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Precise knowledge of the antenna pointing direction is a key facet to ensure the accuracy of observations from scanning weather radars. The sun is an often-used reference point to aid accurate alignment of weather radar systems and is particularly useful when observed as interference during normal scanning operations. In this study, we combine two online solar interference approaches to determine the pointing accuracy of an X-band mobile weather radar system deployed for 26 months in northern England (54.517°N, 3.615°W). During the deployment, several shifts in the tilt of the radar system are diagnosed between site visits. One extended period of time (>11 months) is shown to have a changing tilt that is independent of human intervention. To verify the corrections derived from this combined approach, quantitative precipitation estimates (QPEs) from the radar system are compared to surface observations: an approach that takes advantage of the variations in the magnitude of partial beam blockage corrections required due to tilting of the radar system close to mountainous terrain. The observed improvements in QPE performance after correction support the use of the derived tilt corrections for further applications using the corrected dataset. Finally, recommendations for future deployments are made, with particular focus on higher latitudes where solar interference spikes show more seasonality than those at mid-latitudes.

Ecosystem Service (ES) toolkits are increasingly used to quantify and visualize the benefits gained from Nature-based-solutions (NBS) but modules for hydrology are often absent, or if present they lack meaningful hydrological functionality or validation. This leads to gaps in the evidence base required by decision makers. To bridge the gap between such limitations and more complex hydrological models this paper presents a hydrologically based NBS model compatible with spatial ES toolkits. The approach ‘Adapted Nature-based-solutions Rational Method’ (ANaRM) is based on the Rational Method, widely used in hydrology. We apply this model to the city of Birmingham, England, to validate its performance and to analyse the effects of different NBS scenarios. The validated ANaRM model provided robust estimates of peak flow using design storm rainfall. It proved capable of simulating the hydrological effects of NBS such as land use change from urban to green, or installation of SuDS and ponds. Results suggest ponds are found most effective for achieving peak flow reduction in channels and are the best option for mitigating fluvial flooding downstream. Reduction in localised runoff and pluvial flooding is best achieved by converting impervious surfaces such as buildings, hardstanding and roads to green solutions such as green roofs, permeable pavements and greenspace. This paper highlights the importance of considering the spatial effects of urban NBS on hydrology, and that these can be captured with relatively simple modelling approaches such as ANaRM. Its ease of use means it suits any level of user looking to represent the flood mitigation aspect of NBS spatially and has high potential as part of any ES toolkit focused on representing the spatial effects of NBS on ecosystem services.

Cosmic-Ray Neutron Probes (CRNP) have found application in soil moisture (SM) estimation due to their conveniently large (>100 m) footprints. Here, we explore the possibility of using high-density polyethylene (HDPE) moderator to limit the field of view, and hence, the footprint of a SM sensor formed of 12 CRNP mounted on to a mobile robotic platform (Thorvald) for better in-field localization of moisture variation. Ultra Rapid Adaptable Neutron-Only Simulation neutron scattering simulations are used to show that 5 cm of additional HDPE moderator (used to shield the upper surface and sides of the detector) is sufficient to (a) reduce the footprint of the detector considerably, (b) approximately double the percentage of neutrons detected from within 5 m of the detector, and (c) does not affect the shape of the curve used to convert neutron counts into SM. Simulation and rover measurements for a transect crossing between grass and concrete additionally suggest that (d) SM changes can be sensed over a length scales of tens of meters or less (roughly an order of magnitude smaller than commonly used footprint distances), and (e) the additional moderator does not reduce the detected neutron count rate (and hence increase noise) as much as might be expected given the extent of the additional moderator. The detector with additional HDPE moderator was also used to conduct measurements on a stubble field over three weeks to test the rover system in measuring spatial and temporal SM variation.

The intensity of cosmic ray neutrons is inversely correlated with the amount of water present in the surrounding environment. This effect is already employed by around 50 neutron sensors in the COSMOS‐UK network to provide daily estimates of soil moisture across the UK. Here, these same sensors are used to automatically provide estimates of Snow Water Equivalent (SWE). Lying snow is typically ephemeral and of shallow depth for most parts of the UK. Moreover, soil moisture is usually high and variable, which acts to increase uncertainties in the SWE estimate. Nevertheless, even under such challenging conditions, both above ground and buried cosmic ray neutron sensors are still able to produce potentially useful SWE estimates. Triple collocation analysis suggests typical uncertainties of less than around 4mm under UK snow conditions.

Cosmic Ray Neutron Probes (CRNP) have found application in soil moisture estimation due to their conveniently large (>100 m) footprints. Here we explore the possibility of using high density polyethylene (HDPE) moderator to limit the field of view, and hence the footprint, of a soil moisture sensor formed of 12 CRNP mounted on to a mobile robotic platform (Thorvald) for better in-field localisation of moisture variation. URANOS neutron scattering simulations are used to show that 5 cm of additional HDPE moderator (used to shield the upper surface and sides of the detector) is sufficient to (i), reduce the footprint of the detector considerably, (ii) approximately double the percentage of neutrons detected from within 5 m of the detector, and (iii), does not affect the shape of the curve used to convert neutron counts into soil moisture. Simulation and rover measurements for a transect crossing between grass and concrete additionally suggest that (iv), soil moisture changes can be sensed over a length scales of tens of meters or less (roughly an order of magnitude smaller than commonly used footprint distances), and (v), the additional moderator does not reduce the detected neutron count rate (and hence increase noise) as much as might be expected given the extent of the additional moderator. The detector with additional HDPE moderator was also used to conduct measurements on a stubble field over three weeks to test the rover system in measuring spatial and temporal soil moisture variation.