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What are the units and what do they mean?
A m³-world eq. (obtained from the multiplication of the factor in m³ world-eq./m³ consumed with the inventory in m³ consumed) represents a cubic meter consumed on average in the world. The average refers to a consumption-weighted average, and hence represents the locations where water is currently consumed. This is therefore a comparative unit, representing the “average cubic meter consumed in the world”.
Why are there different factors? What is the difference between “agri” and “non-agri”? Is irrigation water consumption included in both?
At the native scale (monthly values on (sub)basin scale), there is only one AWARE factor, calculated with the equation described in the documentation. The calculation of the native CF is always the same, and always includes all human water consumption. When this factor has to be provided at different scales, such as annual or country scale, the factors must be aggregated. The difference between “agri” and “non-agri” only lies in the way they are aggregated, reflecting better the temporal or geographical patterns of consumption for agricultural or non agricultural activities, if the exact month and/or watershed is not known. In AWARE, “agri” and “non-agri” are sometimes referred to as “irri” and “non-irri”, since the water consuming activity implied by “agricultural” is irrigation. For an example of when to use the agri factor, see the how-to.
What does “unspecified” or “unknown” mean if used to describe an AWARE factor?
As described in the previous answer, it is possible to aggregate native scale AWARE factors to other scales. While distinguishing the categories agri/irri and non-agri/non-irri in these aggregated factors comes handy in situations where the type of the water consumption under study is known, there are situations where a certain amount of water consumption is known in m³ but cannot be fully attributed to one of the two mentioned categories. The aggregated AWARE factors for “unspecified” or “unknown” types of water consumption take this into account by not distinguishing between agri and non-agri but respecting temporal and geographical patterns of all types of human water consumption at once.
Is groundwater availability included?
In WaterGAP, only the renewable part of groundwater storage is considered, which is groundwater recharge. Groundwater recharge is calculated as a fraction of runoff from land but additional recharge from irrigated land is considered, too. More information can be found in Müller Schmied et al (2014) and Döll & Fiedler (2008). Fossil Ground water is not included.
How do I use the AWARE factors?
The local AWARE factor is meant to be multiplied with the local water consumption inventory. Water consumption is defined in Bayart et al. (2010) as a use of water where release into the original watershed does not occur because of evaporation, product integration, or discharge into different watersheds or the sea. Please also see the AWARE How-To.
Can I use the AWARE factors to calculate the water footprint of a nation?
The AWARE factors are developed for LCA purposes, and hence for “marginal” water consumptions, i.e. water consumption that does not change the background level of water availability significantly. For large-scale assessment, a different version of AWARE factors can be used. Please consult the “non-marginal AWARE” section for this application.
Is reused/desalinated water included?
Water consumption is calculated in WaterGAP as the difference between water withdrawals and return flows. Water reuse lowers the amount of water abstracted in a region, and also reduces return flows. It is therefore indirectly considered in the calculation, but not included in the definition of water consumption which refers to direct freshwater consumption. The same applies for desalinated water.
Can I reuse the AWARE factors and how do I give appropriate credit?
There is no restriction in using the AWARE factors in your studies and environmental footprint methodologies. The only requirement is a proper citation to the work of the WULCA group communicated in the 2018 publication: Boulay A-M, Bare J, Benini L, et al. (2018) The WULCA consensus characterization model for water scarcity footprints: assessing impacts of water consumption based on available water remaining (AWARE). Int J Life Cycle Assess 23:368–378.