Could these strange blue clouds be a sign of global warming?
Blue clouds are becoming more common in certain areas, and scientists are wondering if it could be a sign of global warming. Noctilucent clouds or NLCs, which glow blue, have been appearing at more southerly latitudes, with sightings as far down as Northern California.
Computer models suggest that as greenhouses gasses warm the lower levels in the atmosphere, the upper layers cool. That scenario is conducive to these high clouds forming. Tony Phillips of SpaceWeather.com adds, "Methane drifting to the top of the atmosphere produces water, which is available for the formation of NLCs."
More possible proof was raised by a University of Colorado professor who notes that the first clouds were seen around the time of the Industrial Revolution when more gases were being produced. However, scientists remain unsure about the relationship between noctilucent clouds and global warming and believe more research needs to be done. First spotted in 1885, two years after a super volcano eruption, they can be seen in the summer months when the sky is otherwise clear.
Weird weather trends we've seen this summer:
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