climate change on UAE - Stockholm Environment Institute-US Center

faced by water planners, including those related
to <strong>climate</strong>, watershed condition, anticipated
demand, ecosystem needs, regulatory
<strong>climate</strong>, operational objectives and available
infrastructure. The model possesses a graphical
user interface that supports the construction
of site-specific network representations of
watersheds and the water systems contained
within them, and that facilitates multiparticipant
water management dialogues
organized around scenario development
and evaluation. WEAP uses a priority-based
optimization algorithm as an alternative to
hierarchical rule-based logic that uses the
concept of Equity Groups to allocate water in
times of insufficient supply (Yates et al. 2005
a,b). More information on WEAP can be found
at http://weap21.org.
4.2. Data requirements and
acquisition
Several supporting datasets have been utilized
in this study, most notably those provided
by the Abu Dhabi Environment Agency’s
Water Resources Department in the form
of annual water resource statistical reports
that summarize regional water demands and
supplies by sector and source. Data from
these reports have been used to represent the
physical infrastructure such as desalination
plants, waste water treatment plants, and
well fields, their capacities; and how they are
connected to various demand sites. These
include estimates available groundwater
storage stratified by fresh, brackish and saline,
population and per-capita use estimates in both
the western and eastern regions of the ADE.
Climate data included daily observations of
minimum and maximum air temperature, wind
speed, relative humidity, and precipitation for
Abu Dhabi and Al Ain airport for the period
1994 through 2008.
Geographical Information System (GIS)
datasets were also use to spatially locate the
supplies and demands throughout Abu Dhabi,
and determine the amount of irrigated acreage
in each region and by type (agriculture, amenity,
forests). The GIS layers include those listed
Annex 1: Data sources and key assumptions,
and the aggregate irrigated area is summarized
in Table 4-1
4.3. Representing Water Demands
and Supplies in WEAP
Figure 4-1 shows the representation of Abu
Dhabi water supply and demand as depicted in
WEAP. The inset box shows some of the detailed
objects near and around Abu Dhabi. The
aggregate municipal and industrial demands
for the city of Abu Dhabi are represented by a
single demand node (inset; red circle). Within
this demand object are fields that represent the
number of people, their per capita demand, their
monthly use pattern, and their consumption.
Transmission losses and consumption are
depicted as % values along transmission links
and at the Abu Dhabi demand site.
The demand priority for Abu Dhabi municipal
and industrial demand is given a priority of
one - it has first priority for water supplies
that serve its needs, which are linked to the
demand node by three transmission links
(green arrows) for sources Um Al Naar, Mirfa,
and Taweelah (desalination plants designated
with green diamond model objects). Data
input for the desalination sources include their
installed capacity in millions of gallons per
day (e.g. Taweelah at 228 mgd and Un Al Naar
at 160 mgd). In 2003, the total desalinization
production was estimated at about 400 mgd,
so these two desalinization objects represent
the bulk of the potable supply. Wastewater is
conveyed from the demand node to the Mafraq
waste water treatment plant with a return flow
link (red arrow). The ‘Red-Line’ exiting the
Abu Dhabi demand node in Figure ‎4‐1 is the
conveyance to the, with the two conveyance
lines (green lines).
Transmission links from Mafraq represent
the reuse of treated waste water for nonpotable,
outdoor irrigation. Irrecoverable
transmission losses in the distribution system
from the desalinization water treatment plant
are assumed to be 15%, Consumption within
the municipal and industrial demand node
is assumed as 10% of what is delivered to the
node. The model also assumes that 80% of water
that is returned to a waste water treatment
plant can be used for outdoor irrigation (e.g.
amenity watering). These fractions are shown
along the transmission links summarizes the
drivers of municipal demands for the region
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Climate Change Impacts, Vulnerability & Adaptation