Background - Climate Change and Infrastructure, Urban Systems, and Vulnerabilities - page 8

an input-output model, they examined production and job losses and duration of recon-
struction activities, along with the benefits of upgraded defenses against flooding.
3) CLIMATE CHANGE VULNERABILITY AND IMPACT CONCERNS
FOR INFRASTRUCTURES AND URBAN SYSTEMS
Climate change issues and concerns for infrastructures and urban areas focus on climate
and weather parameters and/or events that are projected to change in magnitude or du-
ration as a result of climate change. Vulnerabilities and risks are associated with changes
in average temperature and temperature extremes, including heat and/or cold waves;
changes in amounts and paterns of precipitation, including extreme rainfall events
and flooding; changes in storm tracks, frequencies, and intensities; and sea-level rise.
In many cases, variances and extremes are more salient for infrastructures and urban
systems than are averages.
Table 1 summarizes several kinds of potential impacts from a study of climate change
vulnerabilities in Boston. Box 1 provides an example from recent experience with a
weather threat to energy infrastructure in the United States.
4) CLIMATE CHANGE ADAPTATION POTENTIALS FOR
INFRASTRUCTURE AND URBAN SYSTEMS
Infrastructures and urban systems can reduce climate change risks, increase resilience to
possible impacts, and reduce the magnitude and intensity of impacts by a range of adap-
tive behaviors: physical/capital equipment adaptations; technology and institutional ad-
aptations; self-initiated “autonomous” adaptations and “planned” adaptations related
to changes in external signals, requirements, and/or rewards; incremental adaptations
without significant changes in existing systems and/or transformational adaptations
that involve significant changes in systems or their locations.
Examples of possible adaptations to risks are depicted for Boston in Table 2 (also see
Box 3 in Section V: Relating Adaptation and Mitigation).
5) CROSS-SECTORAL INTERACTIONS AMONG
INFRASTRUCTURES
Although infrastructures and urban systems are often viewed individually - e.g., trans-
portation or water supply or wastewater/drainage - in fact they are usually highly in-
teractive and interdependent. Also drawn from the Boston case study, Table 3 illustrates
interactions among infrastructures that might be affected by climate change, and Table
4 indicates possible sectoral adaptation strategies to reduce vulnerabilities and impacts
across other sectors. More generally, the complexities of infrastructure interdependence
are illustrated by Figure 2 .
A number of experiences in the past decade have shown that such interdependencies
can lead to cascading impacts through urban infrastructures that can result in unexpect-
ed impacts in communication, water, and public health infrastructure sectors, at least in
the short term:
The Howard Street Tunnel fire in Baltimore, 2001
On July 18, 2001, a CSX freight train derailed in a through-route tunnel under Howard
Street in Baltimore. This accident started a chemical fire that continued for more than