Our Research
BLOSM: Boron-based Large scale Observation of Soil Moisture
Measuring soil moisture in the field at a scale comparable to that of satellite pixels or model raster cells is a central hydrological problem for calibration and validation. Using the standard gravimetric method, this involves taking many (100-1000) samples, which can only be achieved through expensive field campaigns. There is one way to measure soil moisture at a scale of about 30 hectares and that is, somewhat surprisingly, by measuring fast and slow neutrons at a point.
The GNSS navigation system for meteorology
GPS/GNSS sensors located at fixed positions can be exploited to derive measures of the atmospheric water vapor content with accuracies comparable to conventional instruments. Existing widespread networks of fixed GNSS stations could provide currently unavailable meteorological information to enhance the prediction of heavy rainfall. This innovative potential use of GNSS can be further boosted by the exploitation of low-cost sensors, made available thanks to technological advancements fostered by mass market applications of GPS/GNSS for navigation
New sensitivity studies for better heavy rainfall forecasts
Numerical Weather Prediction (NWP) models rely on numerous parameterizations to represent atmospheric processes that cannot be explicitly quantified because they happen on very small scales, such as droplet formation. However, these parameterizations are critical for a correct forecast of heavy rainfall. New sensitivity experiments have highlighted how important the mixing in the lower atmosphere is to correctly reproduce heavy rainfall dynamics
A fast and robust algorithm for the generation of SAR atmospheric water vapor maps
SAR images from the Copernicus Sentinel 1 satellite mission can be used to derive the distribution of atmospheric water vapor over large areas at a very high spatial resolution. A novel algorithm was developed and implemented to extract such snapshots for meteorological applications
Optimization tool for monitoring networks using satellite rainfall estimates
Monitoring networks set up by national weather services often follow generalized guidelines for instrument density. The World Meteorological Organization as well as the TAHMO initiative suggest station densities depending on the geographical setting. Especially in Africa, optimal densities are often not met, as a result of management issues but to a large degree in available resources required to install, operate and maintain dense monitoring networks. In such context of resource scarcity, knowledge of where and when additional monitoring adds the highest value not only improves data quality but also assists in planning networks more efficiently.
VegMon: Smartphone-assisted citizen sensing for vegetation monitoring
The VegMon app is based on the ODK platform. Using an interface, users can enter variables such as crop type through selection choices, photographs, GPS coordinates, as well as dates for planting and harvesting through calendar functions as well as manually measured plant heights and text comments. The VegMon app can be used by citizen scientists to monitor crop status.
Mapping flooding hotspots
Floodplains that experience frequent floods, such as Narok town (Kenya), require the use of flood maps as a way to inculcate a flood forecasting system in the municipality. Satellite observations can record the river basin and terrain characteristics, but are too infrequent and coarse-grained to identify flooding hotspots. Eyes on the ground are needed to complete the picture.
Drones for monitoring crop performance and water requirement
Farmers like to know how their crops are performing and how much water they require. Especially when little water is available and farmers must apply their water as efficiently as possible. With the Triangle method and using a blended satellite data and drone imagery approach, FutureWater developed a field-scale dryness index and crop evaporation product. This product is based on a relatively simple method and requires only few data inputs. The product can be produced quickly in data scarce regions and can be used to inform farmers about the relative moisture status of their field and water use requirements of their crops
Local temperature footprints improve Surface Energy Budget estimation
Satellites measure heat flux instantaneously as they pass over an area. Such instantaneous measurements (no more than the blink of an eye) poorly represent the daily average if variability in heat flux is high, as is the case in much of Africa. By combining Distributed Temperature Sensing and drone-based thermal measurements, we are able to get a detailed picture of variability in temperature and energy fluxes at the ground surface
