Suchergebnisse

Impacts of commercial aircraft operation upon the environment, which are caused primarily from emissions of CO2, NOx and the formation of contrails, are matter of growing concern, as aviation is one of the fastest developing industrial sectors worldwide and the awareness of its effects is expanding. Recent research has focused on the cost-benefit potential of different mitigation strategies, which optimize flight trajectories with respect to climate and economy, but most of these mitigation strategies cannot be implemented in the near future due to technical challenges. The objective of this paper is to present an interim mitigation strategy, which bridges this time period. In analogy to military exclusion zones, climate restricted airspaces (CRA) are defined based on 3-D climate change functions, characterizing the environmental impact caused by an aircraft emission at a certain location. Regions with climate costs greater than a threshold value are closed in the corresponding month; others are cleared for air traffic. To estimate the cost-benefit potential of this strategy, a preliminary analysis is conducted on the route from Helsinki (EFHK) to Miami (KMIA). Affected flight trajectories are re-routed optimally around resulting CRA with regard to monetary costs for varying threshold values. Therefore, flight simulation algorithms are developed, which solve a non-linear optimal control problem. For each optimized flight trajectory corresponding average temperature response (ATR) and cash operating costs (COC) are expressed relative to a reference great circle trajectory with constant Mach number and compared with the climate mitigation potential of climate optimized trajectories.

In order to achieve a reduction in non-CO2 effects, the European Parliament (EP) voted on June 8, 2022 to expand the scope of the EU Emissions Trading System (EU ETS) (EP, 2022). In December 2022 the European Council, the European Commission (EC) and the EP reached an agreement on the revision of the EU ETS. According to the agreement, non-CO2 effects can no longer be ignored and the EC should set up a monitoring, reporting and verification (MRV) scheme for non-CO2 aviation emissions from 2025, as a first step for the full integration of non-CO2 effects into the EU ETS. This project focuses on the development and testing of such an MRV system. For this purpose, non-CO2 effects are integrated according to the principle of equivalent CO2 emissions (CO2e). Since several CO2e calculation methods are in principle available, the selection process involves a trade-off between the level of atmospheric uncertainties, the level of climate mitigation incentives, and the resulting effort of MRV activities (see Section 1.2). In the present report we take over the perspective of an aircraft operator and analyze all necessary tasks for monitoring and reporting of location-dependent CO2 equivalents. For this purpose, we use flight monitoring data from 400 intra-European flights, which were provided by the European Air Transportation Leipzig (EAT) (see Section 2). To keep the MRV effort as low as possible, most monitoring and reporting steps are automated via a software tool that might be provided or approved for the users by the EC (see Section 3). In the case of location-dependent CO2 equivalents, the standardized CO2e software includes the emission calculation (CO2, H2O, NOx) along the flight route (see Section 3.1) as well as the estimation of the CO2e factor of the flight (see Section 3.2). Exemplary results are discussed in Section 4. We show some possible steps forward for integrating non-CO2 effects into the EU ETS and formulate recommendations for an MRV scheme of non-CO2 effects.

In order to achieve a reduction in non-CO 2 effects, the European Parliament (EP) voted on June 8, 2022 to expand the scope of the EU Emissions Trading System (EU ETS) (EP, 2022). In December 2022 the European Council, the European Commission (EC) and the EP reached an agreement on the revision of the EU ETS. According to the agreement, non-CO 2 effects can no longer be ignored and the EC should set up a monitoring, reporting and verification (MRV) scheme for non-CO 2 aviation emissions from 2025, as a first step for the full integration of non-CO 2 effects into the EU ETS. This project focuses on the development and testing of such an MRV system. For this purpose, non-CO 2 effects are integrated according to the principle of equivalent CO 2 emissions (CO2e). Since several CO2e calculation methods are basically available, the process of selection involves a trade-off between the level of atmospheric uncertainties, the level of climate mitigation incentives, and the resulting effort of MRV activities (see Section 1.2). In the present report we take over the perspective of an agency and analyze all necessary tasks for the verification of reported location-dependent CO 2 equivalents (Input of Task 1). To reduce the additional MRV effort to a minimum, all necessary CO2e validation steps should automatically be performed by a standardized CO2e software, possibly provided directly by the EC or by an approved organization. This includes the query and processing of 4-D flight profile data from an independent data source, the verification of the reported CO 2 (fuel burn), the estimation of fuel flow and non-CO 2 emissions along the flight path, and the estimation of equivalent CO 2 emissions per flight. Analogous to the CO 2 monitoring in EU ETS and under CORSIA, different computation methods can be made available for the physical-based modules. The selection of the calculation methods used by an individual aircraft operator should be specified in the airline specific Emission Monitoring Plan (EMP) and submitted to the competent authority for approval. The allocation of the level of CO2e surrender obligations is a political decision and not part of this project.

In addition to CO2, aviation affects the climate through other emissions and atmospheric processes, such as the formation of ozone and contrail cirrus. These non-CO2 effects account for about 2/3 of aviation's total climate impact but can vary widely from flight to flight. Although scientists have complex models to determine the climate impact of individual flights, there was no simple tool for the public to estimate this relatively accurately and quickly. In this project a user-friendly Excel application has been developed that provides an estimation of the climate impact of a single flight that is much more detailed than a simple constant factor. Users simply need to enter the origin and destination of the flight and the aircraft size category.

Although about two-thirds of aviation's climate impacts are caused by non-CO2 effects, such as ozone production or contrail cirrus formation, these effects are not yet considered in existing and currently planned policy instruments (e.g. EU ETS or CORSIA). Due to their climatological relevance, however, various economic concepts have been proposed recently to internalise nonCO2 effects. Most of these approaches are based on the principle of equivalent CO2 emissions (CO2e), a way of unitizing the impact of all climate agents. Several calculation methods for CO2 equivalents are in principle available, which differ in the degree of detail and are subject to uncertainties related to atmospheric science. There are a quite a few key decision parameters for policy makers for setting up a monitoring, reporting, and verification (MRV) scheme for non-CO2 effects. The aim of this study is therefore to analyze and discuss the most important decision parameters for the integration of non-CO2 aviation effects into EU ETS.

Aircraft operations contribute to climate change by emissions of carbon dioxide (CO 2), nitrogen oxides (NOx), sulfur oxides (SOx), water vapor (H 2O), aerosols, and the formation of contrails and contrail cirrus. Since 2012, aviation's CO 2 emissions have been regulated by the European Emission Trading System (EU ETS). All flights within the European Economic Area (EEA) are subject to this scheme. According to Article 30(4) of the revised EU ETS Directive 2018/410, 'the Commission shall present an updated analysis of the non-CO2 effects of aviation, accompanied, where appropriate, by a proposal on how best to address those effects (before January 2020).' Against this background, the EU Commission commissioned a study to EASA in 2019. Three main questions had to be investigated: Question 1: What is the most recent knowledge on the climate change effects of non-CO2 emissions from aviation activities? Question 2: What factors/variables have had an impact on those effects? What is the level of that impact? Do these factors/variables exhibit trade-offs or interdependencies between different emissions? Question 3: What research has been undertaken on potential policy action to reduce non-CO2 climate impacts? What are the pros and cons of these options in terms of implementation? What knowledge gaps exist?' As of November 2020, the full report investigating these tasks has been published (European Commission, 2020). In December 2020, the German Environmental Agency (UBA), mandated the German Aerospace Center (DLR) with a study on proving/testing monitor ing and reporting methods for non-CO2 climate impacts of aviation in the EU ETS. One important work package within this DLR-study was the review of the EASA study by the European Commission (2020). This review has been conducted with the emphasis on currently remaining research questions, on a risk management analysis and on measures implementable as pilot project(s). The main results of this review are presented in this report.

Although about two-thirds of aviation's climate impacts are caused by non-CO2 effects, such as ozone production or contrail cirrus formation, these effects are not yet considered in existing and currently planned policy instruments (e.g. EU ETS or CORSIA). Due to their climatological relevance, however, various economic concepts have been proposed recently to internalise non-CO2 effects. Most of these approaches are based on the principle of equivalent CO2 emissions (CO2e), a way of unitizing the impact of all climate agents. Several calculation methods for CO2 equivalents are in principle available, which differ in the degree of detail and are subject to uncertainties related to atmospheric science. There are a quite a few key decision parameters for policy makers for setting up a monitoring, reporting, and verification (MRV) scheme for non-CO2 effects. The aim of this study is therefore to analyze and discuss the most important decision parameters for the integration of non-CO2 aviation effects into EU ETS.

In addition to carbon dioxide, air traffic operation affects the climate through other emissions and atmospheric processes, such as the formation of ozone and contrail cirrus. The climate impact of these non-CO2 effects is strongly dependent on the emission location (in particular cruise altitude) and emission time (e.g. weather conditions) and, thus, highly non-linear to the fuel consumption. Although non-CO2 effects are responsible for about 2/3 of the climate impact of aviation, they are not yet taken into account in existing and currently planned emissions trading systems (e.g. EU ETS) or market-based measures (MBM, e.g. CORSIA 1). This research project focuses on the development of concepts for the integration of non-CO2 effects of air traffic into the EU ETS and under CORSIA. For this purpose, suitable climate metrics for assessing the relationship between non-CO2 and CO2 climate impacts are analyzed first (Part A). For selected non-CO2 calculation methodologies, the availability of the necessary data is examined and estimation procedures for non-existent data are investigated (Part B). Afterwards, the current practice in voluntary carbon markets for estimating CO2 and non-CO2 effects of aviation is presented (Part C). The additional administrative burden to verify reporting on aviation's non-CO2 is examined in Part D. In the final step, key design parameters for the integration of non-CO2 consequences of aviation in the EU ETS and CORSIA are evaluated (Part E). The inclusion of non-CO2 effects in the EU ETS and CORSIA is highly recommended for climatelogical reasons and technically feasible, but involves an additional administrative burden for authorities and aircraft operators. The level of the resulting mitigation incentive as well as the additional effort is strongly depending on the calculation methodology of the CO2 equivalents. For this choice, a trade-off must be made between a simple operational feasibility and a high incentive level to modify flight routing and to reduce the NOx emission indices. False mitigation incentives, which can arise from to the non-linearity between non-CO2 climate effects and fuel consumption, must be prevented.