climate change on UAE - Stockholm Environment Institute-US Center

ago when sea level was a few meters higher.
When sea levels began to retreat, progradation
of mainland shore began and continues with
sedimentation and progressive infilling of
sheltered lagoons, as well as colonization of
newly emerging land as the coastline is shifting
seaward.
Sabkhas are the most obviously endangered
geological feature in the UAE. Coastal sabkhas
are regularly flooded from winter rains and
higher spring tides. Natural rainfall-pooling
patterns in the Sabkhat are already interfered
with by civil engineering projects along the
coastline. Roadway plantations and subsequent
fresh-brackish irrigation applications are
changing salinities of sabkha water and may
have negative consequences on sabkha flora and
fauna. Once easy to find near Abu Dhabi Island,
coastal sabkhas are also quickly disappearing
to make place for roads, power lines, industrial
estates and housing developments.
Even though these ecosystems have undergone
a lot <strong>change</strong>s throughout time, particularly
from infilling and fragmentation that occurs
during development, the evidence of former
coastlines can still be seen. The highway from
Abu Dhabi to the western industrial zone of
Ruwais, for example, passes across the sabkha,
and to the south, inland, the old shoreline can
be identified, a low range of hills that mark
the beginnings of the desert (Richardson and
Hellyer, n.d.). The old shoreline then reached the
low cliffs that can be seen south of the highway
to Tarif, the shore may return to that place as
seas rise, which is fine for sabkhas development
but less fine for existing road networks and
built environment that depends on coastline in
its current position.
Most sabkhas, at least coastal sabkhas, are
only a few meters above sea level. The lack
of topographic relief and altitude allows sea
water to move several kilometers inland during
high tide, rare storm surges, and even further
inland with future sea level increases. Without
adequate adaptation, sabkhas human and
faunal populations may have to relocate inland.
Additionally, any <strong>change</strong> precipitation and
sea levels due to <strong>climate</strong> <strong>change</strong> will alter the
evaporites that are at the core of ecosystem
functioning (Lieth and Menzel, 2002).
Anticipated sea level rise will lead to coastline
retreat inland, once again, and low-lying
sabkha will be flooded by the advancing waters
relatively quickly. For those coastal settlements
and existing infrastructure that are situated
in the sabkha zone, they may have a relatively
limited lifespan if and when the pace of sea level
rise increases. Even now, sabkhat are vulnerable
to exceptional meteorological events like
strong onshore winds (shamals) that can drive
seawater from lagoons inland, over the outer
parts of the sabkhas.
3.2. Mangroves
The Emirates’ mangroves have a high ecological
value to the Arabian Gulf (Saenger and Blasco,
2000; Saenger et al., 2004). Coastal vegetated
wetlands like mangroves are sensitive to <strong>climate</strong>
<strong>change</strong> and long-term sea-level <strong>change</strong> because
their location is intimately linked to sea level.
Mangroves play a vital role in the life-cycle of
many valuable seafood species and provide a
safe nesting, feeding and roosting site for many
birds (Aspinall). Mangroves also offer coastal
production by reducing wave energy The Abu
Dhabi Environment Agency’s 2006 report on
the Marine and Coastal Sectors, discusses
past efforts to inventory existing mangrove
habitat. In 2004, the Abu Dhabi’s marine atlas
project, recorded the distribution, density and
structure of mangrove vegetation throughout
Abu Dhabi Emirate; Figure ‎3‐2 is a map derived
from this survey data. Mangroves naturally
occur between Ras Ghanada in the northeast to
Marawah Island further to the west at suitable
sheltered sites that have reduced wave energy
and are protected from strong winds. Data from
remote sensing suggests that there are about 40
km 2 of mangroves in Abu Dhabi.
Sasekumar, et al., (1994) explain that mangroves
are found above sea level because the mud where
they take root needs to be totally exposed,
or free from inundation, for some period each
day. Under situations of constant inundation,
mangrove root systems are unable to take in
oxygen and new trees will be unable to take root
as seeds float in higher water. Additionally, any
increase in extreme storms may induce erosion
of the mudflats, around which mangroves thrive.
Mudflats do undergo a natural cycle of accretion
Impacts, Vulnerability & Adaptation for
Coastal Zones in the United Arab Emirates
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