| Cloud changes may lower global temperature |
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22/02/2012 05:58 (89 Day 06:50 minutes ago) | |||||
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The FINANCIAL -- Research from The University of Auckland on changes in cloud height in the decade to 2010 has provided the first hint of a cooling mechanism that may be in play in the Earth’s climate.
According to The University of Auckland, published in the journal Geophysical Research Letters, the analysis of the first ten years of data from the NASA Terra satellite revealed an overall trend of decreasing cloud height. Global average cloud height declined by around 1 per cent over the decade, or around 30 to 40 metres. Most of the reduction was due to fewer clouds occurring at very high altitudes.
A consistent reduction in cloud height would allow the Earth to cool to space more efficiently, reducing the surface temperature of the planet and potentially slowing the effects of global warming. This may represent a “negative feedback” mechanism – a change caused by global warming that works to counteract it.
University of Auckland physicists Professor Davies and Matthew Molloy, a BSc Honours student, analysed measurements of the Multiangle Imaging SpectroRadiometer, one of the instruments on the Terra satellite launched by NASA in December 1999. The instrument uses 9 cameras at different angles to produce a stereo image of clouds around the globe, allowing measurement of their altitude and movement.
Professor Davies holds the Buckley Glavish Chair in Climate Physics at The University of Auckland. The current research was funded by NASA’s Jet Propulsion Laboratory, which is managed for NASA by the California Institute of Technology.
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