The research group succeeded to make the methodological jump to base crop water footprints on grid-specific application of FAO’s AquaCrop model at the global extent over a 50 year period. This constitutes a significant improvement over earlier global water footprint assessments using the CropWat model. The group is contributing results of the new ACEA (AquaCrop-EarthAlternatives) model to international global crop modelling intercomparison exercises (Jaegermeyer et al, 2021). Hogeboom er al (2020b) use the upgraded crop simulation as a basis for water productivity benchmarks.
As a new approach to interpret footprint assessments for policy making, benchmarking assessments are further developed, to put water footprints resulting from local practices in the context of general production efficiencies (with respect to water) under similar environmental conditions (Mekonnen et al., 2020). Accounting methods were enriched to separate out sustainable and unsustainable shares of environmental pressures (Mekonnen and Hoekstra, 2020).
Where both production- and consumption-based perspectives are common, a joint comparative consideration sheds often unconventional light on local water scarcity problems and solution strategies (Karandish et al, 2021).
Supply-chain approaches in water footprint accounting is expanded using multi-regional environmentally-extended input-output modelling. In particular for non-food commodities this enriches previous water footprint research. Supply-chain formulations from MRIO are useful in creating scenarios or assessing the internal consistency of scenarios on aspects of trade and economic structure. Current results include contributions to address methodological challenges in describing (durable) capital assets in accounting of environmental pressures (Ye et al., 2021a), and separation of virtual water flows embedded in trade of primary, intermediate and final consumption commodities (Ye et al., 2021b).
Methods to identify cultural or contextual aspects in SDG achievement were pursued (Zheng et al, 2021; Su et al., 2021), as they provide insights essential for upcoming scenario development in policy studies. Zheng et al (2021) show a large majority of SDG targets and a significant share of variations in SDG achievement to be linked to cultural traits. Those links are strikingly divergent across cultural traits and indicators, emphasizing the relevance of nuanced consideration of cultural aspects in research and policy design on SDG challenges. Su et al (2021) compare approaches of research into SDG linkages. Text analyses of countries’ self-studies, literature study on general linkages and correlation analyses at country resolution are analyzed with global coverage. Specific attention is given to identification of linkages as synergies and trade-offs, and to contextual factors, focusing on the water and land goals in SDG 2 and SDG 6.
Singling out effects of crop reallocation between countries, water scarcity reductions the most water-scarce countries were studied while keeping within constraints of current land and water use and only allowing for marginal changes (Chouchane et al, 2020a). An innovative mathematical optimization approach was implemented where differences between countries both in land and water productivities and in availability of land and water resource drive re-allocations, at global level and country resolution. The potential is found be very significant, with only moderate changes in, mostly, rainfed production needed to avoid severe water scarcity at national levels in the world.
