climate change on UAE - Stockholm Environment Institute-US Center

Temperature Change (degrees C)
by 2050.
Rainfall Change (%)
Figure 3-6. Maximum and minimum projected
temperature and rainfall <strong>change</strong>. (UAE, 2006)
GCM outputs illustrated in Figure 3-6 show that
temperatures are projected to be between about
1.6ºC and 2.9ºC warmer in 2050 than they were
over the period 1961-90, and between 2.3ºC and
5.9ºC warmer than this baseline period by 2100.
The precipitation projections, however, are more
varied. Some models project a dryer region with
decreasing precipitation, while others project
a wetter region with a significant increase in
precipitation. Figure ‎3‐8 in Section 3.5 conveys
the projection of rainfall in 2050 to be between
20% less to 10% more than has occurred over
the period 1961-90, and between 45% less to 22%
more by 2100. Additionally, the IPCC notes an
increasing trend in the extreme events observed
during the last 50 years, particularly heavy
precipitation events, hot days, hot nights and
heat waves. Projections indicate this trend will
continue, if not worsen.
3.4. Temperature Increase and
diminished surface water
Reserves
Projected <strong>change</strong>s in monthly temperature
vary widely across the various GCMs, Scenarios
considered, and cities within the UAE. Average
monthly temperatures in 2050 will be warmer
than they were for the corresponding months
over the period 1961-90:- from 1.6ºC in January
to about 2.5ºC in September (Figure ‎3‐8).
Similarly, for 2100, increases in average monthly
temperature could range from about 3.3ºC in
February to about 4.5ºC in October (again,
relative to the corresponding monthly average
over the 1961-90 baseline periods).
Temperature strongly influences the amount
of evaporation in an area. In hot, dry <strong>climate</strong>
evaporation of irrigation water is a serious
problem whether from the soil, plant leaves
or other wet surfaces. Improving irrigation
efficiency allows farmers to avoid severe water
loss. The key is custom-designed strategies to get
more output and benefit from water by creating
a best-fit technology linked to local <strong>climate</strong>,
hydrology, water use patterns, environmental
conditions, and other relevant characteristics.
3.5. Increased monthly
precipitation variability
Rainfall within Abu Dhabi Emirate is erratic
both in time and space. Rainfall provides water
for runoff, which eventually results in aquifer
recharge, especially in the eastern regions where
numerous wadi systems cross over the border
from Oman to provide preferential pathways for
percolation and recharge. This recharge water
is important, however, it only contributes, on
average, 4 % annually to the Emirate’s total water
consumption. Even so, <strong>change</strong>s in precipitation
patterns threaten to eliminate even that small
contribution to Emirate water supply.
Precipitation projections show even greater
variation than temperature. Some models
project a dryer region with decreasing
precipitation, while others project a wetter
region with a significant increase in precipitation.
As illustrated in Figure ‎3‐8, average monthly
rainfall in 2050 is projected to range between
8% less in April to about 45% more than these
corresponding months over the period 1961-90.
For 2100, average monthly rainfall <strong>change</strong>s are
projected to range between 15% less in June to
about 88% more in September, relative to the
1961-90 baseline period.
Mean annual rainfall for the western region of
the Emirate is less than 50 mm/yr and for the
eastern region, varies between 80-100 mm/yr.
An estimate of 100 mm/yr has been shown to be
required in order to activate sufficient runoff to
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Climate Change Impacts, Vulnerability & Adaptation