept in the upcoming European satellite technologies such as the Copernicus Programme to ensure consistent and realistic productivity estimates also in the future. MODIS EURO data are made freely available for 2000 until 2012 under [[ftp://palantir.boku.ac.at/Public/MODIS_EURO](ftp://palantir.boku.ac.at/Public/MODIS_EURO)]([ftp://palantir.boku.ac.at/Public/MODIS_EURO](ftp://palantir.boku.ac.at/Public/MODIS_EURO)). The following are available online at www.mdpi.com/2072-4292/8/7/554/s1, Table S1: Summary of the properties of the different forest inventory datasets, Table S2: Tree species groups used in this study, description and selected tree species, Figure S1: Direct pixel-to-plot comparison of MODIS EURO and NFI NPP, Figure S2: For North Europe ANPP grouped by Elevation, Latitude and Longitude, Figure S3: For Central-West Europe ANPP grouped by Elevation, Latitude and Longitude, Figure S4: For Central-East Europe ANPP grouped by Elevation, Latitude and Longitude, Figure S5: For South Europe ANPP grouped by Elevation, Latitude and Longitude, Figure S6: Difference ANPP grouped by age classes, Figure S7: Difference ANPP grouped by tree height classes, Figure S8: Difference ANPP grouped by MODIS Land cover types, Figure S9: Difference ANPP grouped by dominant species, Figure S10: MODIS EURO and NFI NPP by Stand density Index (SDI) classes. This work was conducted as part of the collaborative project \"FORest management strategies to enhance the MITgation potential of European forests\" (FORMIT). The research leading to these results has received funding from the European Union Seventh Framework Programme under grant agreement n\({}^{\circ}\) 311970. Special thanks to all the field crews collecting the sample data for the inventory plots. We are also grateful to the responsible people from the various forest inventory organizations for providing us with the data of their forest inventory systems and thereby making this work possible in the first place. We also want to acknowledge the open data policy of NASA and the work of the MODIS land product science team providing us with the FPAR and LAI products.