The water footprint of Switzerland

Usually, countries do not consider the external water footprint of national consumption, which is related to imported water-intensive commodities, in their national water policies. In order to support a broader sort of analysis and better inform decision-making, the traditional production perspective in national water policy should be supplemented with a consumption perspective. Because many consumer goods are imported, a responsible and fair national water policy should include an international dimension. This report focusses on Switzerland. The background of the study is the recognition that there is a relation between the import of water-intensive goods to Switzerland and their impacts on water systems elsewhere in the world. Many of the goods consumed in Switzerland are not produced domestically, but abroad. Some goods, most in particular agriculture-based products, require a lot of water during production. These water-intensive production processes are often accompanied by impacts on the water systems at the various locations where the production processes take place. The impacts vary from reduced river water flows, declined lake levels and groundwater tables and increased salt intrusion in coastal areas to pollution of freshwater bodies. The objective of this study is to carry out a water footprint assessment for Switzerland from a consumption perspective. The assessment focuses on the analysis of the external water footprint of Swiss consumption, to get a complete picture of how national consumption translates to water use, not only in Switzerland, but also abroad, and to assess Swiss dependency on external water resources and the sustainability of imports. The study quantifies and maps the external water footprint of Switzerland, differentiating between agricultural and industrial commodities, and shows how the blue water footprint of Swiss consumption contributes to blue water scarcity in specific river basins and which products are responsible herein. The total water footprint of national consumption of Switzerland is an average 11 billion m3 per year for the period 1996-2005, which is 1528 m3 per year or approximately 4120 litre per day per Swiss citizen. About 68% of this total is ‘green’, 25% ‘grey’ and 7% ‘blue’. Consumption of agricultural commodities makes up the bulk of Switzerland’s water footprint, accounting for 81% of the total. Industrial commodities account for 17%; the remaining 2% relates to domestic water supply. Most of the water footprint of Swiss consumption (82%) lies outside Switzerland. About 34% of the blue water footprint of Swiss consumption is in river basins that experience moderate to severe water scarcity during at least one month in a year. The priority basins are located in France (Garonne, Loire, Escaut and Seine), Italy (Po), Central Asia (Aral Sea basin), the USA (Mississippi), India (Ganges, Krishna, Godavari, Tapti, Mahi, Cauvery and Penner), Pakistan (Indus), Spain (Guadalquivir, Guadiana, and Tejo), Middle East (Tigris and Euphrates), China (Huang He, Yongding He, Mekong, Huai He and Tarim), West Africa (Nile, Tana) and Côte d'Ivoire (Sassandra). Cotton, rice, sugar cane, grape, sorghum, maize, soybean, sunflower, citrus and coffee are identified as priority products, giving significant contributions to the blue water scarcity in the selected priority basins. Especially cotton, rice and sugar cane give an important contribution to the blue water footprint in many of these basins

A Simplified Water Accounting Procedure to Assess Climate Change Impact on Water Resources for Agriculture across Different European River Basins

[EN] European agriculture and water policies require accurate information on climate change impacts on available water resources. Water accounting, that is a standardized documentation of data on water resources, is a useful tool to provide this information. Pan-European data on climate impacts do not recognize local anthropogenic interventions in the water cycle. Most European river basins have a specific toolset that is understood and used by local experts and stakeholders. However, these local tools are not versatile. Thus, there is a need for a common approach that can be understood by multi-fold users to quantify impact indicators based on local data and that can be used to synthesize information at the European level. Then, policies can be designed with the confidence that underlying data are backed-up by local context and expert knowledge. This work presents a simplified water accounting framework that allows for a standardized examination of climate impacts on water resource availability and use across multiple basins. The framework is applied to five different river basins across Europe. Several indicators are extracted that explicitly describe green water fluxes versus blue water fluxes and impacts on agriculture. The examples show that a simplified water accounting framework can be used to synthesize basin-level information on climate change impacts which can support policymaking on climate adaptation, water resources and agriculture.This research was funded by Horizon 2020 IMPREX project, grant number 641811Hunink, J.; Simons, G.; Suárez-Almiñana, S.; Solera Solera, A.; Andreu Álvarez, J.; Giuliani, M.; Zamberletti, P.... (2019). A Simplified Water Accounting Procedure to Assess Climate Change Impact on Water Resources for Agriculture across Different European River Basins. 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Environmental footprint family to address local to planetary sustainability and deliver on the SDGs

peer-reviewedThe number of publications on environmental footprint indicators has been growing rapidly, but with limited efforts to integrate different footprints into a coherent framework. Such integration is important for comprehensive understanding of environmental issues, policy formulation and assessment of trade-offs between different environmental concerns. Here, we systematize published footprint studies and define a family of footprints that can be used for the assessment of environmental sustainability. We identify overlaps between different footprints and analyse how they relate to the nine planetary boundaries and visualize the crucial information they provide for local and planetary sustainability. In addition, we assess how the footprint family delivers on measuring progress towards Sustainable Development Goals (SDGs), considering its ability to quantify environmental pressures along the supply chain and relating them to the water-energy-food-ecosystem (WEFE) nexus and ecosystem services. We argue that the footprint family is a flexible framework where particular members can be included or excluded according to the context or area of concern. Our paper is based upon a recent workshop bringing together global leading experts on existing environmental footprint indicators

Climate Impact Storylines for Assessing Socio-Economic Responses to Remote Events

Complex interactions involving climatic features, socio-economic vulnerability or responses, and long impact transmissions are associated with substantial uncertainty. Physical climate storylines are proposed as approach to explore complex impact transmission pathways and possible alternative unfolding of event cascades under future climate conditions. These storylines are particularly useful for climate risk assessment for complex domains, including event cascades crossing multiple disciplinary or geographical borders. For an effective role in climate risks assessments, practical guidelines are needed to consistently develop and interpret the storyline event analyses.This paper elaborates on the suitability of physical climate storyline approaches involving climate event induced shocks propagating into societal impacts. It proposes a set of common elements to construct the event storylines. In addition, criteria for their application for climate risk assessment are given, referring to the need for storylines to be physically plausible, relevant for the specific context, and risk-informative.Six examples of varying scope and complexity are presented, all involving the potential climate change impact on European socio-economic sectors induced by remote climate change features occurring far outside the geographical domain of the European mainland. The storyline examples illustrate the application of the proposed storyline components and evaluates the suitability criteria defined in this paper. It thereby contributes to the standardization of the design and application of event-based climate storyline approaches

Governance of globalized water resources: the application of the water footprint to inform corporate strategy and government policy

Managing the water footprint of humanity is something in which both governments and businesses have a key role. The actual reduction of humanity's water footprint depends on the combination of what governments, businesses and consumers do and how their different actions reinforce (or counteract) one another. Therefore, we need improved understanding of how water footprint reduction strategies by governments on the one hand and companies on the other hand can reinforce or counteract each other in achieving actual reduction of humanity's water footprint. The objective of this thesis is to understand how the water footprint concept can be used as a tool to inform governments and businesses about sustainable, efficient and equitable water use and allocation. This study alternately takes a governmental and a corporate perspective, because both actors have a significant role in mitigating the water footprint of humanity and there is a strong interaction between the roles and responsibilities of both actors

European Water Footprint Scenarios for 2050

This study develops water footprint scenarios for Europe for 2050, at the country level, based on projections regarding population and economic growth, production and trade patterns, consumption patterns (diets and bioenergy use) and technological development. The objective is to estimate possible future changes in the green, blue and grey water footprint (WF) of production and consumption, to analyze the main drivers of projected changes and to assess Europe's future dependence on water resources elsewhere in the world. We develop four scenarios, considering globalization versus regional self-sufficiency, and development driven by economic objectives versus development driven by social and environmental objectives. The study shows that the most critical driver of change affecting Europe's future WF is the consumption pattern. The WFs of both production and consumption in Western Europe increase under scenarios with high meat consumption and decrease with low-meat scenarios. Besides, additional water demands from increasing biofuel needs will put further pressure on European water resources. The European countries with a large ratio of external to total WF of consumption in 2000 decrease their dependencies on foreign water resources in 205

Water footprint scenarios for 2050: A global analysis

This study develops water footprint scenarios for 2050 based on a number of drivers of change: population growth, economic growth, production/trade pattern, consumption pattern (dietary change, bioenergy use) and technological development. The objective the study is to understand the changes in the water footprint (WF) of production and consumption for possible futures by region and to elaborate the main drivers of this change. In addition, we assess virtual water flows between the regions of the world to show dependencies of regions on water resources in other regions under different possible futures. We constructed four scenarios, along two axes, representing two key dimensions of uncertainty: globalization versus regional selfsufficiency, and economy-driven development versus development driven by social and environmental objectives. The study shows how different drivers will change the level of water consumption and pollution globally in 2050. The presented scenarios can form a basis for a further assessment of how humanity can mitigate future freshwater scarcity. We showed with this study that reducing humanity's water footprint to sustainable levels is possible even with increasing populations, provided that consumption patterns change. This study can help to guide corrective policies at both national and international levels, and to set priorities for the years ahead in order to achieve sustainable and equitable use of the world's fresh water resource