climate change on UAE - Stockholm Environment Institute-US Center

differences in observed sea levels to the mean
as averaged from 1993 to mid-2001. The dots
are 10-day estimates (from Topex/Poseidon
Satellite in Fed and Jason Satellite) in green
and the blue solid curve corresponds to 60-day
smoothing.
Sea levels are not rising uniformly around the
world. Meehl et al. (2007) found that regional
sea-level <strong>change</strong> will depart significantly from
the global mean trends. Local (or relative)
<strong>change</strong>s in sea level differ from global trends due
to regional variations in oceanic level <strong>change</strong>
thermal expansion, geological uplift/subsidence,
sea-floor spreading, and the level of glaciation,
and relative sea level <strong>change</strong> that drives impacts
and is of concern to coastal managers (Nicholls
and Klein, 2005; Harvey, 2006a). Both sea level
rise and coastal settlement patterns have
substantial inertia, and there is high confidence
that the unavoidability of sea level rise will
continue to conflict with present and future
human development patterns (IPCC, 2007).
Coastal areas experience more SLR than the
open ocean (IPCC, 2007). According to Short
and Neckles (1999), the direct effects of sea
level rise on the coastal zones will be increased
water depths, <strong>change</strong>s in tidal variation (both
mean tide level and tidal prism), altered water
movement, and increased sea water intrusion
inland. These effects should be quite noticeable
in the shallow Arabian Gulf. In the southern
Gulf, studies have already examined sea level
rise relative to historic shorelines (Evans et al.,
1969, Taylor and Llling, 1969; Purser and Loreau,
1973; Dalongeville et al., 1993; Lambeck, 1996;
Kirkham, 1997). Others have examined sea level
in relation to geology (Uchupi et al., 1999), or
Gulf floor sedimentation (Stoffers and Ross,
1979; Sarnthein, 1972; Reynolds, 1993). About
80% of the monthly mean sea level variance can
be related to seasonal <strong>change</strong>s (Sultan et al.,
1995; IPCC, 2007).
2.1. Abrupt or rapid sea level rise
Many researchers identify abrupt or rapid sea
level rise as a major problem facing coastal
societies (Titus, 1988 and 1990; Mitchell, 1991).
Characteristics of rapid sea level rise include
both elevation in the mean level of the ocean
surface and increase in the tidal variation around
the mean (ADEA 2006). Gradual increase in
mean sea levels is much easier to adapt to than
the rapid sea level rise coastal cities may face.
Abrupt sea level rise is worrisome because it
happens on a time scale far quicker than most
societies are able to adapt.
Large, abrupt climatic <strong>change</strong>s with major
impacts are by no means new phenomena in the
course of the planet’s history. While historically,
much of these abrupt <strong>change</strong>s have been due
to natural causes, most recently, scientists
are concerned that human forcing of <strong>climate</strong>
<strong>change</strong> is affecting the probability of abrupt
<strong>change</strong> (Alley et al., 2003). Abrupt <strong>climate</strong>
<strong>change</strong> occurs when the <strong>climate</strong> system crosses
a threshold, triggering a transition to a new
state. The rate of transition is determined by
the <strong>climate</strong> system, and will likely be faster than
the cause of that transition. Rapid sea level
rise, for example, could result from crossing a
temperature threshold, after which the planet
transitions from sea level, at its current status,
to a new higher level.
Kasperson et al. (2005) conducted a thorough
review of the risk of future rapid large sealevel
rise (SLR). In their review, the potential
collapse of the West Antarctic ice sheet (WAIS)
was the primary driver of rapid SLR. Most
consider rapid sea level rise of five to ten
meters over the next several centuries to be a
worst case scenario; the timing of which is also
dependent on the rate of warming, ice sheet
melts, and reaching one of several tipping
points in the other’s <strong>climate</strong> system yielding
long-term consequences. A tipping point is a
moment in time, at which a small <strong>change</strong> yields
large, long-term consequences for the <strong>climate</strong>
system. The map in Figure ‎2‐3 suggests policyrelevant
elements with critical tipping points
in the <strong>climate</strong> system (Lenton et.al., 2008). Any
of these could plausibly be triggered in this
century, and the main conclusion was that it will
be “characterized by potentially catastrophic
consequences and high epistemic uncertainty”
(Kasperson, 2005). As such, effective risk
management demands adaptive management
regimes, vulnerability reduction, and urgent
mitigation of <strong>climate</strong> <strong>change</strong> forces, such as the
production of anthropogenic greenhouse gas
emissions.
Impacts, Vulnerability & Adaptation for
Coastal Zones in the United Arab Emirates
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