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A comment on LA is dumping millions of plastic balls into its reservoir to tackle the drought. Parent comment

Re:LA is dumping millions of plastic balls into its reservoi... by StavrosK on Thursday August 13, 2015 @04:57AM (#10052905)
They don't care that much about heat, they care more about sunlight not reaching the water, which black balls are more effective at.
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Re:LA is dumping millions of plastic balls into its reservoi... by markyc on Thursday August 13, 2015 @07:27AM (#10053388)
why would black be better than white?

i remember an article stating that the melting ice at the poles is accelerating global warming because the white of the ice used to reflect the light coming towards the water

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Re:LA is dumping millions of plastic balls into its reservoi... by rsfern on Thursday August 13, 2015 @08:53AM (#10053736)
The problem is specifically the ultraviolet photons in the sunlight, which photoactivate the reaction between bromine ions and ozone to form bromate [1].

The visible color shouldn't matter as much as strong absorbance or reflectance in the UV band. I would guess that they're using a plastic that absorbs UV, or contains a dye that does so.

1: http://www.ncbi.nlm.nih.gov/pubmed/18290477

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Re:LA is dumping millions of plastic balls into its reservoi... by StavrosK on Thursday August 13, 2015 @08:01AM (#10053493)
Because white reflects, black absorbs. White balls wouldn't reflect all light upwards. To put it another way, if you were in the water, looking at the surface, which would be brighter? White balls or black balls?
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Re:LA is dumping millions of plastic balls into its reservoi... by markyc on Thursday August 13, 2015 @08:46AM (#10053693)
makes sense :)
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