ICAO Adopts Intentional Contrail Cirrus Geoengineering Policy
“Contrail cirrus contributes a large fraction to the aviation induced climate impact (comparable to 50 years of aviation C02)
Satellite data analyses suggest observable impact of aviation on cirrus cover and radiation fluxes.
The climate impact of aviation induced contrail cirrus depends on aircraft properties (e.g. soot emissions) and routing (avoid cirrus forming regions) [known as Ice-Supersaturated Regions or ISSR]
Both aspect offer the potential for aviation to reduce the climate impact of aviation (less soot emissions, less warming and more cooling contrails; predictable for operational planning)” Ulrich Schumann, presentation on "Recent research results on the climate impact of contrail cirrus and mitigation options" to the ICAO Colloquium on Aviation and Climate Change.