Climate change makes everything worse – from the displacement of people from their homeland to an increase in conflict, ill health, and natural disasters. Now, it seems, climate change will take a toll on air travel too.
So perhaps don’t be too swift to yell at the airline industry in the coming decades, as they may be forced to ground more flights as global temperatures continue to rise.
A new study, published in the journal Climatic Change, shows that as temperatures soar, heat waves will become more common and, as a result, flights will be grounded with more frequency.
Extreme heat hinders air travel for a number of reasons, but primarily because it makes it difficult for planes to take-off from the runway. Put simply, warmer air is thinner air, and if outside temperatures become too hot, planes cannot take-off without making an adjustment.
"As air temperatures rise at constant pressure, air density declines, resulting in less lift generation by an aircraft wing at a given airspeed and potentially imposing a weight restriction on departing aircraft," writes study author Ethan Coffel and his colleagues.
To make their predictions, the team from Columbia University constructed performance models for five commercial aircraft and 19 airports around the world. They then made temperature predictions based on emissions scenarios to calculate the percentage of flights that will be affected in the future.
The team found that 10-30 percent of annual flights departing at the time of day when temperatures are highest will be required to reduce their weight or ground flights.
To make the weight restriction, planes may have to offload fuel, cargo, and – yes – even passengers. It also means that planes may need to take on more speed during take-off or use longer runways.
This was seen last month when a record-breaking heat wave struck the southwest United States and grounded dozens of flights. In places like Phoenix, Arizona, temperatures reached the triple-digits, spiking at a blisteringly 49°C (120°F).
While these temperatures mainly impacted some of American Airlines’ smaller jets with less powerful engines, bigger jets will also be affected if temperatures scorch ever higher.
"This points to the unexplored risks of changing climate on aviation," said co-author Radley Horton, a climatologist at Columbia University, in a statement. "As the world gets more connected and aviation grows, there may be substantial potential for cascading effects, economic and otherwise."
The authors estimate that if emissions continue to rise at their current rate, fuel capacities and payload weights will need to be reduced by around 4 percent for certain aircraft on swelteringly hot days. This amounts to roughly 12 to 13 fewer passengers on an average 160-seat craft.
This is a double-edged sword for the aviation industry, as they are one of the major producers of carbon dioxide. Since pre-Industrial times, global temperatures have risen by 1°C (1.8°F), with much of that change occurring after 1980.
Steps can be taken: airlines can make longer runways, schedule flights during cooler temperatures, avoid mid-day heat surges, reduce the number of passenger seats available, and even redesign aircrafts.
In the case of climate change though, let’s not fly away with flights of fancy – it is a real and pressing threat.