climate change on UAE - Stockholm Environment Institute-US Center

to water using SRTM data.
In this way, the floodfill algorithm was used
to establish ‘vulnerable zones’ of inundation
at specified scenarios of sea level rise. For
detailed GIS methodological steps of how these
vulnerable zones were overlain with urban
infrastructure and coastal ecosystem data to
quantify areas and locations vulnerable to sea
level rise, see Annex 1.
4.6. Scenario development
In developing our scenarios, we modeled those
areas outside the intertidal zone to identify
areas newly inundated given certain degrees
of sea level rise. As discussed previously in the
southern Arabian Gulf the tidal range rarely
exceeds 2 meters, and the mean spring tidal
range is 1.7 and 1.9 meters. Other resources
suggest that the mean range is 1.0m while the
spring range is 1.8m. The tidal range is the
vertical difference between the highest high
tide and the lowest low tide; most extreme
tidal range (otherwise known as the spring
tide) occurs when the gravity of both the Sun
and Moon are pulling the same way or exact
opposite way (full). For simplicity and because
the SRTM data is only available in integers, we
use 2 meters as the tidal range.
SLRn = Mean Sea Level (0) + (tidal range)/2 +
n meters SLR
In practice this means that we ultimately shift
our elevation-based scenarios +1 meter to
establish sea level rise outside of the existing
tidal range:
SLRn = Mean Sea Level (0) + 1 + n meters
SLR
We have chosen to model four scenarios of sea
level rise, representing different plausible rises
over the next century or so. The likelihood of
these scenarios is largely dependent on degrees
of warming (2˚C to 4˚C) and the extent to which
global warming continues to influence ice cap
melt. We do know, however, from research by
Jim Hansen of NASA’s Goddard Institute, that
there is plausible scientific basis to show that
linear projections of sea-level rise are no longer
acceptable—making room for abrupt <strong>change</strong>s,
in the case of arctic melt, for example.
Scenario #1: No accelerated ice cap melting
i) 2050: 1 meters above mean sea level
ii) 2100: 2 meters above mean sea level
Scenario #2: Accelerated ice cap melting
iii) 2050: 3 meters above mean sea level
iv) 2100: 9 meters above mean sea level
For each scenario (where data allows), we have
quantified the area inundated for Abu Dhabi
based on the Environment Agency’s land use and
ecosystem classifications: mangrove, sabhka,
salt marsh, sea grass, built up area, empty areas,
road buffer, agriculture, forests, urban greening
or amenity, archaeology sites/areas of significant
historical/cultural value, and populations
based on a rough estimate of city location and
population. The focus of the analysis is on the
Abu Dhabi Emirate, however, the elevation data
inherently covers all UAE coastal cities, including
those summarized in Table ‎4‐3.
4.7. Results and Discussion
Cartwright et al. (2008) note that extreme
high tides tend to be experienced at certain
times of the year, most notably during the
spring and autumn full-moon spring tides. As
such the probability of sea-level rise events
causing the type of damage described in this
report is unevenly distributed throughout the
year and tends to be clustered around certain,
reasonably predictable, times of the year
(spring tides). The analysis assumes that the
government is interested in planning for at least
the shorter estimate of 2050. This is a somewhat
extended period over which fixed infrastructure
depreciates, however, given that the probability
of these extreme high tide events may increase as
the frequency and intensity of storms increases,
and that mean sea-level rise impairs the ability
of coastal systems like the sabkhas to act as
natural buffers to such events it may be worth it
to prepare coastal infrastructure for 1-3m higher
sea levels in the short term.
The impacts of sea-level rise cannot be fully
understood without some discussion of human
activities in the coastal zone. There is a growing
awareness of the potential for (often wellmeaning)
efforts aimed at responding to natural
disasters to inflict unforeseen consequences
and damage of their own that outweigh the
benefits of the action (Parry and Carter, 1998).
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Climate Change Impacts, Vulnerability & Adaptation