It comes across as less adversarial this way. Here's a fluff piece: https://globalnews.ca/news/2934513/empty-skies-after-911-set-the-stage-for-an-unlikely-clim

It comes across as less adversarial this way. Here's a fluff piece: https://globalnews.ca/news/2934513/empty-skies-after-911-set-the-stage-for-an-unlikely-climate-change-experiment/ https://globalnews.ca/news/2934513/empty-skies-after-911-set... Something better, but need to follow references: https://www.csmonitor.com/Environment/Bright-Green/2010/0201/Airplane-contrails-and-their-effect-on-temperatures https://www.csmonitor.com/Environment/Bright-Green/2010/0201... The jury is still out on this and it seems to have a large effect and can do so in a very short time (on the order of days).