Attributing climate drivers to nitrate lag times in Austrian groundwater

The project investigates the influence of climate variability and climate change on nitrate dynamics in groundwater across Austria. Its objective is to quantify the interactions between climate, land use, agricultural management and hydrogeological conditions, and to determine the contribution of climatic drivers to groundwater nitrate contamination. Particular emphasis is placed on identifying delayed system responses (legacy effects) and assessing how droughts, heavy precipitation and compound climate extremes affect nitrate mobilisation and transport. The study is based on a unique nationwide dataset comprising long-term groundwater monitoring records, high-resolution climate data and spatial land-use information. An integrated methodological framework combining climate indices, statistical analyses and machine learning techniques will be developed to identify the relationships between climatic drivers and groundwater nitrate concentrations and to predict future changes under different climate scenarios. The project addresses a critical knowledge gap regarding the role of climate in controlling groundwater quality. It will develop predictive models, quantify time lags between land-surface drivers and groundwater responses, and classify groundwater bodies according to their sensitivity to climatic stressors. The results will be translated into spatial vulnerability maps identifying areas that are particularly susceptible to climate-induced changes in groundwater quality. The project will provide a scientific basis for assessing climate-related risks to groundwater quality and for prioritising groundwater monitoring and management measures. The main target groups are water authorities, water resource managers, drinking water suppliers and the scientific community, providing evidence-based decision support for the long-term protection and sustainable management of groundwater resources.