climate change on UAE - Stockholm Environment Institute-US Center

5. Results and
Discussion
The <strong>climate</strong> <strong>change</strong> assumptions for the three
main Scenarios are reflected in the previous
section in Table ‎4‐8, column 3. To remind you,
over the 1961-1990 baseline, the optimistic
<strong>climate</strong> <strong>change</strong> Scenario models a 1.7ºC warming
through 2050 and a 10 % increase in precipitation
for the optimistic Scenario; the pessimistic
Scenario models 2.7ºC warming through 2050
and a 20 % decrease in precipitation; while the
middle of the road (MOR) scenario models
2.2 o C warming through 2050 and a 5% increase
in precipitation. Many if not all of the Emirate’s
water shortage issues are demand driven, so we
have modeled adaptation strategies accordingly
while operating in the context of possible
<strong>climate</strong> <strong>change</strong>s by 2050.
5.1. Water Demand
Figure ‎5‐1 shows the total annual water demand
projections for all Scenarios through the end
of the simulation period (2050). The total
water demand is computed as a requirement,
but does not necessarily reflect the amount of
water supplied to meet those demands. Total
demand ranged from a low about 4,000 Mm 3 for
the Optimistic Scenario with adaptation (2.1)
to more than 18,000 Mm 3 for the Reference
Scenario, where population growth, per-capita
water use and amenity, forestry, and agriculture
water use patterns remain at current levels
through the full simulation period. While the
Reference Scenario is highly unlikely, it does
suggest an upper bound on future water needs
if there were no policy interventions.
The Optimistic Scenario (1) suggests a future
ADE population of nearly 7,000,000 by 2050,
requiring more than 5,000 Mm3 of water annually.
Despite reductions in per-capita water use
assumed in the Optimistic Scenarios, overall
water demand increases, driven by population
growth in the M&I sector. The Optimistic
Scenario with adaptation (1.1) suggests that
future total water demand could be kept near
current levels even with substantial population
growth. Reductions in water demand from the
three big outdoor users (agriculture, amenity
and forests) saves more than 1,000 Mm 3 per year
when compared to the Optimistic Scenarios
without these adaptations. Future <strong>climate</strong>
<strong>change</strong> in the Optimistic Scenarios results in
a relatively small increase in water demand of
about 3% by 2050 (1.2), and thus a comparison
of all three Optimistic Scenarios suggests that
societal adaptations to reducing water demand
will likely be more important than future
warming.
Impacts, Vulnerability & Adaptation for
Water Resources in Abu Dhabi
Scenarios of Future Annual Water Demand for the ADE
Figure ‎5‐1. Total annual water demand estimates for the nine Scenarios.
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