Adverse weather conditions are among the main causes of disrupted air travel. It is quite common, in fact, for flights to be delayed or canceled due to severe storms or heavy winds, but higher-than-usual temperatures can also keep planes grounded. Over the last few summers, due to the increasing number of heatwaves, more and more airports around the globe have had to face this issue. In June 2017, for example, over 40 flights were canceled in Pheonix Arizona due to temperatures soaring to a high of almost 49 degrees Celsius. That’s right, sunny days and blue skies do not necessarily translate into perfect flight conditions.
Why extreme heat can disrupt air travel
To understand why airplanes have a harder time taking off in hot weather, let’s take a step back and see how these huge metal birds can fly in the first place. Imagine an aircraft on the runway, ready to boost its engines to maximum power. As the plane speeds across the runway, its wings “split” the air in two: the air flowing above the wings is less dense or contains fewer molecules, while the air flowing below them is denser, hence it contains more molecules. In other words: a lower pressure pushes down the wings, while a higher pressure that lifts them up. It is this difference in pressure that allows the plane to take off smoothly.
As temperature rises, however, the air becomes less dense. In other words, there is less air mass per cubic meter, which implies a lower lift given the same speed of the aircraft. Furthermore, at higher temperatures and lower air density, the engines are less efficient and cannot generate the usual thrust. One solution is for pilots to take off at a higher speed. This, however, can only be accomplished by increasing ground taxiing distances or lowering the aircraft’s take-off weight.
Possible solutions to air travel with global warming
With global warming, caused, among other things, by air traffic emissions, heat waves will become increasingly common and problematic for airports around the world. Smaller aircrafts, featuring less powerful engines will remain on the ground more and more often, and airports with short runways will be forced to relocate or carry out expansion works. One solution would be to shift summer flight departures to early mornings or late evenings when temperatures are cooler.
As reported by Transport & Environment “airplanes burn fossil fuel which releases not only CO2 emissions but also has strong warming non-CO2 effects due to nitrogen oxides (NOx), vapor trails and cloud formation triggered by the altitude at which aircraft operate.” While other sectors have reduced their CO2 emissions, the air travel industry in Europe alone has increased emissions by 28% since 2013. By drastically reducing the number of flights, and by investing in new and more environmentally friendly technologies, airlines could not only contribute to mitigating climate change but perhaps also become more efficient in adverse weather conditions.