Tomorrow's Railway and Climate Change Adaptation Final Report

Stakeholder workshops and other stakeholder engagement activities have highlighted
the need for increased spatial and temporal resolution for rainfall information in
particular. This would allow the development of better vulnerability mapping
techniques. It could potentially lead to more accurate rainfall risk assessment and
prediction tools.
An analysis for future frequency and intensity of rainfall would be a useful comparison
both at the system level and for many different asset classes. However, this would be
dependent on the baseline sensitivity of assets, sub-systems and the whole system to
rainfall first being quantified at an appropriately high resolution.
Appropriate flooding alerts will be location specific. However, flooding at a given
location will impact many asset classes at once. Therefore an understanding of how
flood risk is projected to increase across the country and beyond the land owned by
Network Rail is likely to be of benefit.
Analysis of the future frequency at which a range of wind speeds may be exceeded has
already been undertaken during T925 [92]. Whether further work would be useful both
at the system level and/ or for different sub-systems, asset classes and locations would
depend on being able to characterise existing wind sensitivities appropriately.
An analysis of the future frequency of snowfall would be useful at both the system level
and for many different sub-systems and asset classes. To some extent this is covered by
the UKCP09 technical note on snow [480]. However, appropriate consideration of the
caveats to this report would be required, as would any known sensitivities of particular
locations and assets to snow.
3.1.4 Monitoring and measurement of assets
In general, an enhanced programme of vulnerability mapping for all assets and locations
would be a useful exercise. By way of example, Network Rail holds a critical rail
temperature (CRT) register of locations which are particularly sensitive to track buckling,
and this is consulted as part of the management of track buckling risk. The development
of similar registers for other assets, sub-systems and/ or for other weather and climate
variables is encouraged.
It is recommended that the industry develops methodologies for the collection of data
relating to trees, vegetation and adjacent land. Better understanding of sites vulnerable
to high winds can then be fed into both design and operational procedures for managing
leaf, branch and tree fall.
A threshold-based approach is not necessarily the best one for lightning risk, as an
electrical storm forecast does not necessarily mean a bolt of lightning will strike the
railway or cause damage. Once impacts of lightning strikes have been studied further,
we can get a better understanding of whether a threshold based approach is relevant
and, if so, what type of analysis is needed. An appropriate use of near-real time lightning
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