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Suggested Citation: "4 Assess Potential Vulnerability." National Academies of Sciences, Engineering, and Medicine. 2024. Assessing Climate Change Vulnerability at Airports: A Primer. Washington, DC: The National Academies Press. doi: 10.17226/27982.

4. Assess Potential Vulnerability

Once you understand your exposure, you can determine how those future climate conditions may affect your airport’s physical assets and operations. It is at this point that you will develop a better understanding of your airport’s vulnerabilities to climate change—which will help guide decisions about investments and adjustments to increase your resilience.

Although you should follow the approach outlined in your framework of choice, this section of the primer may be a useful starting point for considering the breadth of possible impacts. In the subsections that follow, this primer discusses categories of risk that are commonly addressed in vulnerability assessments, as well as some emerging topics that are increasingly acknowledged as important vulnerabilities.

4.1 Primary Risk Categories

The primary categories of climate risk to an airport are described below. Table 4-1 shows examples of impacts from climate hazards for each airport risk category.

Physical

An airport has many physical infrastructure assets that may be impacted by different or more intense extreme weather that results from changing climate conditions. If one or more of the infrastructure assets are no longer able to function or the service life is reduced, the airport may not be able to maintain operations. The severity of operational impact may increase if the infrastructure assets are critical. Physical assets may include infrastructure such as the terminals and runways, as well as planes and equipment.

Operational and Financial

Climate hazards may cause a disruption in the continuity of service at an airport. At airports, operational impacts center around the ability to conduct ongoing business activities based on having an onsite workforce, supplies, in service physical assets, and emergency response capacity.

Financial—or economic—impacts affect the short-term solvency of the organization and its ability to maintain or expand investments. Service disruptions, as well as costly physical damages, can threaten an airport’s financial well-being.

Airport Employees, Contractors, and Passengers

Airport employees, contractors, and passengers may experience safety hazards and changes in access due to extreme weather from a changing climate. If an airport is unprepared for safety hazards, dangerous operating conditions may occur and result in risks to airport employees, contractors, and/or passengers. Similarly, limited travel access to or from the airport via transportation networks such as roadways and rail may result in a risk due to restrictions in the level of service the airport is able to provide.

Airport Adjacent Communities

Though not commonly addressed in vulnerability assessment frameworks, airport-adjacent communities are important in assessing an airport’s risk. The business and cultural relationships between the airport and adjacent community can contribute to a local network for both the airport and community to address climate hazards together and inform the risks each may face. Identifying the vulnerability of physical connections between an airport and adjacent communities, such as transportation networks and pedestrian pathways, may inform whether an airport is at risk to restricted access to life and safety supplies due to a physical climate hazard, such as flooded or icy roadways.

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Table 4-1: Examples of Impacts from Climate Hazards by Risk Category

Climate Hazard	Impacts	Physical, Operational, and Financial	Employees, Contractors, and Passengers	Airport Adjacent Community
High temperatures	Pavement buckling and loss of non-concrete pavement integrity Increased stress on outdoor workers and some passengers (e.g., elderly) due to heat, which can trigger other acute health impacts (e.g., cardiovascular events)	Greater demand and increased costs for cooling Limits to aircraft operations due to insufficient runway lengths	Heat stress exposure of outdoor workers and some passengers (e.g., elderly) which can trigger other acute health impacts (e.g., cardiovascular events) Ambient temperature may reach flashpoint of aviation fuel at 100°F	Greater demand and increased costs for cooling causing demand pressure on local electrical grid Heat stress exposure of residents and businesses requiring increased access to local cooling shelters Vegetated (i.e., tree-shaded) areas in adjacent communities can moderate the heat island effect of airports and conversely, contribute to local heating in areas lacking vegetated areas
Heavy precipitation and flooding	Flooding and associated damage to facilities (e.g., buildings, drainage systems, navigational aids) Foundation heave*	Flight delays during severe rain events Power outages during severe storms Capital costs associated with flood mitigation and adaptation	Reduced visibility (i.e., difficulty seeing signs and other vehicles) leading to falls and crashes Slippery roads and walkways due to wet surfaces	Flooding and associated damage to facilities within airport subwatershed (e.g., buildings, drainage systems) Limited transportation network access for airport and airport adjacent community Subwatershed level flood mitigation and adaptation coordination Increase in pollutants entering downstream waterbodies due to flood waters, some of which may be from the airport
Snowstorms	Damage to navigational aids and other equipment	Limited airport access Winter operations and associated costs due to snow removal and de-icing	Cold exposure of outdoor workers Reduced visibility (i.e., difficulty seeing signs and other vehicles) leading to falls and crashes Slippery roads and walkways due to wet surfaces	Limited transportation network access for airport and airport adjacent community Greater demand and increased costs for heating causing demand pressure on local utilities Cold exposure of residents and businesses requiring increased access to local warming shelters
Ice storms	Damage to navigational aids and other equipment	Limited airport access Winter operations and associated costs due to snow removal and de-icing	Cold exposure of outdoor workers Slippery roads and walkways due to icy surfaces	Limited transportation network access for airport and airport adjacent community Greater demand and increased costs for heating causing demand pressure on local utilities Cold exposure of residents and businesses requiring increased access to local warming shelters

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Climate Hazard	Impacts	Physical, Operational, and Financial	Employees, Contractors, and Passengers	Airport Adjacent Community
Drought	Pavement or foundation damage from soil contraction, subsidence*	Reduced passenger throughput capacity* due to available potable water for use and water for emergency response Change in tourism and seasonal enplanements* Increased water demand for landscaping	Reduced water availability* for potable use and emergency response	Foundation damage from soil contraction, subsidence* affecting airport adjacent structures Reduced water availability* for potable use and emergency response
Wildfires	Destruction of assets Accumulation of smoke particulates on outdoor surfaces Equipment intake air filtration required for smoke	Reduced visibility due to smoke Access restrictions due to wildfire or smoke Increased indoor air filtration required	Reduced visibility due to smoke leading to falls and crashes Impaired air quality for outdoor workers	Destruction of buildings Reduced visibility due to smoke leading to falls and crashes Limited transportation network access for airport and airport adjacent community experiencing a wildfire
Sea level rise	Inundation of low-lying airfield buildings and other structures Flooding of runways and other airfield areas from storm drain overflows Saltwater damage (e.g., corrosion) to aircraft and equipment	Limited airport access Operational disruptions Capital costs associated with flood mitigation and adaptation Additional inspections and maintenance with associated costs	Slippery roads and walkways due to wet surfaces in affected areas Workers may be exposed to damaged electrical systems	Saltwater damage (e.g., corrosion) to buildings and local utility infrastructure Limited community access and traffic delays from high-tide flooding Subwatershed level flood mitigation and adaptation coordination
Hurricanes (including wind and storm surge)	Inundation of runways, airfield areas, access roads, and facilities Saltwater damage (e.g., corrosion) to aircraft and equipment Damage to navigational aids and other equipment Wind and water damage to buildings	Flight cancellations and delays Fuel supply and storage disruptions Limited airport access	Exposure of essential airport workers to storm conditions that reduce visibility from precipitation leading to falls and crashes Impaired water quality from overwhelmed storm water systems	Limited transportation network access for airport and airport adjacent community Disruption of power and/or water service due to damage Saltwater damage (e.g., corrosion) to buildings and local utility infrastructure

Source: Adapted from U.S. DOT Transportation Climate Change Sensitivity Matrix, unless otherwise noted.

* ACRP Report 147: Climate Change Adaptation Planning: Risk Assessment for Airports

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4.2 Emerging Risk Categories

Airports may face additional unique risks, many of which fall into emerging categories. Currently, only limited literature and guidance are available for assessing these topics. However, research on these topics is increasing and your airport may wish to consider these categories. Emerging categories to consider include:

Time Variability — Changing climate conditions at an airport may affect demand forecasts. For example, there may be changes in the number and time of year of enplanements due to variability in tourism (e.g., loss of ski tourism if ski season is shortened; reduced travel to coastal areas if extreme heat or extreme storms make the location less desirable). Expanding or shortening the tourism season for your community may result in new economic considerations and contribute to operational and financial risks.

Supply Chain — Marketplace changes in supply chain availability and reliability may disrupt operations and contribute to financial risks. For example, new and replacement heating and cooling equipment components may have longer than usual lead times resulting in reduced functionality or ability to repair affected systems.

Financial Ratings — Some financial institutions evaluate evidence of whether an airport is planning for future climate conditions to reduce liability. This may be associated with environmental, social, and governance (ESG) commitments and a consideration when assessing financial risk.

Social Dynamics — Political and social influences, such as from federal, state, and local entities addressing changing climate conditions, may contribute to risks the airport would need to assess. This may take the form of regulatory requirements informing how an airport is to evaluate and address future climate change hazards that may result in different or new burdens on the airport. The priorities of adjacent communities to address one or more climate change hazards may result in airport engagement at new frequencies and/or for different topic areas than previously experienced.

Reparations — Costs associated with restorative damages following a climate change hazard event may contribute to financial risks for an airport. For example, electric utilities have been held financially responsible for certain wildfire events. Other public agencies have utilized participatory budgeting processes to fund equitable climate solutions that redress historical harms that result in uneven climate exposure across communities, as noted in the Institute for Sustainable Communities Urban Equity Climate Compact. Although there are no known parallel cases for airports, it is important to acknowledge that the concept of reparations may be expanded to other sectors in the future. An example that airports may face is flooding of adjacent properties due to development of onsite flood solutions that result in a downstream impact.