myclimate experts review the calculation principles behind our emissions calculators at regular intervals. With the help of current scientific studies (Lee et al. 2021, Swiss Academy of Sciences (SCNAT) 2021) and data from the aviation industry, the popular flight calculator has now undergone an update. The last update was back in 2019. In general, the myclimate flight calculator is based on and meets the current European standard for transport, (DIN) EN16258.
The most important adjustments to the calculation principles behind the myclimate flight calculator at a glance:
- The RFI (Radiative Forcing Index), which expresses the ratio of the climate impact of all climate-impacting effects of air travel as a multiplier of CO2 emissions, has been increased from 2 to 3.
- Premium Economy class has been added.
- A selection of ten of the most common short- and long-haul aircraft types flown in Europe and globally have been added.
What exactly does this mean?
Based on current studies (Lee et al. 2021, SCNAT 2021), myclimate has decided to increase the RFI from 2 to 3. “Non-CO2” effects are caused, for example, by the short-term increase in tropospheric ozone as a result of nitrogen oxide emissions (NOx), the contrails produced and the possible formation of cirrus clouds as a result. The studies in question recommend this factor in order to map the entire climate impact of air travel in CO2 equivalents when considering a time horizon of 30 years, which is essential for achieving the net-zero target by 2050. The adjustment now gives the historical impact and the shorter-term effects additional weighting. This means they meet the myclimate guidelines for calculating climate impact and are now taken into account when calculating the overall climate impact of flights. As a result, the myclimate flight calculator also consistently accounts for the net-zero target (2050).
In addition to the adjustment to the RFI, a new seat class is now available for selection: Premium Economy. This means that the following four seat classes are now available to users in the updated myclimate flight calculator: Economy, Premium Economy, Business and First Class. The better the seat class, the more space a passenger takes up on the aircraft and the fewer passengers can be transported.
The third major change in the new flight calculator is the ability to specifically enter each type of aircraft used. This means that actual flight emissions can be calculated with even more customisation, if desired. The ten most common aircraft types in European and global air traffic can be selected. If the aircraft type is not known or not listed in the flight calculator’s drop-down menu, the climate impact can be calculated as usual using the stored average standard data for short- and long-haul flights.
Calculation principles behind the flight calculator
How does this affect the results of the calculated climate impact?
In particular, increasing the RFI to a factor of 3 has a decisive influence on the level of the calculated climate impact. In the previous versions of the myclimate flight calculator, the RFI factor was set to 2 based on the sources available at the time. myclimate is aware that the use of this factor can only serve to estimate the relationship between CO2 emissions and overall climate impact.
At the same time, the updated data for aircraft fleets lead to a comparative reduction in flight emissions due to more modern and efficient technology in this calculation sector.
For example, the CO2 emissions for a return flight from Zurich to New York JFK Airport in Economy class have increased from 2.0 tonnes in the previous version to 2.3 tonnes in the current flight calculator.
“With our online calculators, we endeavour to make tools freely available that are able to make the most accurate statements possible on the climate impact of certain activities in a user-friendly way. The new version of the flight calculator maps individual flight scenarios even more accurately and puts their impact in clear relation to the net-zero targets. We are convinced that the resulting tool can offer interested private individuals and corporate customers an accurate, state-of-the-art and easy-to-obtain calculation of the climate impact of flights,” says Martin Lehmann, the myclimate expert responsible.
The project was planned and implemented at myclimate under the leadership of Martin Lehmann, Senior Consultant for Footprint Analysis, Alina Schmidt, Consultant for Product Solutions, and Maren Heltsche, Senior Web Developer.
Link to the myclimate flight calculator (English)
https://co2.myclimate.org/en/flight_calculators/new
Link to detailed information about the calculation principles
The myclimate flight calculator
Selection of sources used in the creation of the flight calculator
IATA 2023: Passenger CO2 Calculation Methodology. https://www.iata.org/
Lee et. al. (2021): The contribution of global aviation to anthropogenic climate forcing for 2000-2018. Atmos. Environ. 244 117834.
scnat (2021): The impact of emissions from aviation on the climate. Swiss academies communications. Vol. 16, No.3, 2021.