Student Cloud Observations Help Validate NASA Satellites

Originally posted by EyeDontKnow
That article says they've observed persistent contrails for 30 years.
So that means 30 years PRIOR to the 1997 article...

edit on 28-11-2011 by EyeDontKnow because: 1997 edit

That sounds about right. I mentioned in posts in the past that I grew up near an agricultural center in the 1970s (although I lived in suburbia), and the TV had farm reports on them in the evening. That's sort of like the evening news, but with a focus on farming. I remember those farm reports would discuss the impact that long-lasting contrails -- contrails that would spread out to create a cloud-cover -- would have on farming. Farmer generally like it to be sunny, and don't like artificially-produced cloud cover.

I specifically remember this because of a boyhood fascination I had with aviation. The fact that the jet-age was helping to cause cloudy days piqued my interest.

So, yeah, persistent contrails (the kind that can become cirrus clouds) date back to at least the 1970s.

reply to post by Soylent Green Is People


Some farmers want less sun. See this 1980 report from NBC Nightly News, video available:

archives.nbclearn.com...

RICHARD SEMONIN (Illinois Institute of Natural Resources): In the absence of natural clouds, given the correct atmospheric condition, jet aircraft in high frequency can almost completely cover the atmosphere, visible atmosphere, with clouds.
O’NEIL: Semonin says, unlike most changes in the atmosphere caused by man, this one is beneficial. Clouds help farmers in the Midwest by blocking the sun. Temperature extremes can damage plants and speed up the evaporation of soil moisture. In the Winter, city people benefit because clouds act as a blanket, preventing warm air from escaping into the atmosphere. No one is trying to make clouds now using jet engines, but this study suggests that jet travel is inadvertently making our days more cloudy and some day, weather researchers may be able to use jets on purpose to change our weather. Roger O’Neil, NBC News, Champaign, Illinois.

reply to post by Uncinus


That's why I said "generally".