climate change on UAE - Stockholm Environment Institute-US Center

well as water demand and population growth,
we developed three unique Scenarios that were
analyzed as part of this study to establish a range
of plausible, future water balance conditions
throughout the ADE including:
Optimistic - lower population growth rates,
improved per capita demand, moderate
<strong>climate</strong> <strong>change</strong>
Pessimistic - more warming and extreme
<strong>climate</strong> <strong>change</strong>, high population, not as
successful per capita-use reductions
Middle of the road - ‘business as usual’
growth rates with ‘expected’ or average
<strong>climate</strong> projection
In addition, we have developed and run five
other Scenarios which tier off of the three
baseline Scenarios, making assumptions about
future adaptations to reduce water demand.
The paragraphs below include descriptions of
all the Scenarios that were created and analyzed
as part of this study, as well as summaries in
Table ‎4‐8, Page. 113.
The Scenario drivers included assumptions
about population growth (column 2), per
capita demand (column 3), and <strong>climate</strong> <strong>change</strong>
(column 4), and a set of adaptation options
(column 5). For the Optimistic Scenario (1), we
have assumed that a high population growth
rate of 8% per annum continues until 2015, with
the rate decreasing to 4% through 2025 and then
to 2% for the remainder of the study period. This
Scenario assumes that conservation programs
are successful and per capita water demand
for domestic, industrial, and garden watering
is reduced to 800 l/cap/day by 2010 and then to
700 l/c/day by 2012 according to stated policy
objects, with this demand rate continuing
through the end of the study period. Note that
this still is an extraordinary per-capita rate.
The <strong>climate</strong> <strong>change</strong> assumptions are shown
in column 3, with a 1.7ºC warming through
2050 and a 10 increase in precipitation for the
Optimistic Scenario.
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. For example, given that the
amenity, forestry, and agriculture sectors are
very water use intensive, the question of longterm
sustainability of groundwater resources
is critical. Current irrigation practices in these
sectors suggest that non-renewable groundwater
supplies could be pumped dry through the next
few decades. Much of the adaptation strategies
modeled include decreasing amenity area and
summer watering (when evaporation and
temperature are highest), decrease forestry
and agricultural area, layered on top of different
suggested population growth rates and per
capita consumption rates.
4.8.1. The Optimistic Scenarios
(1, 1.1, and 1.2)
The Optimistic Scenarios embed lower
population growth rates, more success in
reducing per capita demand, and moderate
future <strong>climate</strong> warming. The idea behind this
Optimistic Scenario was to model stated policy
objectives, optimistically assuming they will be
successfully implemented, and then layering
<strong>climate</strong> <strong>change</strong> on top of those assumptions.
Given the current rate of population growth
and aggressive development policies, one
could imagine a Scenario where population
growth rates stay very high into the middle
of the 21st century, but water conservation
programs achieve some success in reducing
per-capita demand, amenity water use is
curtailed through fallowing of planted area
and summer time irrigation is reduced as a
strategy to just maintain green-space viability
through the extreme summer heat. Reductions
in agriculture and forestry water demand are
achieved through reductions in planted area
of 30% after 2015. Scenario 1.2 makes the same
assumptions as Scenario 1.1, but without
<strong>climate</strong> <strong>change</strong> to better illustrate the relative
impact of <strong>climate</strong> on overall demand.
4.8.2. The Pessimistic Scenarios
(2, 2.1, and 2.2)
The Pessimistic Scenarios assume greater
<strong>climate</strong> warming, high population growth
rates, and marginally successful per capitause
reductions. For the Pessimistic Scenario
(2), it was assumed that population growth
continues at a rate of 8% per annum until 2015,
tapering off to 6% thereafter. This Scenario
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Climate Change Impacts, Vulnerability & Adaptation