Using Copernicus Data and Growth Modelling to Globally Assess Virtual Water Flows in Agricultural Production - the Viw a Concept

The water- food-energy nexus intimately binds food and energy production to water use. The largest fraction of today's water use is through food and energy production in agriculture. Water use in agriculture, however, is predominantly wasteful and not sustainable, due to over-exploitation of scarce water resources on one hand and through inefficient use of water on the other. So far, no global monitoring system for efficiency and sustainability of agricultural water use exists. Both quantities thus are largely unknown especially on a global level. This leads to the limitation that efficiency and sustainability of water use cannot yet be incorporated in control mechanisms for virtual water flows in global food trade. New observational capacities (e.g. the COPERNICUS sensors) and model approaches can now be applied to bridge the gap between local and global scales by quantifying and investigating water flows in detail. This paper presents the outline, basic concept and first results of the ViWA-Initiative, where operational Earth Observation, physically-based growth modelling and economic trade modelling are combined to provide a continuous monitoring system for global virtual water flows in the agricultural commodity chain.