As technology progresses, satellites increasingly offer a reliable source of spatially distributed information on a variety of environmental variables. By using the reflective properties of the earth’s surface and atmosphere, it is possible to monitor (among others) vegetative cover, rainfall, snow cover, land surface temperature and actual evapotranspiration through time. Sensors like Landsat ETM, MODIS, NPP VIIRS and Sentinel offer a range of options on different spatial and temporal scales. FutureWater makes use of open-access datasets like these in consultancy studies, for operational decision support systems, and for feeding, calibrating and validating hydrological models.
Remote sensing in consultancy studies
Satellites now provide an archive of imagery that covers multiple decades. These extensive historical records allow us to identify trends and spatial patterns in different factors associated with water resource management, such as water supply, water consumption and crop growth. We analyze these trends and patterns to support policy makers in identifying appropriate measures at different locations in their management area.
Example: FutureWater applied a number of satellite-derived indices for analyzing historical drought occurrence and impacts in the Mekong River Basin. Ultimately, general drought risk maps were constructed to identify locations highly vulnerable to drought events (Go to project).
Remote sensing in operational decision support systems
A number of satellites pass over quite frequently, making their data especially useful for operational decision support systems. We collect these data as soon as it comes available, process it using our models, and disseminate the resulting information to the end user of the system. Examples of end users of such systems include water boards, farmers and hydropower companies. Up-to-date satellite-derived images provide insight in the actual conditions related to water resources and vegetation, without having to visit the field.
Example: FutureWater uses high-resolution satellite imagery to operationally monitor vegetation cover and soil water conditions in drought-affected nature areas in The Netherlands (Go to project).
Integrating satellite observations and simulation models
A smart combination of remote sensing and simulation modeling provides an integrated outlook on historical, current and future water availability. Typical examples of satellite-derived input parameters to simulation models are rainfall and vegetation cover. Remotely sensed information on e.g. soil moisture and evapotranspiration can be used to calibrate and/or validate hydrological models.
Remote sensing is by definition a method that can only provide information on the past situation. However, governments, basin authorities, farmers and hydropower companies are particularly interested in anticipating on future events by taking timely and targeted measures. Feeding hydrological models with the most recent satellite images in an operational context allows the construction of short-term forecast based on the actual current conditions.
Example: FutureWater often uses satellite imagery as an input to hydrological models, or for calibration and validation purposes. This example illustrates the usage of remotely sensed evapotranspiration measurements to validate a hydrological simulation model designed to predict inflow to hydropower reservoirs (Go to project).