climate change on UAE - Stockholm Environment Institute-US Center

groundwater available, excluding an assumed
fresh groundwater source in the western
region of the country, near Liwa and Madinat
Zayed. This number is higher than the estimate
reported in Table 2.1, but research by GTZ
suggests a substantial freshwater lens in the
western region that is partially taken to account
here. Future analysis could, of course, modify
this assumption. Brooks et al. note that “the
GWRP calculated a total groundwater reserve
of 253 Km³ (7% fresh, 93% brackish) and the
GWAP total estimate of 640 Km³ (2.6 % fresh,
18.1 % brackish, 79.4% saline) is much larger
since groundwater of salinity of up to 100,000
mg/l TDS was included, whereas the GWRP
included groundwater with less than 15,000
mg/l TDS”. The GWRP assessment (USGS,
1996) projects that the fresh and brackish
groundwater resources will be depleted in 50
years at current groundwater abstraction rates.
Their analysis does not include the freshwater
sources in the western region. Given our initial
estimate of fresh and brackish groundwater,
these resources would be depleted in about
150 years given current extraction rate from
the agriculture and forestry sectors of about
2,500 Mm 3 /year. This variance highlights the
importance of the assumptions regarding the
current fresh and brackish groundwater supplies
in determining their long-term availability.
Figure ‎5‐5 shows the total storage of the
fresh and brackish groundwater for the three
Optimistic Scenarios. In the analysis, only the
agriculture and forestry sectors are depending
on groundwater as their supply source.
Interestingly, the relative difference between
the Optimistic Scenario with adaptation and No
Climate <strong>change</strong> (1.1) and the same Scenario that
assumes no <strong>climate</strong> <strong>change</strong> (1.2) are only slightly
different, suggesting the marginal impact that
<strong>climate</strong> <strong>change</strong> would have on groundwater
resources. The Optimistic Scenarios (1) does
not include any reductions in agriculture or
forestry demand over the study horizon and also
imposes the moderate <strong>climate</strong> <strong>change</strong> forcing.
However, as was just stated, the relative impact
of <strong>climate</strong> <strong>change</strong> on groundwater storage is
quite small, so all of the decline in groundwater
storage is attributable to the continued high
demand from the agricultural and forestry
sectors. Since the Pessimistic Scenario is really
only concerned with growth in the urban sector,
the groundwater storage results for all three
of those Scenarios are nearly identical to the
Optimistic Scenarios results just presented.
5.4. Adaptation and Mitigation to
Climate Change: Hand-in-Hand
The analysis just presented suggests the likely
range that <strong>climate</strong> <strong>change</strong> and other socioeconomic
factors will have on the water supplydemand
balance in the ADE. Given the current
state-of-the science with regards to future
<strong>climate</strong>, the analysis reports assumptions
about future per-capita demand and population
growth, and the priorities and policies associated
with agricultural production and development
will overwhelm the impacts of <strong>climate</strong> <strong>change</strong>
on the water resources sector. While this likely
the case, the analysis drives home the point
that serious consideration should be given to
the long-term goals and sustainability of the
agriculture and forestry sectors. If these sectors
continue to use water at their current rate,
they will continue to strain a limited resource.
Climate <strong>change</strong> will only hasten that position.
On the M&I side, “if freshwater supply has
to be replaced by desalinated water due to
<strong>climate</strong> <strong>change</strong>, then the cost of <strong>climate</strong> <strong>change</strong>
includes the average cost of desalination, which
is currently around US$1.00/m 3 for seawater and
US$0.60/m3 for brackish water (Zhou and Tol,
2005). The cost for freshwater chlorination is
approximately US$0.02/m 3 ” (IPCC SRES, 2008).
Water conservation will be needed to avoid the
continued expansion of desalinization capacity,
since increased dependence on desalinized
water is sub-optimal.
Increasing desalinization capacity would seem
to be a quick and easy adaptation to future
demand, but it does not come without a cost from
both a financial and environmental perspective.
Increasing, to achieve water resource reliability,
the water resources management strategy has
essentially been in investing in more energy
to produce more water. But this option must
acknowledge that desalinization and the
distribution of water accounts for a significant
share of total energy consumption, as power
plant emissions account for a significant share
of Green House Gases (GHGs). Desalinization
is not a “Green” solution. Moreover, the latest
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Climate Change Impacts, Vulnerability & Adaptation