climate change on UAE - Stockholm Environment Institute-US Center

7 Vulnerability
assessment of
Drylands ecosystems
This section will attempt to assess the
vulnerability and impacts of drylands
ecosystems with focus on Abu Dhabi emirates.
It will present information on climatic <strong>change</strong>s,
potential impacts and adaptation measures for
the drylands ecosystems.
7.1. Observed Climatic <strong>change</strong>s in
dryland ecosystems
An assessment by the IPCC of long-term
trends in precipitation amount over many large
regions for the period 1900-2005, indicated that
drying has been observed in the Sahel, the
Mediterranean, southern Africa and parts of
southern Asia. The report has also indicated
that more intense and longer droughts have
been observed over wider areas since the 1970s,
particularly in the tropics and subtropics (IPCC,
2007). These observations are linked to higher
temperatures, decreased precipitation; <strong>change</strong>s
in sea surface temperatures, wind patterns, and
decreased snow cover.
More relevant to dryland regions is that areas
affected by drought have and will continue to
increase (IPCC, 2007). Little was reported in
the IPCC Working Group 2 report regarding
the observed impacts on crops and livestock in
drylands or other developing country regions
(Rosenzweig et al. 2007). A study had shown
that very dry land areas across the globe
(defined as areas with a PDSI of less than –3.0)
have more than doubled in extent since the
1970s, and this was associated with an initial
precipitation decrease over land related to
the El Niño-Southern Oscillation and with
subsequent increases primarily due to surface
warming (IIED, 2008).
7.2 Projected climatic <strong>change</strong>s in
dry land ecosystems
The IPCC (2007) has left no doubt that global
warming is occurring and that <strong>climate</strong> <strong>change</strong>
is human-induced, concluding that “warming of
the <strong>climate</strong> system is unequivocal” and stating
with 90 percent confidence that the net effect
of human activities on Earth since 1750 has
been warming. The report emphasized the high
uncertainties in prediction of arid ecosystem
responses to elevated CO 2 and global warming.
However, it projected a generalized warming of
over 3ºC and a 100% increase in frequency of
extremely warm years and the likely reduction
in rainfall in Southern Africa, Sahara & Central
Asia and likely increase in West Africa, East
Africa and South Asia (IPCC, 2007).
7.3. Current <strong>climate</strong> and expected
climatic <strong>change</strong> in the UAE
The <strong>climate</strong> of the UAE is characterized by high
temperatures (up to 49ºC in July), high humidity
and low rainfall. The average annual rainfall in
the mountain region (140-200 mm) and along
the east coast (100-140 mm) is generally higher
compared to the gravel plains (100-120 mm),
with the west coast receiving the lowest average
of less than 60mm (Boer, 1997).
The IPCC groups the Saudi peninsula into the
Asian division, a region expected to undergo a
wide range of climatic <strong>change</strong>s over the next
century. An assessment by the IPCC of trends in
precipitation for the period extending from 1900-
2005 indicated that drying has been observed in
the Sahel, the Mediterranean, southern Africa
and parts of southern Asia, regions with similar
<strong>climate</strong> characteristics to the peninsula. The
IPCC reported that more intense and longer
droughts have been observed over wider areas
since the 1970s, particularly in the tropics and
subtropics, but may have increased slightly in
the Arabian Peninsula (IPCC, 2007).
A recent consortium of <strong>climate</strong> scientists from
the Middle East recently compiled a database
of <strong>climate</strong> observations over the last half
century, and reported that both maximum
and minimum temperatures in the region have
shown a statistically significant increase and the
number days exceeding the 90 th percentile have
increased throughout the region (Zhang et al.,
2005). However, the report indicates that there
have been no coherent trends in precipitation
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Climate Change Impacts, Vulnerability & Adaptation