ICAO Standards and guidance material on environmental issues are always founded on scientific consensus. As a consequence, in support of a data-driven decision making process, ICAO is constantly monitoring the evolution of scientiﬁc knowledge related to the impacts of aviation on the environment.
This is in line with provisions from the ICAO Resolution A40-17 (2019), where the ICAO Assembly invites States and international organizations to provide the necessary scientific information and data to enable ICAO to substantiate its work in this field; and encourages the Council to continue to cooperate closely with international organizations and other UN bodies on the understanding of aviation impacts on the environment and on the establishment of policies to address such impacts.
"White papers" containing the state of science on the environmental impacts of aviation were provided in the latest versions of the "ICAO Environmental Report", as follows:
Specifically regarding aviation impacts on Climate Change, a comprehensive assessment concerning aviation's contribution to global atmospheric problems is contained in the Special Report on Aviation and the Global Atmosphere, which was prepared at ICAO's request by the Intergovernmental Panel on Climate Change (IPCC) in collaboration with the Scientific Assessment Panel to the Montreal Protocol on Substances that Deplete the Ozone Layer and was published in 1999. The conclusions of this report include:
The new findings related to aviation emissions in IPCC AR5 are summarized in the White Paper On Climate Change Aviation Impacts On Climate: State Of The Science, published in the ICAO Environmental Report 2016.
This white paper also highlighted that the understanding and confidence in aviation climate forcings would be enhanced by a new international scientific assessment.
While a new international scientific assessment is not done, ICAO has compiled a list of supplemental references that are connected with the IPCC 1999 Report topics. This compilation is provided in the following website:
Supplemental references on the IPCC 1999 Special Report on Aviation and the Global Atmosphere.