Model 8: Airports (IC601010)

The TICCS subclass IC601010 (airports) describes the assets in this model. For Scope 1 and 2 emissions, we apply RBMs based on 14 regressors, including reported emissions for 100+ assets, assets’ physical characteristics using publicly available geospatial data, local temperatures from satellite data (Copernicus), the number of passengers (WikiData), and information on nearby power plants to differentiate between Scope 1 and Scope 2 emissions (WRI, 2021).^[1]

We model Scope 1 and 2 emissions in tons of CO2e based on separate functions of physical characteristics, temperature, number of passengers, proximity to power plants (that produce electricity for the airport), and other observations. We include the best combination of multiple regressors while minimising the number of variables to maximise the coverage of assets to predict emissions.^[2]

For Scope 3, we apply an ABM using commercial air traffic data at the single flight level and the assets’ geolocation based on publicly available geographic databases. For the air traffic data, we model emissions from cruise – the period in the air between the ascent and descent phase of an aircraft’s flight – and landing and take-off (LTO) cycle, based on official fuel and emissions data provided by the International Civil Aviation Organization (ICAO, 2023) and the European Monitoring and Evaluation Programme (Winther & Rypdal 2019). Hence, we estimate Scope 3 emissions based on the following:

With:

Where nm represents nautical miles and GCD great circle distance. The sum (…) is calculated for each flight i departing from a given airport.

And:

Where contributions from departing and arriving flights represent the first and second parts of this equation, respectively. The contribution is obtained as follows:

Here, provides the full contribution of the LTO cycle for a given aircraft type based on the available data (ICAO, 2023; Winther & Rypdal, 2019) and assuming standard times for the LTO cycle phases. The sum represents the ratio of products from the aircraft engines' thrust f^p and duration T^p during phase p in the LTO cycle. As for the departure and arrival phases of the LTO cycle, they refer to taxi-out, take-off, and climb-out for the departure, and approach-and-landing and taxi-in for the arrival.

_{[1] We assume that power plants in direct proximity to the airport belong to the airport asset. Hence, carbon emissions related to electricity usage would fall under Scope 1, not Scope 2 emissions.}

_{[2] More details about the modelling approach for airports can be found in Nugier et al. (2022). The model precision has been improved since the first publication, including better control over variables and updated access to reported emissions.}

_{ICAO (2023). ICAO Carbon Emissions Calculator Methodology. Version 12.}_{International Civil Aviation Organization}_._{https://applications.icao.int/icec/Methodology%20ICAO%20Carbon%20Calculator_v12-2023.pdf}

_{Winther, M., & Rypdal, K. (2019). EMEP/EEA air pollutant emission inventory guidebook 2019. European Monitoring and Evaluation Programme.}_{European Environment Agency}_._{https://www.eea.europa.eu/publications/emep-eea-guidebook-2019/part-b-sectoral-guidance-chapters/1-energy/1-a-combustion/1-a-3-a-aviation}

_{WRI (2021). Global Power Plant Database V1.3.0.}_{World Resource Institute}_._{https://datasets.wri.org/dataset/globalpowerplantdatabase}