Introduction
Climate change refers to long-term variations in local or global weather patterns caused by natural or human activities. These changes, lasting decades or more, affect various locations and are influenced by factors such as rainfall, temperature, sea level, and extreme weather events. Human activities like excessive use of fossil fuels, deforestation, and industrialization are the leading causes of climate change, resulting in increased greenhouse gases that trap heat in the atmosphere. This leads to rising sea levels, frequent and severe weather events, and changes in ecosystems and wildlife habitats. Climate change is accelerating and affecting significant parts of the world, with some areas being more affected than others. Vulnerable groups, such as indigenous disadvantaged peoples and low-income communities, are disproportionately affected.
According to Kidnie et al.(2015), climate change describes long-term changes to the earth's climate, such as shifts in temperature, precipitation and weather patterns. Human activities are one of the leading causes of this alternation. The use of fossil fuels and deforestation are a few examples that send greenhouse gases into the earth's atmosphere, trapping heat. Rising sea levels, more frequent and intense heat waves, droughts, floods, storms, and modifications to ecosystems and species are only a few of the effects of climate change on natural and human systems. The impact of climate change frequently falls disproportionately on vulnerable groups, such as indigenous disadvantaged peoples and low-income communities.
According to Theuns Henning (2017), climate change is the observed variations in annual average temperatures, rainfall and other climate indicators. There is substantial evidence that climate change is accelerating and that significant portions of the world are affected by these changes in our environment. Some locations will be more impacted than others by climate change, notwithstanding disagreement over its sources. Many nations anticipated to be most affected by climate change are also the least prepared to deal with it.
According to Glen Brown et al. (2018), due to natural or human causes, long-term variations in local or global weather patterns are considered climate change. The changes last for an extended time, typically decades or more. The average global temperature has increased by 1.1°C since the beginning of the industrial era, and it is predicted to keep rising unless considerable steps are taken to cut greenhouse gas emissions. Extreme weather phenomena like heatwaves, droughts, floods, and storms are occurring more frequently and with greater ferocity. For instance, since the 1950s, there has been a tenfold rise in the frequency of intense heat waves. The melting of glaciers and ice sheets, along with the warming of seawater and its expansion, are the leading causes of increasing sea levels. Since the beginning of the Industrial Revolution, sea levels have increased by roughly 20 cm; by the end of the century, they are expected to have increased by another 30-110 cm. The specifics of changes depend on the location of consideration. For example, in British Columbia, changes in rainfall patterns, temperature, sea level and frequency & severity of extreme occurrences are examples of ongoing climate change. The new trend now is hotter & drier summers, warmer winters with more rainfall, more intense and frequent storms, extreme wind and rising sea levels are a few specific examples. As a result, climate change has created a new circumstance for more frequent flooding, droughts, forest fires and several other difficulties.
According to de Abreu et al. (2022), weather patterns and average temperatures are changing over the long term due to climate change. Human interventions such as fossil fuels, deforestation and industrialization are the leading causes of human-induced climate change. These human action result in increased greenhouse gases that traps heat in the earth's atmosphere, causing increased earth's temperature. Rising sea levels, frequent & severe weather events, and changes in ecosystems and wildlife habitat are a few of the examples of the effects.
Bhamidipati (2015) indicates that we still have a poor grasp of the impacts of climate change on human lives and our infrastructure. The prediction of occurrence, size, location and duration is difficult. There are mitigation and adaptation measures to deal with climate change; however, the long-term strategies to deal with climate change are not yet effective.
What are the effects and impacts of climate change on road infrastructure?
Glen Brown et al. (2018) argue in their climate change and asset management framework that the impact of climate change on roads and other infrastructure has added more challenges in providing the appropriate levels of service. It increases the cost of managing hazards by amplifying them. Natural resources will be impacted by climate change as well. These resources are vital to the delivery of services to all communities. The effects of climate change could harm wetlands, creeks, deltas, foreshore regions, forests, groundwater aquifers, and other natural resources. Soil instability, ground movement, and slope instability may result in road damage from landslides, erosion, and embankment failure. Thermal cracking, rutting, frost heave, and thaw weakening occur more frequently and with greater severity. More frequently surpassed culvert and storm sewer capacity, resulting in road washouts. Low-lying roads, causeways, and bridges are in significant danger of flooding or damage.
The framework explains the infrastructure-related cascading effects of climate change. Because infrastructure systems are interconnected and dependent on one another, changes to one system may have an effect on how well another system functions. Multiple infrastructure-owning agencies may be affected by cascading consequences, which makes emergency planning and response more difficult. Examples of cascading failures include reservoir dam failures that result in the loss of a community's source of drinking water and harm to the infrastructure and upstream land. Communities may suffer substantial repercussions from cascading effects, such as disruptions to vital services, financial losses, and public health threats. Local governments may enhance the resilience of infrastructure systems, guarantee the long-term sustainability of service delivery, and better plan for and respond to catastrophes by considering the possible cascading impacts of climate change on infrastructure (Glen Brown et al.,2018)
According to de Abreu et al. (2022), increased road damage may result from more frequent and severe weather events, including heavy rain, flooding, and excessive heat due to climate change. For example, increased rainfall intensity may result in landslides and erosion, closing roads and harming bridges and culverts. In contrast, changes in rainfall patterns can lead to droughts, causing soil shrinkage and cracking, leading to pavement damage. On the other hand, pavement can expand and crack under extreme heat, increasing maintenance costs and lowering road safety. Coastal erosion and floods brought on by rising sea levels can harm roads and bridges and interfere with transportation activities. Similarly, flooding can accelerate the corrosion of infrastructure assets, especially for bridges and other specialized structures. Road erosion can weaken drainage systems, causing flooding and infrastructural damage. Increased maintenance costs, decreased road safety, and disruptions in transportation operations are all potential consequences of climate change's effects on road infrastructure.
Theuns Henning (2017), in their research, argues that extreme rainfall causes increased seepage and infiltration into the pavement, base course and subgrade, increased hydrodynamic pressure, decreased cohesion of soil compaction, and can thoroughly wash out the road structures and pavements. Soil moisture can be altered entirely due to seasonal and annual average rainfall, affecting the structural integrity of pavements and water-crossing structures. Change in precipitation increases the risk of increased flood events due to runoffs and further triggers landslides, slope failure and damage to the road structures. A growing trend for maximum temperature and frequent heat waves can affect pavement integrity, result in rutting, cracking, and deformation, and reduce resistance against skids. On the other hand, the increasing trend of frequency and intensity of extreme weather conditions leads towards the need for additional resources for road maintenance and a reduction in the useful life of road assets. It affects the smooth operation of transportation services.
The study further distinguishes between two types of climate change impacts: slow-changing trends and shock events. The gradual alternation in climate patterns over a long period is known as a slow-changing trend. For example, gradual change in average temperature, rainfall and sea level rise. Road agencies shall take consideration of these trends for the long-term road asset management policies and strategies as they may impact road infrastructure for the long term. Shock events, however, are sudden and extreme weather events that can seriously harm the road's assets. For example, storms, mass movement, floods and intense heatwaves. Road managers must have procedures to respond to shock events and reduce damage to prevent immediate and severe effects on road infrastructure. Shock events require a different approach to network operations and management than slow-moving trends (Theuns Henning, 2017).
In their work, Kidnie et al. (2015) outline numerous effects of climate change on road infrastructure, including more frequent and severe flooding incidents, increased frequency mass movement, heat-related damage to roads, reduced snow and ice coverage in some areas, and disruptions to journey time reliability. These effects can raise damage risk and interruption to transportation networks, making planning, building, operating, and maintaining road infrastructure more difficult and expensive.
Meyer et al. (2010) present the future concern, indicating that precipitation will be more intense, which increases the risk of flooding, especially during the summer. Increased flooding and rainfall can harm bridges and highways and raise the danger of flooding in the early spring as snowpacks melt. On the other hand, sea level rise can engulf low-lying transportation hubs, including ports and highways along the coast. Rising temperatures are the cause of the rapid deterioration of pavement. Modifications to the ecological functions of the land adjacent to roadways may have an impact on current wetland and habitat banks and environmental mitigation techniques. These modifications may increase the vulnerability of the transportation infrastructure to damage and necessitate more regular upkeep and repairs.
Meyer et al. (2015) have provided the impacts of climate change on the operations and maintenance of road assets. The intense heat is hampering road-building efforts due to safety concerns for highway workers. On the other hand, thermal expansion of bridge joints can negatively impact how well a bridge functions and raise maintenance costs because of severe temperatures. Because of the runoff, there is a higher risk of landslides, slope failures, and floods, which results in road washouts and closures and the need for road maintenance and reconstruction. In colder regions, avalanches can influence highway maintenance and operations caused by wet snow, rain, or snow events. Similarly, flooding and damage to coastal roads brought on by storm surges and sea level rise may impact how well the highways function. The increased frequency and severity of flooding that underground tunnels and other low-lying infrastructure would encounter due to sea level rise and storm surges might impact highway maintenance and operation. More transportation disruptions are also expected as a result of higher cyclone intensity. Meyer et al. (2015) provide a detailed list of impacts, see table 1.
Why is it necessary to integrate climate change aspects into Road asset management?
As stated in the previous chapter, the infrastructure systems and service delivery are at risk due to climate change, resulting in decreased functionality and useful life. Specifically, there is increased strain on infrastructure systems and stress on natural resources. Transport management authorities, including local governments, can recognize and deal with these concerns by including climate change in their asset management strategy, allowing increased infrastructure systems' resilience and guaranteeing the long-term viability of service provision. The effects of climate change could raise the legal risk that local governments are exposed to by establishing distinct, documented, approved, and published levels of service that can give local governments a policy defence; asset management aids in the control of liability concerns. The asset management approach helps assess trade-offs between the cost of providing a desired level of service and all types of risk, including risks due to climate change. Adapting climate change mitigation measures in asset management helps manage climate risks more effectively. It further helps achieve balanced investments in infrastructure, providing sustainable services. In summary, integrating climate change into asset management allows local governments to identify and mitigate climate change risks, increase the resilience of infrastructure systems, and guarantee the long-term sustainability of service delivery (Glen Brown, 2018).
de Abreu et al. (2022) argues that transportation systems and infrastructure are developed to endure typical weather patterns based on historical data; however, climate change, on the other hand, brings more extreme weather occurrence that falls outside of the "typical" range. For example, increased rainfall amounts, varied precipitation patterns, and more extreme weather events are only a few effects of climate change that may affect the road transportation system's infrastructure and are generally not considered during the planning, design, and implementation of such infrastructure.
Theuns Henning (2017) outlines the reasons why climate change aspects need to be considered. As per their work, the frequency and severity of extreme weather events are predicted to grow due to climate change, which could substantially affect the infrastructure of roads. Road networks are essential to transportation infrastructure, and their disruption can have economic and social impacts. By taking climate change into account while managing road assets, it is possible to increase the resilience of the road network and lower the risk of damage and interruption. Measures to adapt to climate change can also reduce lifecycle costs such as operations and maintenance costs and increase the useful life of road assets. Furthermore, road asset management that considers climate change can also help ensure that road networks can promote sustainable development and lower greenhouse gas emissions.
According to Kidnie et al. (2015), it is necessary to integrate climate change aspects into road infrastructure planning and decision-making for several reasons. Firstly, Climate change is causing a significant impact on road infrastructure, with future consequences likely to increase. Historical data is insufficient to predict the future effects, necessitating adaptation strategies to protect long-term investments and ensure the resilience of transportation systems. Secondly, road authorities should incorporate vulnerability assessment results into asset management plans, inventories, and policies to manage risks and ensure transportation systems are resilient to potential hazards. Thirdly, integrating climate change into road infrastructure planning can reduce greenhouse gas emissions by designing sustainable, energy-efficient transportation systems, promoting a more sustainable future. Lastly, the climate change adaptation framework for road infrastructure aids authorities in prioritizing measures, allocating resources, ensuring transportation systems' resilience to hazards, protecting long-term investments, and maintaining effective functioning in a changing climate.
Meyer et al. (2010) indicate the need for an adaptive management approach. He argues that the systems for managing transportation assets must employ an adaptive management strategy. It helps transportation agencies systematically consider climate change's consequences when managing and preserving infrastructure assets. By this, administrators arrive at the most economical strategy for system adaptation to changing environmental conditions. The strategy entails keeping an eye on evolving conditions, adapting as necessary, and responding accordingly. This strategy can make transportation organizations more climate change-resistant. Additionally, it can assist organizations in making informed investment decisions that consider the risk associated with climate-related changes.
Meyer et al. (2015), in their other report, indicate the need to understand the hazards connected with a changing climate that has been brought to light by severe natural catastrophes, including Hurricanes Katrina and Irene, Superstorm Sandy, massive flooding in the Midwest, and large forest fires in the west in the United States. Understanding the dangers of a changing climate will help transportation organizations better prepare for and respond to extreme weather events. There are concerns about how asset management systems and performance-based decision-making in state departments of transportation (DOTs) could be connected to the hazards associated with climate change and extreme weather occurrences. Transportation authorities can better comprehend the hazards associated with a changing environment and establish plans to manage those risks by incorporating climate change and extreme weather factors into Transportation Asset Management Plans.
The transport infrastructure, such as roads, is threatened by the effects of climate change, and there is a need for adaptation measures that include actions such as protecting, maintaining, renewing, and building climate-resilient infrastructure. The asset management approach is vital for climate change adaptation, especially for long-term asset management decision-making to make the transport infrastructure more resilient (Bhamidipati, 2015).
How climate change and disaster resilience can be integrated with RAM?
Glen Brown (2018) proposed three strategies for managing climate change: mitigation, adaptation, and recovery. Mitigation focuses on reducing greenhouse gas emissions, such as transitioning to renewable energy sources. Adaptation increases resilience, such as building sea walls and developing early warning systems. Recovery involves responding to climate change impacts, such as repairing infrastructure and relocating communities. Combining these strategies ensures the long-term sustainability of service delivery.
The same framework further describes steps integrating climate change into infrastructure management. The basis for the stages of integration is establishing an asset inventory (the asset type, age, location, remaining useful life, etc.) that helps assess assets in terms of climate vulnerabilities. On the other hand, a clear understanding of possible climate change impact in the country/region of consideration is another important basis. It includes historical data on temperature, rainfall, and sea level rise and can be collected through portals such as Plan2Adapt. The framework then describes the assess-plan-implementation cycle (figure 1) as a basis for the CC integration. Under the assessment step, the authority shall assess AM practices, including analyzing the extent of current integration and the gaps. It also includes vulnerability assessments of the infrastructure assets. Under the planning step, it recommends formulating infrastructure asset management policies and strategies that ensure agencies' commitment towards integration and detailed agency approach to CC adaptation, mitigation, and asset management. It also includes long-term AM plans that are complemented with financial plans. Under the implementation step, the framework highlights AM implementation practice with integrated CC response. It also provides monitoring, evaluation and reporting of the achieved resilience (Glen Brown, 2018).
Fig 1- Framework for CC integration in asset management (Glen Brown, 2018)
De Abreu et al.(2022) outlined two types of adaptation measures in their review article. The first is the hard adaptation, also known as structural measures, which includes protecting road corridors with engineered structures, redesigning or relocating road facilities, Increasing pavement thickness and strength, using permeable pavement to manage intense precipitation, implementing pavement irrigation to manage high temperatures, using vegetation to stabilize slopes and reduce erosion and building sea walls and other coastal protection structures to prevent erosion and flooding. Hard adaptation includes building infrastructure better through design improvements. On the other hand, soft adaptation measures are non-structural measures and include incorporating climate change considerations into transportation planning, developing dynamic adaptation approaches, promoting sustainable practices, encouraging low-carbon modes, and implementing land use policies to reduce private vehicle reliance.
World Bank Group published a technical report in 2017 outlining the approach for integrating CC in road asset management. Theuns Henning (2017) describes four key strategies for addressing climate change impacts on road infrastructure: sectoral and spatial planning, resilient infrastructure solutions, enabling environment, and post-disaster risk and recovery support. It emphasizes vulnerability assessments, long-term plans, investing in physical infrastructure, building/rebuilding resilient road infrastructure, raising awareness, developing policies, and incorporating climate change considerations into the repair and rebuild process to ensure resilience to future climate risks. These four pillars provide a comprehensive framework for integrating climate change considerations into road asset management. By addressing each of these pillars, road managers can develop strategies and plans that reduce the vulnerability of road infrastructure to climate change impacts and ensure the long-term resilience of road networks. The report further provides an adaptation strategy concerning seven asset management components. An adaptation strategy is presented by Meyer et al. (2010). See below table 2.
Table 2 - Adaptation Strategy (Meyer et al., 2010)
Kidnie et al. (2015), in their international CC adaptation framework for road infrastructure, provide four stages of adaptation framework. The first stage includes Identifying scope, variables, risks, and data. In this stage, the agencies need to establish the objectives and scope of the assessment, define critical tasks and plan of delivery, stakeholder engagement, and finally assess climate vulnerability, adaptive capacity, and project scenarios. The second stage is about assessing risks and prioritizing. It includes an assessment of the probability of the climate change impacts, their severity and risk rating. The third stage consists of developing and selecting adaptation strategies, including an adaptation action plan. The last stage includes using the previous stages' findings and the learnings for decision-making. It further comprises providing continued awareness and capacity enhancement training, effective communication, development of the business plan and monitoring the progress against desired outputs and outcomes. The systematic assessment of climate risks and opportunities, development of adaptation responses, and integration of findings into decision-making processes enable road authorities to manage risks and ensure transportation system resilience.
Meyer et al. (2010) provide adaptation strategies concerning impact categories based on their literature review. Sea level rise is one of the impact categories. To deal with sea level rise, coastal protection measures must be developed. Seawalls, levees, and flood barriers are a few examples.On the other hand, critical infrastructure such as roads and bridges must be elevated to avoid the impact of rising sea levels. Another preventive measure is to relocate infrastructure in safer areas far from those vulnerable to sea level rise. Increased temperatures are another impact category. Retrofitting is a practical strategy for existing road infrastructure, making it more resilient. Developing design guidelines for new infrastructure considering the anticipated effects of increased temperatures can be another adaptation measure. More intense precipitation is another aspect of climate change's impact. To deal with it, the road systems must be designed with a better drainage system to handle increased flow. Retrofitting existing road assets is another measure. Design guidelines now need to incorporate the anticipated effects of intense rainfall.
Meyer et al. (2015) wrote a report for AASHTO that aims to integrate climate change and extreme weather considerations into Transportation Asset Management Plans (TAMPS) for DOTs. It involves identifying potential impacts, developing a risk assessment framework, performance measures, adaptation strategies, and decision-making tools, and integrating these into existing asset management systems. The proposal also suggests using climate models and other data to inform transportation planning and forming partnerships with other agencies to coordinate efforts.
According to Bhamidipati (2015), climate change aspects can be integrated with transport infrastructure management by incorporating climate risks into asset management models. It allows the assessment of vulnerable areas of the transport network and makes informed investment decisions. The paper suggests that road agencies must be mindful of long-term strategies for capital and maintenance works. Dynamic model simulation can help make decisions among potential alternative strategies. The paper further provides a simulation framework for transport infrastructure management considering climate-change adaptation. The author argues that the framework can help identify the most effective adaptation strategies against climate change-related impacts.
References
Bhamidipati, S. (2015). Simulation framework for asset management in climate-change adaptation of transportation infrastructure. Transportation Research Procedia, 8, 17–28. https://doi.org/10.1016/j.trpro.2015.06.038
de Abreu, V. H. S., Santos, A. S., & Monteiro, T. G. M. (2022). Climate Change Impacts on the Road Transport Infrastructure: A Systematic Review on Adaptation Measures. In Sustainability (Switzerland) (Vol. 14, Issue 14). MDPI. https://doi.org/10.3390/su14148864
Glen Brown, B. B. C. L. A. D. (2018). Climate Change and Asset Management A Sustainable Service Delivery Primer: A companion document to Asset Management for Sustainable Service Delivery: A BC Framework. www.assetmanagementbc.ca.
Kidnie, Murray., Toplis, Caroline., Aecom., & Asociación Mundial de la Carretera. (2015). International climate change adaptation framework for road infrastructure.
Meyer, M. D., Amekudzi, A., & O'Har, J. P. (2010). Transportation asset management systems and climate change: Adaptive systems management approach. Transportation Research Record, 2160, 12–20. https://doi.org/10.3141/2160-02
Meyer, M. D., Flood, M., Sexton, T., Blanchard, B., & Omer, S. (2015). Integrating Extreme Weather Into Transportation Asset Management Plans.
Theuns Henning, S. T. and I. G. (2017). Integrating Climate Change into Road Asset Management. www.worldbank.org
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