The International Air Transport Association (IATA) urged that urgent measures be taken to deepen the knowledge of the formation and climate impact of aviation contrails, in order to develop effective mitigation measures.
According to its report Aviation Contrails and their Climate Effect: Tackling Uncertainties and Enabling Solutions, the agency urged intensified collaboration between research and technological innovation , in combination with policies addressing non-CO2 aviation emissions and increased collection of atmospheric data.
The report highlights the complexity of the nature of contrails and points out gaps in the understanding of their formation, persistence and impact on the climate.
He stated that the lack of high-resolution, real-time data on atmospheric conditions, particularly humidity and temperature at cruising altitude, makes it difficult to accurately forecast contrails.
“Industry and stakeholders are working together to address the impact of non-CO2 emissions on climate change, particularly the impact of contrails. To ensure this effort is effective and has no adverse effects, we must better understand how and where contrails form and reduce uncertainty about their impacts on the climate,” he said. Willie Walshdirector general of IATA.
He added that “Acting now” means conducting more tests, collecting more data, improving climate models and perfecting technology and operations. Formulating and implementing regulations based on insufficient data and limited scientific knowledge is foolish and could have adverse effects on the climate.
“We hope that this report will raise awareness among all stakeholders of the need to join forces to address current gaps in science so that we can take effective action,” Walsh said.
Based on current knowledge, IATA made the following short-term recommendations (2024-2030): The priority should be to reduce CO2 emissions by increasing airline participation in screening programs, as well as advancing research scientific research and the improvement of climate and humidity models.
In the medium term (2030-2040) the agency indicated that they should include the creation of a regulatory framework for the transmission of data, the continuous validation of models, and encouraging aircraft manufacturers to include provisions for meteorological observations, as well as the possibility of avoiding condensation trails.
Finally, in the long term (2040-2050) he indicated that actions should focus on the continuous transmission of data from aircraft and the use of reliable models and infrastructure. The community will then have a more complete understanding of the non-CO2 effects of alternative fuels, accompanied by broader mitigation measures.
Together, the measures aim to mitigate the climate impact of aviation, while advancing scientific knowledge and technological capabilities, according to A21.
He explained that the impact of aviation on the climate goes beyond CO2 emissions, such as contrails and nitrogen oxides (NOx), which also contribute to global warming.
Persistent contrails, which form in moisture-saturated regions, transform into cirrus clouds that reflect incoming solar radiation (during the day) and retain outgoing heat. Contrails are therefore considered to have a climate warming effect, with diurnal, seasonal and geographical variations.
However, despite extensive studies, there are still significant uncertainties in the ability to predict individual contrail formation and its specific impacts on climate.
The most recent results, the result of collaboration between meteorologists, climate researchers, airlines and aircraft manufacturers, underline the need to improve data collection and analyze the possible consequences for the global air traffic network of the measures to be adopted.
Tests using modified Flight paths and alternative fuels have demonstrated potential, although limited, effectiveness due to the variability of atmospheric conditions and the nature of contrail locations.
Advances in the development of humidity sensors for aircraft are critical to contrail prediction and avoidance strategies.
Current technology in commercial aircraft lacks the necessary sensitivity and response time, apart from the scarcity of such sensors currently operating at the required altitude.
“Ongoing research aims to develop more accurate, reliable and large-scale solutions, and the use of sensors on a limited series of aircraft would allow mathematical weather prediction models to be improved and validated,” the agency notes.
It was added that it will be the topic of debate at the next Annual General Assembly of the Association, which will be held in Dubai, from June 2 to 4.