Prospective life cycle assessment of viticulture under climate change scenarios, application on two case studies in France.

Viticulture needs to satisfy consumers' demands for environmentally sound grape and wine production while envisaging adaptation options to diminish the impacts of projected climate change on future productivity. However, the impact of climate change and the adoption of adaptation levers on the environmental impacts of future viticulture have not been assessed. This study evaluates the environmental performance of grape production in two French vineyards, one located in the Loire Valley and another in Languedoc-Roussillon, under two climate change scenarios. First, the effect of climate-induced yield change on the environmental impacts of future viticulture was assessed based on grape yield and climate data sets. Second, besides the climate-induced yield change, this study accounted for the impacts of extreme weather events on grape yield and the implementation of adaptation levers based on the future probability and potential yield loss due to extreme events. The life cycle assessment (LCA) results associated with climate-induced yield change led to opposite conclusions for the two vineyards of the case study. While the carbon footprint of the vineyard from Languedoc-Roussillon is projected to increase by 29 % by the end of the century under the high emissions scenario (SSP5-8.5), the corresponding footprint is projected to decrease in the vineyard from the Loire Valley by approximately 10 %. However, when including the effect of extreme events and adaptation options, the life cycle environmental impacts of grape production are projected to drastically increase for both vineyards. For instance, under the SSP5-8.5 scenario, the carbon footprint for the vineyard of Languedoc-Roussillon is projected to increase fourfold compared to the current footprint, while it will rise threefold for the vineyard from the Loire Valley. The obtained LCA results emphasized the need to account for the impact of both climate change and extreme events on grape production under future climate change scenarios.

Generating environmental sampling and testing data for micro- and nanoplastics for use in life cycle impact assessment.

Ongoing efforts focus on quantifying plastic pollution and describing and estimating the related magnitude of exposure and impacts on human and environmental health. Data gathered during such work usually follows a receptor perspective. However, Life Cycle Assessment (LCA) represents an emitter perspective. This study examines existing data gathering and reporting approaches for field and laboratory studies on micro- and nanoplastics (MNPs) exposure and effects relevant to LCA data inputs. The outcomes indicate that receptor perspective approaches do not typically provide suitable or sufficiently harmonised data. Improved design is needed in the sampling, testing and recording of results using harmonised, validated and comparable methods, with more comprehensive reporting of relevant data. We propose a three-level set of requirements for data recording and reporting to increase the potential for LCA studies and models to utilise data gathered in receptor-oriented studies. We show for which purpose such data can be used as inputs to LCA, particularly in life cycle impact assessment (LCIA) methods. Implementing these requirements will facilitate proper integration of the potential environmental impacts of plastic losses from human activity (e.g. litter) into LCA. Then, the impacts of plastic emissions can eventually be connected and compared with other environmental issues related to anthropogenic activities.

Transport mechanisms and fate of microplastics in estuarine compartments: A review.

Despite the importance of estuaries as transition zones between freshwater and marine compartments, their role in the transport of microplastics is still unclear. This review analyzes the findings pertaining to the transport mechanisms and other factors that influence the fate of microplastics in estuaries. It was found that the concentration of microplastics temporally varies under daily tides, monthly tides, and seasonal flows. Moreover, it spatially varies due to density effects, biofouling, aggregation, and salinity. Wind direction and intensity impact the spatiotemporal distribution of microplastics in the water column. Some of these processes transport microplastics to the estuarine sediments. Thereafter, microplastics are prone to resuspension by turbulence and bioturbation. Hence, estuaries act as temporary sinks that retain microplastics before being flushed to the ocean. Finally, a review of highly plastic-emitting rivers shows differences in the factors affecting the transport mechanisms of microplastics, which calls for regionalization when modelling their fate henceforward.

Evaluation of sector-specific AWARE characterization factors for water scarcity footprint of electricity generation.

Life Cycle Impact Assessment (LCIA) links the emissions and resource abstractions of a product system or process to potential impacts on the environment through characterization factors (CF). For regionalized impact categories like water-use, the regional CFs can vary over several orders of magnitude within the same country. The aggregated country-level CF, often used in LCIA, represents an average of local CF weighted by the local water consumption of all (or most) human water use including water use by all (or most) economic sectors. There is, however, great variability in spatio-temporal distribution of human water consumption across different industries. This study provides industry-specific water-use CFs for the electricity sector across the US. Our analysis shows that for electricity generation, the use of all-sector aggregated water-use CF would lead to an underestimation of impact scores compared to industry-specific CFs, by two folds. Even within the electricity sector, for two of the major subsectors, electricity based on natural gas and hydroelectricity, the country-level CFs can be significantly different due to the geographic distribution of powerplants. Our findings signify that the use of industry-specific CF can have a high influence in LCIA, especially for impact categories, such as water-use, with great spatio-temporal heterogeneity.

Defining freshwater as a natural resource: A framework linking water use to the area of protection natural resources.

PURPOSE: While many examples have shown unsustainable use of freshwater resources, existing LCIA methods for water use do not comprehensively address impacts to natural resources for future generations. This framework aims to (1) define freshwater resource as an item to protect within the Area of Protection (AoP) natural resources, (2) identify relevant impact pathways affecting freshwater resources, and (3) outline methodological choices for impact characterization model development. METHOD: Considering the current scope of the AoP natural resources, the complex nature of freshwater resources and its important dimensions to safeguard safe future supply, a definition of freshwater resource is proposed, including water quality aspects. In order to clearly define what is to be protected, the freshwater resource is put in perspective through the lens of the three main safeguard subjects defined by Dewulf et al. (2015). In addition, an extensive literature review identifies a wide range of possible impact pathways to freshwater resources, establishing the link between different inventory elementary flows (water consumption, emissions and land use) and their potential to cause long-term freshwater depletion or degradation. RESULTS AND DISCUSSION: Freshwater as a resource has a particular status in LCA resource assessment. First, it exists in the form of three types of resources: flow, fund, or stock. Then, in addition to being a resource for human economic activities (e.g. hydropower), it is above all a non-substitutable support for life that can be affected by both consumption (source function) and pollution (sink function). Therefore, both types of elementary flows (water consumption and emissions) should be linked to a damage indicator for freshwater as a resource. Land use is also identified as a potential stressor to freshwater resources by altering runoff, infiltration and erosion processes as well as evapotranspiration. It is suggested to use the concept of recovery period to operationalize this framework: when the recovery period lasts longer than a given period of time, impacts are considered to be irreversible and fall into the concern of freshwater resources protection (i.e. affecting future generations), while short-term impacts effect the AoP ecosystem quality and human health directly. It is shown that it is relevant to include this concept in the impact assessment stage in order to discriminate the long-term from the short-term impacts, as some dynamic fate models already do. CONCLUSION: This framework provides a solid basis for the consistent development of future LCIA methods for freshwater resources, thereby capturing the potential long-term impacts that could warn decision makers about potential safe water supply issues in the future.

A Multimedia Hydrological Fate Modeling Framework To Assess Water Consumption Impacts in Life Cycle Assessment.

Many new methods have recently been developed to address environmental consequences of water consumption in life cycle assessment (LCA). However, such methods can only partially be compared and combined, because their modeling structure and metrics are inconsistent. Moreover, they focus on specific water sources (e.g., river) and miss description of transport flows between water compartments (e.g., from river to atmosphere via evaporation) and regions (e.g., atmospheric advection). Consequently, they provide a partial regard of the local and global hydrological cycle and derived impacts on the environment. This paper proposes consensus-based guidelines for a harmonized development of the next generation of water consumption LCA indicators, with a focus on consequences of water consumption on ecosystem quality. To include the consideration of the multimedia water fate between compartments of the water cycle, we provide spatial regionalization and temporal specification guidance. The principles and recommendations of the paper are applied to an illustrative case study. The guidelines set the basis of a more accurate, novel way of modeling water consumption impacts in LCA. The environmental relevance of this LCA impact category will improve, yet much research is needed to make the guidelines operational.

Understanding the LCA and ISO water footprint: A response to Hoekstra (2016) "A critique on the water-scarcity weighted water footprint in LCA".

Water footprinting has emerged as an important approach to assess water use related effects from consumption of goods and services. Assessment methods are proposed by two different communities, the Water Footprint Network (WFN) and the Life Cycle Assessment (LCA) community. The proposed methods are broadly similar and encompass both the computation of water use and its impacts, but differ in communication of a water footprint result. In this paper, we explain the role and goal of LCA and ISO-compatible water footprinting and resolve the six issues raised by Hoekstra (2016) in "A critique on the water-scarcity weighted water footprint in LCA". By clarifying the concerns, we identify both the overlapping goals in the WFN and LCA water footprint assessments and discrepancies between them. The main differing perspective between the WFN and LCA-based approach seems to relate to the fact that LCA aims to account for environmental impacts, while the WFN aims to account for water productivity of global fresh water as a limited resource. We conclude that there is potential to use synergies in research for the two approaches and highlight the need for proper declaration of the methods applied.

Regional characterization of freshwater Use in LCA: modeling direct impacts on human health.

Life cycle assessment (LCA) is a methodology that quantifies potential environmental impacts for comparative purposes in a decision-making context. While potential environmental impacts from pollutant emissions into water are characterized in LCA, impacts from water unavailability are not yet fully quantified. Water use can make the resource unavailable to other users by displacement or quality degradation. A reduction in water availability to human users can potentially affect human health. If financial resources are available, there can be adaptations that may, in turn, shift the environmental burdens to other life cycle stages and impact categories. This paper proposes a model to evaluate these potential impacts in an LCA context. It considers the water that is withdrawn and released, its quality and scarcity in order to evaluate the loss of functionality associated with water uses. Regionalized results are presented for impacts on human health for two modeling approaches regarding affected users, including or not domestic uses, and expressed in disability-adjusted life years (DALY). A consumption and quality based scarcity indicator is also proposed as a midpoint. An illustrative example is presented for the production of corrugated board with different effluents, demonstrating the importance of considering quality, process effluents and the difference between the modeling approaches.