Climate change and rising temperatures will impact aircraft takeoffs

Climate change and its effects on many areas have been a hot topic for some time. While the exact effects, and timescales, may be uncertain and continually debated, it is clear that temperatures are rising. This will have an impact on aviation. Existing aircraft and infrastructure are designed with current (or past) climates in mind. If things shift too much, we could see restrictions on aircraft or changes to airports being necessary.

Rising temperatures mean less lift
A key part of climate change and global warming is rising temperature. While the average temperature rise globally (since the pre-industrial period) has been one degree Celsius (based on UK government analysis), actual changes vary around the world. The goal is to keep the average temperate rise to less than 1.5 degrees Celsius – but again this will vary.

What effect will rising temperature have on aircraft? In simplest terms, higher temperature leads to less lift. The higher temperature leads to less dense air, which reduces the lift force on aircraft wings.

Experiencing less lift means that takeoff distance (for the same aircraft weight) is increased. If takeoff distance cannot be increased, aircraft would need to operate under different weight restrictions.

Climate change is affecting wind as well
It is not just temperature that is changing – wind patterns are as well. Research shows that, in general, winds are slowing, and the prevailing direction is changing. A lower wind speed will also affect landing and takeoff distance. With a weaker headwind than experienced before, aircraft will again need longer runway distances or to operate with reduced weight.

This will affect aircraft on the ground. Once in the air, wind changes are different. Climatic changes here are increasing energy levels and generally making in-flight turbulence worse.

Will aviation need to change?
The most likely immediate effect on aviation will be weight restrictions, given the lower lift experienced. There have been several studies carried out into the effects of this. A study by US scientists in 2015 looked at the effects of temperature changes at four major US airports (Phoenix Sky Harbor International Airport (PHX), Denver International Airport (DEN), New York’s LaGuardia Airport (LGA), and Washington Reagan National Airport (DCA)), and the performance impact on the Boeing 737-800. It concluded that rising temperature would cause the number of weight-restriction days between May and September at US airports to increase by 50%–200%.

Another interesting study, based at Greek airports (and using data from the Airbus A320 and DHC-8-400 aircraft), reached similar conclusions. With temperature and wind changes combined, it was estimated that the takeoff distance for a large jet was increasing by about 1.5% every decade. It also noted that aircraft are climbing less steeply after takeoff – increasing pollution and noise disturbance.

Longer-term, there may need to be more significant changes. Operating with weight restrictions is not ideal as airlines and operators seek to maximize capacity and returns. It may even restrict some aircraft at certain airports altogether.

Perhaps future aircraft will incorporate aerodynamic changes to minimize the effect. Such changes have been a significant focus of upgrades and improvements to aircraft over the past decades – mainly though to improve efficiency, maybe manufacturers will also have to take into account changed climate situations in some regions. Changes at airports are also possible. Some runways, of course, could be made longer, but this too is not a simple change and one that will take time. simpleflying.com