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Projecte llegit

Títol: Analysis of the Trend of CAT (Clear Air Turbulence) over Europe

Estudiants que han llegit aquest projecte:

Director/a: MAZÓN BUESO, JORDI

Departament: FIS

Títol: Analysis of the Trend of CAT (Clear Air Turbulence) over Europe

Data inici oferta: 20-01-2025     Data finalització oferta: 20-09-2025


Estudis d'assignació del projecte:
    GR ENG SIST AEROESP
Tipus: Individual
 
Lloc de realització: EETAC
 
Segon director/a (UPC): PINO GONZÁLEZ, DAVID
 
Paraules clau:
CAT, Europe, trend, climate change
 
Descripció del contingut i pla d'activitats:
Turbulence, and in particular clear air turbulence (CAT), is one of the causes of delays and economic losses for airlines (e.g., Kauffmann, 2002; Sharman, 2016), as well as being a source of discomfort and incidents for passengers, which can lead to physical injuries (Williams, 2017; Kharoufah et al., 2018). There is evidence that clear air turbulence (CAT) on transatlantic flights between Europe and the United States has increased due to global warming (e.g., Storer et al., 2017 and 2019; Williams et al., 2013). The proposed study aims, first, to examine the nature of these turbulences and how global warming can modify their intensity and location over the European continent. Secondly, by searching through various databases related to CAT formation, the study will analyze the trend of these turbulences in recent decades on flights over Europe. Several flight routes and altitudes crossing the continent will be analyzed, including those where these types of turbulences are more frequent.
 
Overview (resum en anglès):
Clear Air Turbulence (CAT) is a significant hazard in aviation because it is often encountered unexpectedly and might provoke violent changes in vertical velocity. It is a risk to passenger safety and operational efficiency. Previous studies have predicted an increase in its severity and frequency due to climate change. While these articles have mostly focused on North America and the North Atlantic, this work examines CAT trends over Europe between 1994 and 2024.
Using ERA5 reanalysis data at 200 and 225 hPa pressure levels, variant 1 of the Ellrod Index (EI1) is used to assess CAT at cruise altitudes. Aiming to evaluate the trend, different analyses have been conducted. Annual averages along all years have been plotted and, after that, the domain has been divided into northern and southern regions for more detailed insights. These results have also been analysed separately depending on the seasons. Finally, following the methodology in Prosser et al. (2023), the probability of encountering Moderate-Or-Greater (MOG) turbulence has been computed.
Results do not show a clear long-term increase in CAT across Europe, like it is predicted in other areas of the planet. However, southern latitudes have higher EI1 values and greater variability. Seasonally, spring shows a decreasing tendency while autumn indicates a rising tendency, regardless of the region. When it comes to summer and winter, the trends depend on the area considered. The MOG exceedances analysis reveals a 38.6% relative increase, with an absolute change of 0.004%/year, but presenting a notable dispersion.
In summary, although no strong overall CAT increase is detected in Europe, regional and seasonal trends suggest potential areas of concern. For this reason, a continued monitoring and improved forecasting is crucial to avoid CAT and its hazards while flying.

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