climate change on UAE - Stockholm Environment Institute-US Center

Table ‎3‐2. Shwaib diversion structure.
Project Item Dimensions Capacity Mm3
Shwaib Dam Length 3000 m, height 11m 5
Approach Channel Length 3600 m, width 150 m 5.5
Shwaib Reservoirs Seven reservoirs 21
Total Shwaib Dam and Reservoirs project 31.5
activity and its availability by aquifer type
and surrounding development (ADEA, 2002).
Currently, the highest risks of flash flooding
occur in wadis Shik, Sidr and Ain Al Faydah
and the lowest risk in wadis Khuqayrah and
Muraykhat. The predicted long term annual
average runoff for the former basins is 1.96 Mm³/
yr and for the latter, 13.78 Mm³/yr.
Droughts, floods, and other events that alter
rainfall may overwhelm even an advanced
society’s ability to cope. Archeological evidence
suggests that the abandonment of several
cities in the course of history can be linked to
water scarcity and <strong>change</strong>s in water availability.
Flash flooding and any subsequent inability to
capture rainfall adequately will lead to extreme
runoff, nutrient loading, and, depending on
proximity to coastlines, sedimentation of
coastal ecosystems like sensitive corals.
Abu Dhabi has invested in new dams across
the Emirate. Designed to divert wadi flow into
surface reservoirs, as temperatures rise surface
water reserves are increasingly at risk. Warmer
air, while increasing evaporation of surface
water, also means that the atmosphere holds
more moisture and rainfall patterns will shift.
Increasing frequency of extreme and/or erratic
rainfall events have led to dam overflow and
flash flooding in other countries, and while
it is unlikely that these kinds of events will
occur in the UAE, the possibility still exists,
putting downstream agriculture at risk of
flash floods (Postel, 1999). Water quantities
that pass through the Shabit structure are
summarized in Table 3-3; the main beneficiary
of the structure’s enhancement of groundwater
recharge is agriculture as numerous farms exist
immediately south of the diversion structure.
3.7. "Greening the desert": a vision
at risk
UAE President Sheikh Zayed bin Sultan Al
Nahyan dreamed of turning the country green.
Over the last few decades, a massive programme
of afforestation has led to the planting of over
120 million trees, as well as 25 million date
palms. Some of these trees were planted in
urban centres, where carefully-maintained
parks and luxuriant roadside gardens offer
a pleasing quality of life for the people. Most
of the planting, though, has been conducted
in the desert, where huge new forests have
been established. This “greening the desert”
initiative has an important cultural value for
Abu Dhabi, and serious consideration will are
needed in determining the costs and benefits
of continuing to green the desert, given the
challenges of <strong>climate</strong> <strong>change</strong>.
Climate <strong>change</strong> has a profound impact on the
forestry sector. This includes changing the
habitat location of forest species, especially
the less tolerant ones and the extinction of low
tolerant species. The Municipality Agriculture
Department explains that irrigation of forestry
is undertaken mostly, with a small number of
farms, parks, gardens and road verge projects.
Based on an 8-hour/day pumping regime, the
combined water requirement is about 64Mm³/d.
The Ministry also notes that trees tend to be
under-irrigated and species are chosen that are
tolerant of the salinity levels of groundwater.
3.8. Vulnerability of irrigated
agriculture
Ancient civilizations depended on irrigation to
sustain agriculture just as much of the world does
now. At least half a dozen major irrigation-based
civilizations have been undermined by salt, silt,
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Climate Change Impacts, Vulnerability & Adaptation