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Urban Environments and COP3

What is the Greenhouse Effect?

In the long term, the earth must shed energy into space at the same rate at which it absorbs energy from the sun. Solar energy arrives in the form of short-wavelength radiation. Most of it passes straight through the atmosphere to warm the earth's surface. The earth gets rid of this energy in the form of long-wavelength, infra-red radiation.

Most of the infra-red radiation emitted upwards by the earth's surface is absorbed in the atmosphere by water vapour, carbon dioxide, and other naturally occurring "greenhouse gases". These gases prevent energy from passing directly from the surface out into space. A slower more indirect process transport the energy high into the atmosphere and radiate it into space.

By increasing the atmosphere's ability to absorb infra-red energy, our greehouse gas emissions are disturbing the way Climate maintains this balance between incoming and outgoing energy. A doubling of the concentration of long-lived greenhouse gases would, if nothing else is changed, reduce the rate at which the planet can shed energy into space by about 2 percent. The climate somehow will have to adjust to get rid of the extra energy: over the entire earth, the 2 percent amounts to trapping the energy content of some three million tons of oil every minute.
"Understanding Climate Change: A Beginners Guide to the UN Framework Convention" Geneva: Information Unit on Climate change.

The Third Conference of Parties of the UN Framework Convention on Climate Change (UNFCCC). At COP3, which was held in Kyoto in December 1997, countries negotiated emission targets in greenhouse gases (GHGs). The conference followed two others, COP1 in Berlin - March 1995, and COP2 in Geneva - July, 1996.

While European countries have driven for a fallback to a 15 percent reduction of 1991 CO2 levels by the year 2010, USA and Japan have been reluctant to show leadership in the issue, opting instead for a less than 5 percent reduction.

The link between COP3 and Urban Environments is a two way street. Urban areas effect and are affected by climate change (and its primary villain, CO2) both directly and indirectly. The mega concentration of men and machines in cities are a major contributor to CO2 emissions. For example, more than 400 vehicles are added to the already congested streets of Bangkok everyday. Urban activities (vehicles, industrial activities, garbage incineration etc.) generate a considerable amount of CO2. Higher CO2 levels undoubtedly affect urban dwellers, in terms of respiratory illness, higher temperatures, and a host of related maladies.

But 'climate change' is more than just CO2 levels. It is more than global warming, more than ozone depletion. Climate change is more than the sum of its parts. Rain patterns may change, climate and agricultural zones may shift towards the poles, melting glaciers and thermal expansion of sea water may raise sea levels, threatening low-lying coastal areas and small islands - the cause-and-effect patterns are endless.

Combating the effects of climate change, from an urban perspective, requires a concerted framework within which disparate actions can be positioned and brought together - so that collective effects and efforts can be realized. A cooperative rather than a conforntational approach needs to be adopted, where local actions at the grassroots level add up, collectively, to a more balanced environmental existence.

Infrastructure, industry, and human settlements

  • Climate change will have some negative effects on humanity's physical assets. Some of the most valuable infrastructure includes industrial plants and products; equipment for producing and distributing energy; roads, ports, and other transportation facilities; residential and commercial properties; and coastal embankments. While climate change may have important consequences for infrastructure, they are likely to be smaller than those resulting from demographic, technological, and market changes, in good part because of the many opportunities for adaptation.

  • Industrial, energy, and transport infrastructure may be damaged. Changes in temperature, precipitation, or extreme events can destroy exposed infra- structure or affect productive output. Among the extreme events that may become more frequent or intense in some regions are coastal storm surges, floods, and landslides induced by local downpours, windstorms, rapid snow-melt, tropical cyclones and hurricanes, and drought-induced forest and bush fires.

  • Some economic activities are particularly vulnerable. In general, the climate sensitivity of the industry, energy, and transportation sectors is relatively low compared to that of agriculture and natural ecosystems. Most susceptible to surprises, sudden changes, and extreme events are agro-industry; the production of hydroelectricity, biomass, and other forms of renewable energy; energy use; construction; some transportation activities; and infrastructure located in coastal zones, on permafrost, or other vulnerable areas.

  • Rising sea levels could have the most dramatic and direct consequences. Many coastlines are highly developed and contain human settlements, industry, ports, and other infrastructure. Among the most vulnerable are some small island nations, developing countries, and densely populated coasts that currently lack extensive sea and coastal defense systems. Sea-level rise, storm surges, and flooding cauld force populations to migrate, with additional consequences for infrastructure further in-land.

  • The property insurance sector is particularly vulnerable to extreme climate events. A greater risk of extreme events due to climate change could lead to higher insurance premiums or the withdrawal of insurance coverage in some vulnerable areas. Changes in climate variability and the risk of extreme events may be hard to detect or predict, making it difficult for insurance companies to adjust their premiums correctly. If such problems lead these fir ms to insolvency, they may not be able to honor outstanding insurance contracts. This in turn could weaken other economic sectors, such as banking.

  • Industry would experience many indirect effects... Because economic activities are so inter connected, an impact on one sector can affect the entire economy. Industry, energy, and transportation are likely to feel knack-on effects via climate-sensitive resource sectors such as agro- industry and biomass production. Climate-sensitive markets will also send signals, such as a changing energy demand for heating or cooling buildings. The result will be an aggregation of many individual impacts.

  • would human settlements. For example, a decline in the productivity of natural re- sources in rural areas may accelerate rural-to-urban migration, especially in the developing world. Migration in response to chronic crop failures, regional flooding, or drought would put pressure on existing housing, water, food, and health systems.

  • Settlements stressed by population growth, poverty, industrializatinn, and environmental degradation are the most vulnerable. Also at risk are large primary coastal cities, squatter camps located in flood plains and on steep hillsides, settlements in forested areas vulnerable to increased seasonal wildfires, and communities that depend on subsistence agriculture or on commercial fishing. In all cases, the poorest people will be the most affected.

  • Human infrastructure can be protected through well-chosen policies end management strategies. The life cycles for planning and investing in infrastructure are often short enough to allow managers to anticipate future climate change. They could adapt to climate change by replacing capital at the normal pace with more appropriate designs and locations. However, it cannot be assumed that people and organizations will always adopt such adaptation strategies automatically. Governments may need to set policy and regulatory frameworks to encourage private action. They may also need to. take direct action to protect certain vulnerable infrastructure. The message, then, is clear: future risks can be reduced if climate change is incorporated into all current planning.

  • Diversifying the economy can offer additional protection. Developing countries that rely on a limited number of crops or other resources are economically vulnerable to climate change. When combined with improved management practices such as "integrated coastal management", economic diversification can be an important precautionary response. However, these strategies will often encounter resistance. Some of the possible constraints are technological advancement, human resources, finances, cultural and social sensitivities, and political and legal obstacles. The lack of financial and human resources is especially acute for developing countries.

Source (for this box): Climate Change Information Sheet 15. IUC, UNEP, 1997.

Hari Srinivas
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