Challenge 3: Linking water demand and groundwater dynamics

Challenge 3 focuses on the interactions between multi-year droughts and natural ecosystems while also considering the role of human water demand. Including human-water interactions with multi-year droughts is critical to identifying their impact on drought severity and duration. The use of a groundwater model (GM-GLOB1k) will help determine the drought duration resulting in long-term groundwater impacts. It has already been observed that during multi-year droughts, there is a strong decline in groundwater levels that can take several years to decades to recover, even when precipitation rates return to normal or below normal. Therefore, GM-GLOB1k will also be utilised to compute the time required for drought recovery and assess the effect of human interventions on these recovery periods.

This is critical as the impacts of multi-year droughts are becoming more severe. For example, farmers often lack the financial resources to survive multi-year droughts due to their persistent impacts, leading to the abandonment of agricultural practices. Finally, when recovery times are reduced to below a stable limit, groundwater abstraction can become unsustainable, especially in regions with high abstraction rates. Therefore, the impact of groundwater abstraction on multi-year drought intensity and recovery potential, both for historic storylines and as part of a climate change assessment, will be evaluated through the GM-GLOB1k modelling system.