Download Diagnosis of Impacts of Climate Change on Urban Areas

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Diagnosis of Impacts of Climate Change on Urban Areas
Prof. Mohamed El Raey
University of Alexandria
Regional Center for Disaster Risk Reduction
Email: [email protected]
Introduction
In the past few years, climate changes due to
increasing greenhouse gasses of the atmosphere
became a tangible reality. Since the industrial
revolution, Greenhouse gasses of long lifetimes
are emitted at very high rates from combustion
engines in developed and developing countries and
consequently, the global average global temperature
has already risen by about 0.8 degrees over the last
century and is accelerating. The sea level has also
been rising at accelerated rates, which menaces all
low elevation coastal cities of the world. The increase
in frequency and severity of extreme climatic events,
which has been predicted by models, has also been
well observed by increasing rates and severity of heat
waves and flash floods all over the Arab region. It is
expected that, if no action is taken to limit emissions,
the temperature rise will reach 4.5- 5 degrees, which
will cause severe damage to the environment,
economy and health conditions all over the world.
In the past few years, all countries (197 countries)
of the world, being alarmed by potential impacts
of climate changes, got together and agreed in
Paris, 2015 that the global average temperature
should not be allowed to increase over 1.5 degrees
Centigrade. Paris Agreement is still to be ratified and
implemented.
Impacts on Cities and Towns
Due to high population growth rates urban
encroachment in agricultural land and landfilling
of coastal areas have been progressing at high rates.
Also, coastal cities and coastal towns, in particular,
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are directly impacted by temperature rise, sea level
rise (SLR), and increasing frequency and severity
of extremes. High density populated cities are
vulnerable to temperature rise due to increasing
energy dissipation activities, climate changes, and
increasing frequencies and severity of heat waves.
Air pollution and increased rates of occurrence of
temperature inversions impact health directly and
indirectly. It causes deterioration of infrastructure
and its impacts on the economy are common among
all cities and towns. Impacts of extreme events include
all aspects of the quality of life including health and
socioeconomic welfare. In particular, urban areas are
more vulnerable to temperature rise due to:
Urban areas and climate
Urban areas, especially those of high-density
population, are among all other sectors vulnerable to
climate changes. In addition to deteriorating quality
of air and sea level rise impacts on coastal cities, the
temperature rise in urban is higher than in other
natural areas for the following reasons:
1. Urban areas Heat
Urban areas are highly populated agglomerations,
usually with many local industries and human
activities that involve use of energy. Energy
consumption is generally inefficient and associated
with the release of heat. The result is increased rates
of occurrence of temperature inversions, which
keeps pollution below it.
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Issue 15, September 2016
2. Heat Islands
An increase of temperature of 1-3 degrees centigrade above average, is usually observed during the daytime
over urban areas. It is termed urban heat island, and it does not usually happen over rural areas. It is associated
with multiple reflections of solar radiation and dissipation of energy in the atmosphere.
Figure 1: Heat Islands over urban areas
3. Climate changes temperature rise
The expected global increase of temperature due to excessive greenhouse gasses, mainly CO2. Carbon dioxide
has a very long lifetime in the atmosphere that exceeds 50 years, which implies that the today temperature
rise is due to emissions more than 50 years ago and will continue to increase even after complete reduction of
emissions.
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Environmental Center for Arab Towns
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4. Increase of frequency and severity of extreme events
It is shown (IPCC, IV) that with the increase in global average temperature, an increase in the frequency and
severity of extreme climatic phenomena (such as heat waves, dust storms, marine surges, flash floods and cold
waves) will occur. This has already been observed by increasing frequency and severity of heat waves and flash
floods in Cairo, Alexandria, Mecca, Dubai, Abu Dhabi, which resulted in many deaths
Vulnerable Arab cities
The most vulnerable cities of the Arab world include Alexandria, Port Said, Nowak shoot, Djibouti, Kuwait,
Dubai, Doha, and Manama. These cities are vulnerable to the impacts of SLR, however, all towns and cities
of the Arab World are vulnerable to either flash floods or heat waves or both. Table (1) shows the coastal
characteristics of vulnerable Arab countries.
Table 1: Populations and coastal characteristics of vulnerable countries of the
Arab world to potential impacts of sea level rise.
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Urban Vulnerability
From the point of view of climate change, urban
areas in the Arab countries, are characterized by:
1. Lack of institutional and human capacity for
coordinated adaptation of urban areas to climatic
changes. Shortage of proactive planning for energy
analysis and conservation, life cycle analysis of
building materials, water, and wastewater treatment
facilities.
2. Shortage of the proactive, anticipatory planning,
Strategic Environmental Assessment (SEA), site
selection techniques and follow-up monitoring and
law enforcement in establishing these towns.
3.Delays in reactive response due to over
centralization of authorities for decision making
4. Shortage of regional and local monitoring data
and geospatial data basis and regional models
predicting future conditions.
5.Weak enforcement of the environmental
planning and building regulations of pollution
control and wastewater treatment
6. Lack of energy and water conservation programs
and shortage of considerations of renewable energy
resources.
7.Inhabitants of slums and informal houses,
especially those without infrastructures are more
vulnerable to impacts of climate changes than
those who live in high class and green villas with
infrastructure
8.Shortage of information on physical and
socioeconomic resilience index of the community
and awareness to reduce the risk of impacts of
extreme events.
A Magazine for the
Environmental Center for Arab Towns
Issue 15, September 2016
Adaptation Strategies and Policy
Adaptation refers to strategies, policies, and measures
that lead to upgrade the resilience of the community
to cope up with the impacts. It should be noticed
that Mitigation and Adaptation measures are both
necessary, perhaps synergistic adaptation mitigation
measures are needed to reach the one-and-a-halfdegrees’ maximum limit.
To adapt to potential impacts on urban towns, it is
necessary to:
1.Develop institutional and human capacity
through the establishment of a Regional Center
for Climate Change for the Arab Countries, with
national centers.
2.Adopt building codes for climate changes
and enforce it by strong monitoring and periodic
assessment.
3. Make sure of building of the geographic data
base of all collected information on the town or city
and make accessible to stakeholders
4. Initiate a Risk Reduction Plan for climate change
extremes. Establish a Reactive and Proactive Planning
and Follow Up unit in each town. Specifically, to
carry out:
a. a risk assessment study
b. a risk reduction study
c. a contingency plan
d. make sure stakeholders participation
5. Cooperate with civil society and NGO, develop
a social responsibility of the community through
education and training.
6. Make separate collection of wastewater and
stormwater and collect storm water. Upgrade
wastewater treatment and utilize in irrigation of
trees. Carry out research on drought tolerant plants
and cultivate along roads.
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7. Promote renewable energy resources. Specifically:
a. Carry out water and energy conservation programs
b. Introduce energy and water conservation programs in the educational system.
c. Develop green technology, green economics and energy saving green buildings and promote it by examples of governmental buildings
8. Upgrade coastal community resilience to extreme events by adopting ICZM concepts involving community
participation
a. identifying and studying coastal hazards,
b. upgrading awareness of the community
c. Building breakwaters and coastal defenses and raising level of ditches, identify stream torrents and make sure to keep it clear for flash floods
d. encourage adaptation measures and entrepreneurship projects among students
9. Encourage Insurance companies to promote protection for impacts of climate changes
References
1.
IPCC IV, Intergovernmental Panel on Climate Change, Fourth Assessment Report, 2007
2.
El Raey, M. Impact of climate change: Vulnerability and Adaptation, Coastal Areas; Arab Forum for Environment and Development, 2009
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