1Impact of flight altitudes on aviation induced climate change

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Description

Niveau: Supérieur, Doctorat, Bac+8
1Impact of flight altitudes on aviation induced climate change Christine Fichter, Michael Ponater, Robert Sausen, Volker Grewe DLR-Institut für Physik der Atmosphäre, Oberpfaffenhofen, Germany ABSTRACT: The relocation of flight altitudes is a straightforward example how the impact of aviation on climate may be reduced by operational means. However, due to possible trade- offs between the individual climate impact components, dedicated tools have to be developed to enable a swift quantitative assessment of the option of alternative flight routing. We report on current activities to develop such a tool. A comprehensive 3-dimensional (3d) climate model serves to calculate key numbers describing the impact of individual impact components for selected scenarios, while a linear global response model is used to convert these numbers into an overall impact metric for a given flight routing alternative. The approach builds on well-established models, which nevertheless have to be revised, extended, and then optimally combined to address the problem. Keywords: Aviation Climate Impact, Flight Altitude 1 INTRODUCTION Although the aircraft contribution to anthropogenic climate forcing in terms of CO2 emissions is relatively small, the total climate impact of air traffic has been a matter of concern due to several important impact components other than CO2 (ozone, contrails, water vapour and aerosols). Furthermore, aircraft emissions occur in a sensitive area within the climate system, i.

• contrails


• radiative forcing


• only provides


• flight routing


• aviation


• forc- ing changes


• chemistry climate

Sujets

• Contrail (disambiguation)
• Radiative forcing
• Aviation

Informations

• Publié par: profil-zyak-2012
• Nombre de lectures: 15
• Langue: English

Extrait

Impact of flight altitudes on aviation induced climate change

Christine Fichter, Michael Ponater, Robert Sausen, Volker Grewe

 DLRInstitutfür Physik der Atmosphäre, Oberpfaffenhofen, Germany

ABSTRACT: The relocation of flight altitudes is a straightforward example how the impact of aviation on climate may be reduced by operational means. However, due to possible trade offs between the individual climate impact components, dedicated tools have to be developed to enable a swift quantitative assessment of the option of alternative flight routing. We report on current activities to develop such a tool. A comprehensive 3dimensional (3d) climate model serves to calculate key numbers describing the impact of individual impact components for selected scenarios, while a linear global response model is used to convert these numbers into an overall impact metric for a given flight routing alternative. The approach builds on wellestablished models, which nevertheless have to be revised, extended, and then optimally combined to address the problem.

Keywords: Aviation Climate Impact, Flight Altitude

1 INTRODUCTION  Althoughthe aircraft contribution to anthropogenic climate forcing in terms of CO 2 emissions is relatively small, the total climate impact of air traffic has been a matter of concern due to several importantimpact components other than CO 2 (ozone, contrails, water vapour and aerosols). Furthermore, aircraft emissions occur in a sensitive area within the climate system, i.e. the upper troposphere and lower stratosphere. As air traffic is projected to grow very strongly, by about 5% per year up to 2015 (IPCC, 1999), aviation impact may increase more rapidly than that of other anthropogenic emission sectors. One possibility to reduce aircraft climate impact is the optimisation of flight routes, in particular the flight altitude. Aircraft routes and flight altitudes are currently determined by a number of factors including fuel effi ciency and time/air traffic management considerations, but critically environmental impacts are not considered in this process. Previous studies have indicated that the effect of air traffic on the chemical composition of the atmosphere and its impact on global climate depends on the location and the altitude of the emissions (e.g. Fichter et al., 2005; Gauss et al., 2006; Rädel and Shine, 2008; Köhler et al., 2008). Given that the effect of aircraft emissions is criti cally dependent upon external factors (e.g. meteorology, background chemistry), it could be minimized by more sophisticated planning of flight routes and altitudes. However, the indi vidual effects tend to compensate in case of flight altitude shifting: For example, contrails can be avoided by flying at lower, warmer levels within the atmosphere, but this would lead to in creased fuel consumption and CO 2 emissions. We present a comprehensive model framework that is designed to capture the various ef fects in a quantitatively reliable way. We use inventories with globally shifted flight altitudes to estimate the tradeoffs between the most important aircraft climate effects with respect to their altitude and to quantify the net effect. Ways to convert this model framework into a tool of more general applicability (i.e. more sophisticated flight routing optimisation) are de scribed in the concluding section.

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