Climate Impacts of Aviation and the Potential of Aviation Powerfuels Toward Their Mitigation

Abstract

The UN Conference of the Parties, representing nearly all UN member states, agreed in the Paris Agreement to “hold the increase in the global average temperature to well below 2 °C above pre-industrial levels and pursuing efforts to limit the temperature increase to 1.5 °C above pre-industrial levels”. The International Civil Aviation Organization (ICAO) and the International Air Transport Association (IATA) have set a “Net-Zero Carbon Emissions” target by 2050. While the Paris Agreement focuses on limiting global temperature increase, the aviation industry targets primarily address CO2 emissions. However, aviation’s climate impact extends beyond CO2 to contrails and indirect effects of nitrogen oxide (NOx) emissions. Research shows that only one-third of aviation’s climate impact (in terms of effective radiative forcing, ERF) is due to CO2, with the remaining two-thirds from the other non-CO2-related cliamte impacts. The largest climate impacts of aviation, by magnitude, are contrails, CO2 emissions, and NOx effects. Addressing only CO2 emissions would overlook a significant portion of aviation’s climate impact, making it essential to consider all related climate factors to align aviation industry targets with the Paris Agreement. This chapter first describes aviation’s climate effects and then explores how increased use of powerfuels as example for renewably sourced kerosene might influence its overall climate impact.