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 and (sub)basin scale, there is only one AWARE factor, calculated with the equation described in the documentation. 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. The calculation of the native CF is always the same, and always includes all human water consumption.
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.
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.