Enabling resilient railway operations in the context of climate change

As a relatively environment-friendly transport mode, railways have a valuable role to play in mitigating anthropogenic climate change. However, this can only be achieved if railways can adapt to withstand the effects of the increasingly extreme weather associated with climate change. The primary challenge lies in protecting infrastructure from flooding, sea level rise, the effects on earthworks of heavy rainfall and/or drought, buckling of rails in extreme heat and the effects of lightning strikes on signalling systems. This challenge is exacerbated by the extent of railway networks, by the adaptation costs and the variable levels of vulnerability, and by the uncertainties associated with future climate conditions and traffic volumes and values. This emphasises the need for a systematic approach to adaptation, to ensure that the work undertaken is organised and scheduled to maximise the potential benefits arising from the limited funds and resources available. This paper proposes a framework for the segmentation of a railway network, assessment of the economic value of traffic using the network (and thus the economic costs of weather-related disruption), assessment of vulnerability of different segments of the network to the effects of climate change, identification of appropriate remedial measures and their costs, and their prioritisation by means of cost-benefit analysis. The proposed approach provides a comprehensive, prioritised approach to climate change adaptation, reflecting current and anticipated traffic and infrastructure vulnerability, and the varying costs and benefits of different intervention types. Proposed interventions can be prioritised by ranking them in descending order of Benefit-Cost Ratio.