Impacts of Climate and Land-use Change on Water Quality, Floods, and Droughts for Catchments in Northern England
Date:
Sim Reaney, Ivo Pink and Aaron Neill
Climate and land-use changes are projected to significantly affect the hydrological functioning of catchment systems, influencing the frequency of flood and drought events, the dominant hydrological pathways, and the conditions for biogeochemical processes. These changes in the landscape will alter the magnitude and timing of sediment and nutrient exports from the landscape into freshwater and marine systems, potentially significantly affecting ecological health and associated ecosystem services. To assess potential changes, we have modelled 10,000 km² of river catchments in Yorkshire, England, encompassing agricultural, moorland, and urban areas, using the HYPE model. This model has been applied at the 0.5 km² scale to provide a detailed representation of soil type, topography, and land cover. The model was validated using 20 years of historical data within the GLUE uncertainty framework, yielding an ensemble of 25 model parameter sets. The future scenarios are based on the 12-member ensemble from the UKCP18 2.2km convection-permitting Regional Climate Model under the RCP8.5 global emissions scenarios. The combined uncertainty representation yielded a set of 300 parameter and climate-model simulations. This ensemble was applied to land-use change projections from the CRAFTY-GB dataset for the SSP1—Sustainability, SSP2—Middle-of-the-road, and SSP5—Fossil-fuelled development scenarios, from 2020 to 2080. The results project that the hydrological extremes (both low and high flows) tend to become more pronounced. Furthermore, water temperatures are projected to increase by up to 5 ℃, particularly during low-flow periods in the summer months (June – September), with significant potential impacts on fish habitats. Hydrological and water-temperature changes are driven by projected climatic changes. However, land-use scenarios can significantly affect suspended-sediment and nutrient concentrations, with this effect varying across catchments. The results have been embedded in a web-based dashboard to enable stakeholders to easily access the dataset of interest to them.odwater generation. When combined, they can provide effective measures for developing flood risk management strategies.
Presented at AOGS 2026, Fukuoka, Japan