Heavy rains and storms very much characterized the second half of 2019. Across Europe, lines, roads, and villages were flooded and rail services were knocked out. In the future, weather forecasts will become even more unpredictable and extreme weather will most likely become the new normal. How will this impact our railways and what measures can we take to prepare ourselves for a more unpredictable future?
Who turned up the temperature?
According to the World Meteorological Organization, 2019 was the second hottest year on record after 2016. Since the 1980s, every decade has been warmer than the last one. Average temperatures for the five-year (2015–2019) and ten-year (2010–2019) periods were the highest on record. Record levels of heat-trapping greenhouse gasses have caused our climate to change, and this trend is therefore expected to continue in the future (UN Environment Program (n.d.)).
During periods of high temperatures, rail can reach up to 20°C above air temperature when in direct sunlight. When exposed to high temperatures, the rail expands and is subjected to strong compression. This increases the risk of derailment and causes major performance and safety issues for rail operators.
Storms & heavy showers
Storms and floods are not unusual and occur seasonally. However, their intensity has increased which suggests that adverse weather will likely only worsen as the global average temperature rises (Berti, A. (2020)).
Powerful storms and increased wind speeds can have financial and traffic-related consequences for railways as the overhead wires are vulnerable to higher wind speeds. Storms are often accompanied by heavy rain. This can cause groundwater levels to rise and increase the risk of erosion of railway cuttings. Heavier showers can also be quite the challenge for the railway drainage system. A clogged drainage system may cause water to intersect the railway line and thus further increase the risk of erosion. Problems with the drainage system can also cause unintended movements of the track.
Uncertainty calls for action
With hotter summers, snowier winters, and mid-seasons rainier and stormier, it has become almost impossible to predict the weather. This makes it difficult for the industry to safeguard themselves when extreme weather strikes.
Uncertainty calls for action, but how can the industry prepare for an unpredictable future? A key starting point could be to make the existing infrastructure more resilient. Most earthworks, soil- and rock cuttings and embankments are more than 150 years old. Their vulnerability becomes apparent after prolonged periods of wet weather or more intensive short duration rainfall events. This can cause washouts or trigger slips and failures that affect the safety of the railway. Modernizing the existing infrastructure, thus making the structures more resilient, could minimize the risk.
New technology has made it possible to innovate maintenance on existing lines. Drones and remote monitoring solutions can be applied to identify lurking issues. This will enable rail operators to carry out repairs before any potential failures have time to evolve into something critical. To prevent accidents on the railway following heavy downpours, early warning systems could also be pivotal. In the event of any problems, the early warning system can shut down the train service. Additionally, a recent EU project has found that optical and radar satellites could be highly beneficial in preventing future floods(Berti, A. (2020)).
Preparations for an unpredictable future
Artificial intelligence, machine learning, and data science can be used to optimize the maintenance strategy and to develop increasingly efficient response strategies. With the help of sensors, cameras, or lasers, the rail network can be monitored from behind a desk.
By making the existing infrastructure more resilient and by using the latest technologies and measures, rail operators can protect their rail network from the impacts of climate change. It is difficult to predict the future. However, with the right measures and innovative thinking, it will be easier to prepare our railways for the unpredictable.
- UN Environment Program (n.d.). Who turned up the temperature? Climate change, heatwaves and wildfires
- Berti, A. (2020). The eye of the storm: boosting railway resilience in the UK
- Burroughs, D. (2019). Building for a changing climate