Reviewing the impacts of climate change on air transport operations

G B Gratton,A Padhra,P D Williams,S Rapsomanikis

doi:10.1017/aer.2021.109

Abstract

AbstractClimate change is increasing global-mean tropospheric temperatures, but the localised trends are uneven, including cooling the lower stratosphere and lifting the tropopause. The wind speeds are also being modified, both at the surface and aloft. A further effect, additional to wind and temperature alone, is of increasing fluctuations and severity of extreme weather. These are impacting air transport, and this will continue. The effects are known to include increased take-off distances where excess runway lengths exist and reduced payloads where they do not, increased en-route flight times, increased frequency and severity of encounters with clear air turbulence in some regions, changed patterns of wildlife — particularly bird — activity in some regions (potentially also for other anthropogenic reasons) are shifting locations of flight safety hazards, and increased burdens upon airport and associated infrastructure. There is increasing understanding and acknowledgment by companies and authorities of these effects and the importance of mitigating them, although this is not universal and there are as yet no universally understood best practices for air transport climate change mitigation.

Highlights

There is considerable developing understanding that climate change and air transport have a two-way relationship
This remains under study, but climate change is clearly modifying bird population distribution
Dates anecdotally identified include February 14th 2014 and May 28th 2016, and some others have been reported by individual airports or air traffic service providers, but presently there is no central record of these events that would permit extensive analysis

Summary

Introduction

There is considerable developing understanding that climate change and air transport have a two-way relationship. Flight routes and safety advice are based upon known bird behaviours; bird migratory patterns are changing – for example in the Pacific due to El Niño modifying foodsource availability [35], and southern species have been expanding their territory northwards [36]; spring migrations have been occurring earlier in the year [37] This remains under study, but climate change is clearly modifying bird population distribution. At high cruising conditions of km and kts (equivalent airspeed), a decadal decrease of 0.18 ± 0.05% in true airspeed will occur: 2 to 3 minutes increased flight time per 8 h long flight over 30 years, or around a 1% increase This may be assumed additional and independent of the changes due to mean wind changes, such as are described in 2.4 above, and presumably to anything caused by jet stream encounters as described in 2.5

Impact of en-route weather

Findings

Operability of airports and associated infrastructure