We have established a soil moisture profile monitoring network in the Raam
region in the Netherlands. This region faces water shortages during summers
and excess of water during winters and after extreme precipitation events.
Water management can benefit from reliable information on the soil water
availability and water storing capacity in the unsaturated zone. In situ
measurements provide a direct source of information on which water managers
can base their decisions. Moreover, these measurements are commonly used as a
reference for the calibration and validation of soil moisture content products
derived from earth observations or obtained by model simulations. Distributed
over the Raam region, we have equipped 14 agricultural fields and 1 natural
grass field with soil moisture and soil temperature monitoring
instrumentation, consisting of Decagon 5TM sensors installed at depths of
5, 10, 20, 40 and 80 cm. In total, 12 stations are located within the
Raam catchment (catchment area of 223 km
2), and 5 of these stations are
located within the closed sub-catchment Hooge Raam (catchment area
of 41 km
2). Soil-specific calibration functions that have been developed
for the 5TM sensors under laboratory conditions lead to an accuracy of
0.02 m
3 m
−3. The first set of measurements has been retrieved for
the period 5 April 2016–4 April 2017. In this paper, we describe the Raam
monitoring network and instrumentation, the soil-specific calibration of the
sensors, the first year of measurements, and additional measurements (soil
temperature, phreatic groundwater levels and meteorological data) and
information (elevation, soil physical characteristics, land cover and a
geohydrological model) available for performing scientific research. The data
are available at
https://doi.org/10.4121/uuid:dc364e97-d44a-403f-82a7-121902deeb56.