Countries Obliged to Include Aviation Contrails in Climate Plans under Paris Agreement, New Legal Advice Shows - CleanTechnica

A recent legal analysis commissioned by environmental groups Transport & Environment (T&E) and Opportunity Green concludes that countries are legally obligated under the Paris Agreement to include non-CO2 emissions from aviation—such as contrails—in their national climate plans (Nationally Determined Contributions, NDCs). These non-CO2 emissions are estimated to account for at least half of aviation’s climate impact and have a significant warming effect comparable to CO2 emissions. The analysis highlights that excluding these emissions means countries are failing to meet their commitments to limit global warming to 1.5°C above pre-industrial levels, as stipulated by the Paris Agreement. The legal advice rests on three main arguments: the temperature-based targets of the Paris Agreement require addressing all warming contributors; the agreement mandates simultaneous reductions in CO2 and non-CO2 greenhouse gases; and the precautionary principle calls for action based on the best available scientific knowledge, even amid uncertainties. Aviation’s non-CO2 emissions, particularly contrails, have been