Global carbon footprinting data on international aviation emissions aims to support ICAO climate change options

A report examining the global carbon footprint of scheduled international airline passenger operations in 2012 has been published as a data resource to assist deliberations at ICAO on options for addressing the issue of market-based measures (MBMs). Compiled by former Australian government transport official and aviation carbon footprinting expert Dave Southgate, the detailed analysis presents carbon computations by ICAO regions, as well as the highest emitting airlines, airports and countries. The application of MBMs to manage the growth of international aviation emissions has proved a highly complex process. If this debate is to be informed it will be necessary for the participants to have access to carbon footprinting information that allows them to understand the potential impacts of the options under consideration, says Southgate.

The author draws from a number of sources in compiling the information, including data supplied by Innovata, and flight by flight carbon footprints have been computed using a great circle computational tool developed by the Australian government’s Department of Infrastructure and Transport. The algorithms in the tool are based on those contained in the ICAO Carbon Calculator. From 2004 until his retirement in 2012, Southgate was the Australian government representative on ICAO’s Committee on Aviation Environmental Protection (CAEP). He pursued his interest in carbon footprinting while on CAEP and was a member of the group that oversaw the development of the calculator.

Global – international and domestic – carbon emissions from aviation in 2012 are estimated by IATA at 667 million tonnes. ICAO is tasked with regulating just international emissions, making up around 62% of the global total. Southgate calculates the emissions from scheduled international passenger operations to be around 80% of the total carbon footprint of international aircraft operations, or approximately 360 million tonnes.

He says there are significant gaps in solid data available and has therefore been restricted to assessments based on international scheduled passenger operations, albeit by far the largest traffic segment, and the reported carbon data is based on computations.

Southgate is a keen proponent for public access to data and in transparency in environmental decision-making.

“If there is to be an effective response to climate change, decision-makers need to be provided with information that they can understand and trust,” he says in his report. “If there is to be public support for those decisions, members of the public need to be in a position which enables them to understand why decisions have been made and to easily track whether the outcomes of decisions are achieving proclaimed goals.”

He adds that if an international agreement is reached on managing the carbon footprint of international aviation, the establishment of a robust measurement, reporting and verification (MRV) regime will need to be a fundamental part of the decision.

The 184-page report is divided into two parts. Part I is the main body and contains the prime data analysis by region, country, airport, airline and aircraft type, with Part II containing carbon footprint datasheets for the network components.

The data shows up some interesting facts. Three of the seven ICAO regions – North & Central America, Europe and Asia/Pacific – make up about 85% of the global carbon footprint of international passenger scheduled aircraft operations. The top 30 countries in terms of departing operations account for about 80% of the total and the top 50 around 90%.

By airline, Emirates emitted the most CO2 in terms of international passenger aircraft movements in 2012, followed by British Airways, Lufthansa, United Airlines, Delta Air Lines and Air France. By airport of origin, London Heathrow was the highest, followed by Dubai, Hong Kong, Frankfurt, Paris CDG and Singapore. In respect of city-pair routes, emissions were highest between London Heathrow and Singapore, followed by London Heathrow and New York JFK.

Breaking down the carbon footprint of global scheduled international passenger movements by top 10 aircraft types in 2012, operations using the Boeing 777 notched up 23% of total emissions.

Southgate concedes the reliability of efficiency computations is inherently uncertain since, in the absence of detailed information, assumptions have to be made about both load factors and seat configurations across aircraft types of many airlines operating in a range of countries.

Globally the fuel efficiency of aviation has improved at a rate of around 2% per year for the past two decades, calculates the report, while at the same time the carbon footprint has grown at a rate of about 3% per year.
Greenair, May 9, 2013