Diagnosis of Impacts of Climate Change on Urban Areas




Prof. Mohamed El Raey
University of Alexandria
Regional Center for Disaster Risk Reduction
Email: melraey@gmail.com
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, 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.

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.

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.

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.

Urban Vulnerability:

From the point of view of climate change, urban areas in the Arab countries, are characterized by:

  • 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.
  • Shortage of the proactive, anticipatory planning, Strategic Environmental Assessment (SEA), site selection techniques and follow-up monitoring and law enforcement in establishing these towns.
  • Delays in reactive response due to over centralization of authorities for decision making
  • Shortage of regional and local monitoring data and geospatial data basis and regional models predicting future conditions.
  • Weak enforcement of the environmental planning and building regulations of pollution control and wastewater treatment
  • Lack of energy and water conservation programs and shortage of considerations of renewable energy resources.
  • 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
  • Shortage of information on physical and socioeconomic resilience index of the community and awareness to reduce the risk of impacts of extreme events.
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-half-degrees’ maximum limit

To adapt to potential impacts on urban towns, it is necessary to:

  • Develop institutional and human capacity through the establishment of a Regional Center for Climate Change for the Arab Countries, with national centers.
  • Adopt building codes for climate changes and enforce it by strong monitoring and periodic assessment.
  • Make sure of building of the geographic data base of all collected information on the town or city and make accessible to stakeholders
  • 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
  • Cooperate with civil society and NGO, develop a social responsibility of the community through education and training.
  • 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.
  • 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
  • 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
  • Encourage Insurance companies to promote protection for impacts of climate changes

References

  • IPCC IV, Intergovernmental Panel on Climate Change, Fourth Assessment Report, 2007
  • El Raey, M. Impact of climate change: Vulnerability and Adaptation, Coastal Areas; Arab Forum for Environment and Development, 2009
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