Global aviation CO2 emissions are rising 70 per cent faster than ICAO projections, finds ICCT
A new fleet of Airbus A320neo aircraft helped Frontier top ICCT's US domestic fuel efficiency ranking
Thu 19 Sept 2019 – Analysis by the International Council on Clean Transportation (ICCT) shows global CO2 emissions from commercial aviation are currently rising 70% faster than long-term projections by ICAO that already point to a tripling of emissions by mid-century. ICCT has carried out what it claims is the first detailed global CO2 inventory for aviation in 15 years and finds that total emissions from all commercial operations, including freight, totalled 918 million tonnes (Mt) in 2018, around 2.4% of the global total. This is close to the industry’s own estimates of 905 Mt reported in June, which was a 5.2% increase over the previous year. The ICCT data shows 40% of global passenger transport-related CO2 emissions came from domestic flights, which are outside the scope of ICAO’s global CORSIA scheme. ICCT has also released its latest US domestic airline fuel efficiency rankings that found Frontier Airlines to be the most efficient in the 2017-18 period.
ICCT says using IATA estimates, CO2 emissions from commercial flights have increased 32% over the past five years from the 694 Mt emitted in 2013, implying an annual compound growth rate of 5.7%. ICAO projects a 2.2 to 3.1-fold increase in CO2 from international aviation (therefore excluding domestic aviation) from 2015 to 2045, or a 2.7% to 3.9% annual compound growth rate, depending on assumptions about fuel-efficiency gains.
ICCT calculates passenger transport accounted for 747 Mt, or 81%, of global aviation emissions in 2018, and emitted four times as much CO2 as freight transport, so has focused most of its study on passenger operations. Globally, two-thirds of all passenger flights in 2018 were domestic, accounting for one-third of global RPKs (revenue passenger kilometres) and a large majority of departures in a number of countries, including Brazil (92%), the United States (91%), China (91%), Indonesia (89%) and Australia (86%).
Flights within the Asia/Pacific region in 2018 emitted the largest share of passenger transport-related CO2 at 25% of the global total, or 186 Mt. Collectively, the 28 members of the European Union accounted for 142 Mt from passenger transport, or 19% of the global total. Intra-EU flights emitted an estimated 67 Mt of CO2, or 9% of the global total. The five countries with the highest CO2 emissions from passenger transport by departure were the United States (182 Mt, 24% of total CO2), China (94.9 Mt, 13%), United Kingdom (29.8 Mt, 4.0%), Japan (23.4 Mt, 3.1%) and Germany (22.2 Mt, 3.0%).
Carbon intensities by route group were also investigated by ICCT. The least efficient route groups – flights within the Middle East and within Africa – were found to have emitted over 30% more CO2 to transport one passenger one kilometre than the worldwide average in 2018. High-income countries were responsible for 62% of CO2 emitted from passenger aircraft. Overall, less developed countries that contain half of the world’s population accounted for only 10% of all passenger transport-related aviation emissions.
To compile the inventory, ICCT used multiple public data sources and merged to quantify the amount of fuel burned and therefore CO2 emitted, using aircraft performance and design software. ICCT said for future updates it intends to identify better data sources to improve its analysis of air freight and expand its work on model validation, particularly for domestic operations, using international, national and airline-level data. It also expects to include projected emissions in its reports.
ICCT has been ranking US airlines for fuel efficiency on domestic routes since 2010 and, for the first time, Alaska Airlines has been replaced as the most fuel-efficient carrier by Frontier Airlines in its 2017-18 rankings. Its large investment in new, more efficient Airbus A320neo aircraft has enabled Frontier, which calls itself America's greenest airline, to improve the fuel efficiency of its fleet by almost 4% from 2017 to 2018 through new deliveries, according to ICCT. It also flew more direct routes and with more passengers per flight than almost all of its peers. Spirit and Southwest, its closest competitors both burned 7% more fuel on comparable flights. The worst-ranked carrier, JetBlue, burned 26% more fuel than Frontier on comparable flights, which ICCT mostly attributes to lower seating densities.
Overall, ICCT found CO2 emissions from US flights are continuing to expand rapidly, with traffic increasing three times as fast as improvements in fuel efficiency. From 2016 to 2018, it says passenger miles increased 10%, fuel efficiency improved 3% and overall fuel use rose by 7%.
Global CO2 emissions in 2018 by operations and aircraft class (source: ICCT):