Look up in a clear blue sky on any given day and you’ll most likely see at least one vapour trail, if not many. It depends on where you are in relation to global aviation flight corridors. From satellites, they are often seen to scar up so badly it’s as if giant whips have been unleashed : The Whipped Peters of Planet Earth.
Planes don’t simply contribute to the climate emergency by direct CO2 emissions from burning fuel, although that contributes around 2.4% of all global emissions. They also create clouds, which the scientists call Contrail Cirrus RF (Radiative Forcing). Although temporary, they trap warm air below, therefore contributing to the green house effect.
Jet engine exhaust is made up of CO2, oxides of sulfur and nitrogen, soot, metal particles, water vapor, and even unburned fuel. Soot metal and other particulates already in the atmosphere provide condensation opportunities for the water vapour to form ice crystals and, therefore with the right conditions, visible trails. All we see in a blue sky with the ‘naked eye’ are the two strips of white clouds from the water vapour turning to ice after escaping from the main jet engines.
The extent to which the warming is happening is very uncertain, and not obvious in the machinations of the IPCC process.. Any albido effect is low because these manmade species* of cloud are fairly thin. The problem is an aggregate accumulation; just how many are there at any one moment on a global scale. And NASA has been warning since at least 2004.
Rates of growth of these clouds are also on the up, by the signficant increase in global flights. Yet airport expansion plans over the next decades are presented in glorious style, such as the one locally to me here in Cardiff.
Perhaps there is an immediate case to divert flights at altitude away from fire-prone zones, at least in the short term, especially in the so-called Winter season.
More: there is growing concern, plus a call for regulation, of rocket launch pollution, the effects upon the stratosphere where pollution stays for a very long time are also largely unquantified.
One day, our surviving descendents will wonder what injecting CO2 directly into the atmosphere, for the sake of human engineering prowess, war and overstated claims of liberty and adventure, must have actually looked like.
Perhaps, we should document our Whipped Peter skies to contribute towards understanding. Perhaps, @ClimateMuseumUK may be interested in such a project.
Put simply (over-simply), it is ice-crystal clear, we do not fully understand what we are doing. All life is subject to a giant experiment with no ‘scientific control’ and with no Planet B. The signs are there – look up. You’ll see the welts of a continuing enslavement of the biosphere.
Perhaps, also, a caution for the geoengineers among us ~ in the Symbiocene, there will be no direct human-made clouds. Neither will there, of course, be slavery!
*Clouds made by planes and other human activities, largely from industrial, nuclear and spacecraft and satellite launch activity, are called homogenitus clouds. They can transform over time into other species of clouds and this process is called homomutatis.
Once they appear as other clouds, they are difficult to distinguish from non-manmade cloud. And so the idea of accuracy in prediction climate models seems ever more uncertain.