Contrails Map
7 comments
·December 20, 2025extropy
I'm not following the logic why contrails cause net warming.
Why nuclear blasts - that also introduce lots of particles in atmosphere cause a cooling effect - "nuclear winter"?
maltelau
Water vapour absorbs the thermal radiation (heat trying to escape earth) better than it absorbs sunlight (heat trying to enter earth). Therefore, the more water vapour in the atmosphere, the stronger the greenhouse effect.
https://en.wikipedia.org/wiki/Electromagnetic_absorption_by_...
ekunazanu
The difference is that water vapour is a greenhouse gas. IIRC the net warming effect of clouds is a function of altitude.
zeristor
Amazing visualisation, an excellent tool.
Are there other sites that can suggest how much of an issue it is, and how much flight plan tweaking could improve this.
Remember kids a 1° C rise in temperature can mean 7% more water vapour in the air, and with water vapour being a greenhouse gas itself this can cause heating and holding yet more water.
victorbjorklund
The site itself has more information. https://contrails.org/
I guess the map is posted today due to this recent video (worth a watch): https://youtu.be/QoOVqQ5sa08?si=sGK9Q9tUoFOW1QZg
dr_dshiv
Would be great for shiptracks, too— which used to mitigate 1/3 of the warming impact of maritime shipping — until the 2022 clean fuel standards were implemented.
I was expecting this to be a gag about chemtrails. I am glad I was wrong.