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Research Fellows Directory

Paul Williams

Dr Paul Williams

Research Fellow


University of Reading

Research summary

One of my research interests is atmospheric turbulence and its impacts on aviation. Commercial aircraft encounter moderate-or-greater turbulence tens of thousands of times each year worldwide. These encounters injure hundreds of passengers and crew, cost airlines tens of millions of dollars, and cause structural damage to planes. Clear-air turbulence is especially difficult to avoid, because it cannot be seen by pilots or detected by satellites or on-board radar. Clear-air turbulence is linked to jet-stream wind shears, which are projected to be strengthened by anthropogenic climate change. However, the consequences of climate change for clear-air turbulence have only recently been recognised.

My research has used climate model simulations to show that clear-air turbulence changes significantly within the transatlantic flight corridor when the concentration of carbon dioxide in the atmosphere is doubled. At cruise altitudes within 50-75N and 10-60W in winter, most clear-air turbulence measures show a 10-40% increase in the median strength of turbulence and a 40-170% increase in the frequency of occurrence of moderate-or-greater turbulence. These results suggest that climate change will lead to bumpier transatlantic flights by the middle of this century. Journey times may lengthen and fuel consumption and emissions may increase. Aviation is partly responsible for changing the climate, but these findings showed for the first time how climate change could affect aviation.

Interests and expertise (Subject groups)

Grants awarded

Numerical and parametric errors in weather and climate models

Scheme: University Research Fellowship

Dates: Oct 2014 - Sep 2017

Value: £273,101.01

Improving predictive climate models through stochastic parameterization

Scheme: University Research Fellowship

Dates: Oct 2009 - Sep 2014

Value: £466,448.85