Towards an operational irrigation management system for Sweden with a water-food-energy nexus perspective

Pietro Elia Campana, Pablo Lastanao, Sebastian Zainali, Jie Zhang, Tomas Landelius, Forrest Melton

The 2018 drought in Sweden has triggered questions about climate adaptation and mitigation measures, especially in the agricultural sector, which suffered the most. This study applies a water-food-energy nexus modelling framework to evaluate drought impacts on irrigation and agriculture in Sweden using 2018 and 2019 as case studies. A previous water-food-energy nexus model was updated to facilitate an investigation of the benefits of data-driven irrigation scheduling as compared to existing irrigation guidelines. Moreover, the benefits of assimilating earth observation data in the crop model have been explored. The assimilation of leaf area index data from the Copernicus Global Land Service significantly improve the crop yield estimation as compared to default crop model parameters. The results show that the irrigation water productivities of the proposed model are measurably improved compared to conventional irrigation guidelines both in 2018 and in 2019. This is mostly due to the advantage of the proposed model in providing ETc-driven guidelines by using spatially-explicit data generated by mesoscale models from the Swedish Meteorological and Hydrological Institute. During a normal year, the proposed irrigation management system leads to significant water savings as compared to conventional irrigation guidelines. The modelling results show that temperature stress during the 2018 drought played a key role in the crop yield reduction, with yield reductions of up to 35%. In the context of the water-food-energy nexus, this motivates the implementation of new technologies to reduce water and temperature stress to mitigate likely negative effects of climate change. A visualization platform is developed using an open-source package for Google Earth® to help farmers and water and energy management agencies to better understand the connections between water and energy use and food production. This can be significant, especially during the occurrence of extreme events, but also to adapt to the negative effects of climate changes.