Airport climate resilience: can we quantify the risks?

Which climate impacts affect airports?

The changing climate prevents a series of challenges to reliable airport operations

In our work helping airports to assess and respond to climate risk, we can foresee several effects of climate change which are likely to become key threats.

These hazards fall into two areas: chronic risks, due slow, sustained changes in weather patterns; and acute risks, based on individual extreme weather events.

The most important chronic risks include:

1. Rising sea levels – Worldwide, most airports are coastal. And their requirement for a large, flat spaces next to major urban areas means they’re often built on low-lying or reclaimed land. As such, airports will be among the first facilities affected as sea levels continue to rise.
   
   
2. Desertification – Lack of water is a challenge too. With extreme heatwaves becoming more common, airports will need to keep operating in times of drought – and to ensure airside staff can work safely and maintain aircraft performance at high temperatures. More airports will need to guard against soil erosion, sand, and dust.
   
   
3. Changing wind direction – Runways are often one-directional, and laid out to give the greatest possible benefit from the prevailing wind. If crosswind shifts by even 20-30 knots the result on operations could be significant.
   
   
4. Subsidence from melting permafrost – In some regions where hard, frozen ground is taken for granted, rising temperatures are already causing significant issues. For example, Greenland’s Kangerlussuaq Airport is facing major repairs after thawing ground caused its runway to collapse.
   
   
5. Changes to local biodiversity – As weather patterns change, wildlife is likely to move too. Some airports will find themselves increasingly prone to strikes from migratory bird species; others could find invasive plant and animal species have a growing impact on airfield maintenance and landscaping.

Meanwhile, acute climate risks are also increasing. Some of the most significant for airport operators include:

1. Storm surges – The coastal location of most airports also makes them especially prone to inundation from storm surges, as extreme weather events become more frequent and intense.
   
   
2. Intense rainfall – The high surface area of a typical airfield means even a short, intense rain shower can leave the airport needing to quickly drain or buffer billions of litres of rainwater. Climate change will change precipitation patterns, and make managing such cloudbursts a key requirement at many locations.

More frequent lightning – Being located by the sea makes many airports disproportionately likely to be affected by lightning as weather systems become more dynamic and unstable. Flight cancellations for safety reasons could therefore become more frequent.

Chronic shifts and acute weather hazards are both important when building a roadmap to keep an airport operational as the climate changes. It’s worth remembering that, while a storm might pass through in a few hours, solving the resulting issues might take weeks or even months.

Obstacles preventing airport climate resilience

Climate change is a slow-moving, global issue – meaning airports struggle to respond

Despite these growing threats, climate resilience has so far remained a relatively low priority for many airports.

At NACO, we worked with the Civil Aviation Authority of Singapore (CAAS) to benchmark preparations for climate change at the country’s Changi and Seletar airports. We found that, typically, operators only prioritised resilience measures after experiencing an extreme weather event elsewhere in their airport portfolio.

This reluctance to work proactively – unless there’s been a major event – perhaps explains why airports have focused elsewhere. Faced with regulatory and public pressure to address emissions, noise, and other immediate problems, their slowly growing exposure to climate risks may lack the urgency to top the agenda at any given moment.

Also, climate-related challenges usually affect entire regions. This means there can often be interdependencies between issues, and the best solution might need the airport operator to work collaboratively with the surrounding community. For example, our water management work for Schiphol Airport complements wider, national flood protection.

While this kind of collaborative approach can maximise the investment and impact achieved, involving multiple stakeholders also makes the project more complex – which some might see as a deterrent.

Quantifying airport climate risk

Another key obstacle is the difficulty of turning the mass of climate data into a clear, compelling business case. Before climate resilience can become a priority, airport operators need a credible way to assess – and communicate – the risk.

Understanding hazard exposure based on the climate today – and in the near-term future – is relatively straightforward, thanks to digital tools like Twinn Climate  Intelligence App.

Historical and real-time data can be integrated and visualised to give a clear view of risk, and model likely scenarios for slow, chronic climate effects.

Forecasting future exposure to extreme weather events is more challenging. Models rely on historical data and, as the kind of change we’re seeing to weather systems has never happened before, climate scientists have no precedent to refer to.

Instead of detailed predictions, therefore, we base our long-term roadmaps for airport resilience around a balance of probabilities. This scenario analysis approach allows us to explore alternatives for what might happen in the future, and understand what will drive those events.

We can model possible outcomes based on a range of severities – and understand what would happen in best and worst-case scenarios. Which assumptions the operator will use depends on the strategic importance of the airport, and their own attitude to risk.

As climate-related disruption becomes more frequent still, it seems likely that investors will take a keen interest in this position – and the risk profile carried by airport operators worldwide.

Even in the absence of public or regulatory pressure, there will be a growing number of questions to be answered – making climate resilience planning more of a priority. Change is coming, and good quality data and disclosure will be absolutely key.