climate change on UAE - Stockholm Environment Institute-US Center

total water demand estimate at about 7,000
Mm 3 , which is more than double the current
estimate, with nearly all the demand growth
occurring in the M&I sector. Comparing the
two MOR Scenarios (with and without <strong>climate</strong>
<strong>change</strong>) suggests that warming leads to a
marginal increase in total water demand by
2050 of less than 5%.
Not surprising, all Scenarios suggest that
future population, per-capita water use, and
future decisions about outdoor irrigation of
the agriculture, forestry and amenity sectors
will most likely dominate total water demand.
Climate <strong>change</strong>, manifesting itself primarily as
<strong>climate</strong> warming, will likely increase demand
by less than 5%, which is small relative to the
<strong>change</strong>s from the other factors. The water
demand estimates just presented are based on
the assumption that there is water available
to meet those demands, with the demands
computed from assumptions that include
population, per-capita use, <strong>climate</strong>, and the
irrigation strategy for each outdoor use. Since
WEAP tracks both the demand and supply
sides of the water accounting ledger, we now
investigate these Scenarios from the supply
side of the equation.
5.2. Water Supply
In WEAP water demand is computed as a total
requirement based on the given assumptions,
but this requirement does not necessarily
reflect the amount of water delivered to meet
those demands. To supply the computed water
needs, water infrastructure is represented in
the model that includes desalinization plants,
pumps, treatment facilities, groundwater
aquifers with a assumed capacity, a distribution
network, etc. Certainly in the UAE, water supply
capacity and availability constrains the amount
of water delivered to the various end-uses.
Quantifying this “unmet demand” is of course
subjective. For example, in the agriculture,
amenity and forestry sector, the vegetation
and crops that have been planted could most
certainly use more water to be healthier and
more vibrant, but in the hyper-arid environment
of the ADE, it makes sense to deficit irrigate,
as water is simply to precious (and expensive).
In WEAP, the difference between the computed
“demand” and the model based allocation of
supply to meet those demands (e.g. “Supply
Delivered”) is referred to as “Unmet Demand”
or the supply deficit (Figure ‎5‐3). Since the
M&I sector is nearly 100% reliant on desalinized
Impacts, Vulnerability & Adaptation for
Water Resources in Abu Dhabi
Future Water Supplies
Figure ‎5‐3. Supply allocation for Optimistic Scenario with Adaptation-
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