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ENASA satellite finds Earth’s clouds are getting lower
(PhysOrg.com) — Earth’s clouds got a little lower — about one percent on average — during the first decade of this century, finds a new NASA-funded university study based on NASA satellite data. The results have potential implications for future global climate.

Scientists at the University of Auckland in New Zealand analyzed the first 10 years of global cloud-top height measurements (from March 2000 to February 2010) from the Multi-angle Imaging SpectroRadiometer (MISR) instrument on NASA’s Terra spacecraft. The study, published recently in the journal Geophysical Research Letters, revealed an overall trend of decreasing cloud height. Global average cloud height declined by around one percent over the decade, or by around 100 to 130 feet (30 to 40 meters). Most of the reduction was due to Read more…
Mysterious Night-Shining Clouds Getting Brighter
Clouds bright enough to see at night are not as hard to find as they once were.
These so-called night-shining clouds are still rare — rare enough that Matthew DeLand, who has been studying them for 11 years, has seen them only once. But his odds are increasing. [Related: In Images: Reading the Clouds.]
These mysterious clouds form between 50 and 53 miles (80 and 85 kilometers) up in the atmosphere, altitudes so high that they reflect light long after the sun has dropped below the horizon.
DeLand, an atmospheric scientist with NASA’s Goddard Space Flight Center in Greenbelt, Md., has found that night-shining clouds — technically known as polar mesospheric or noctilucent clouds — are forming more frequently and becoming brighter. He has been observing the clouds in data from instruments that have been flown on satellites since 1978.
For reasons not fully understood, the clouds’ Read more…