This sector study assesses the impact of climate change from global warming and sea level rise (SLR) on the MEC's infrastructure. Infrastructure consists of the engineered systems, which provide transportation, energy, communication, water, and solid and liquid waste disposal. The aggregate value of the MEC's infrastructure assets approaches nearly $1 Trillion.
In this assessment we attempt the following:
- We review the already known risks to the infrastructure in the Metropolitan East Coast region from coastal storm surges under current climate conditions. Special attention is paid to the transportation infrastructure. Many components of the transportation systems are at elevations of only 6 to 20 feet (2 to 7m) above current sea level, exposing them to storm surges that have been modeled to reach heights in excess of 20 feet (7m) for worst-case storm tracks.
- We add to the existing storm-surge hazards the incremental hazards due to expected sea level rise (SLR). While sea level is expected to rise only by less than 3ft (1m) during the next century, it tends to increase the frequency of coastal flooding by factors of 2 to 10 by the year 2100, with a mean factor of about 3.
- We assess the consequences of the storm surges in terms of likely economic losses for the metropolitan region. We find that aggregate losses from single large storm events (not just due to coastal flooding, but including wind and other damages) may range from a few billion to more than 100 billion dollars per event. They imply losses from single large events between 0.1% and more than 10% of the region's yearly economic output. Even with sea level rise accounted for, these losses would occur sufficiently infrequent that when annualized they would amount to just tens to hundreds of millions of dollars per year. These annualized losses from coastal storms would be small enough to be absorbed readily by the 1-Trillion dollar economy of the region. However, the actual losses do not occur annualized. Rather the largest losses occur during infrequent but extreme singular events. When they occur, insurers, insured and non-insured would experience severe economic stresses. If the frequency of these and smaller events increases by factors of 2 to 10 due to the accelerating sea level rise, mitigating actions will have to be taken, the sooner the better.
- We explore innovative coping and adaptation strategies which may include modern engineering solutions, regulatory measures, taxation and/or financial or insurance discounting, and -perhaps most effectively- innovative land use, combined with buyouts and relocations
The region is already in the process to revamp its basic infrastructure at costs approaching a good fraction of a 100 Billion dollars per decade. Therefore, the most cost-effective way to harden the infrastructure against future coastal storm surge losses would be to include into the ongoing rebuilding of the infrastructure the technical standards and protective features that take note of these increased flood potentials. The best mitigation is to avoid placing new or refurbished assets at low elevations. This would require an innovative landuse plan, tough zoning enforcement, and new engineering codes that place all critical components at sufficiently high elevations, higher than currently required.
To reduce the uncertainties associated with the results from this assessment, the following data and analysis elements need to become available for future improved, more quantitative impact assessments of climate change of the region:
- A thoroughly compiled catalog of the historic storms, coastal flood heights and extents, and of associated damages and losses;
- A high-resolution model (cm to dm) of the near-shore topography (digital elevation model or DEM);
- Improved climate models that not only account for sea level rise, but also account for variations of storm frequency and intensity with changing climate;
- Accurate inventories of the major infrastructure systems and components; their exact location (in three dimensions) in GIS formats; and their associated dollar values;
- Infrastructure component and network fragilities with respect to storm surge, flooding and wind hazards;
- A GIS-based computer algorithm for computing the losses both probabilistically and for individual scenario events.