The aim of the TEMBO-project is to set up cost-effective innovative sensor networks that can be financed by climate services built on top of these networks. Rainfall, soil moisture, river flow and bathymetry - these essential hydrological variables can be measured at less than 10% of current costs, using the new methods developped in the project. Reduced costs are necessary for a realistic business model for services through the Global Earth Observation System of Systems, or GEOSS. The EU-funded TEMBO Africa project will design cost-effective sensor networks (financed by climate services). Specifically, the project will raise technology readiness levels and improve the practical applicability of these methods. By directly linking sensors and new value-creating services, the project will ensure long-term financial sustainability. For the African market, in particular, the project will develop flood early warning systems, reservoir management and crop germination insurance services.