Haze-SPAN: Haze 101- Figure 11

Haze-SPAN: Haze Sun Photometer Atmospheric Network

Fig 11. AOT from 1990 until Spring 1996 as measured by Forrest M. Mims III using the first Sun Photometer to use an LED as a detector. Notice the annual cycle in AOT, with clear air occurring in the Winter and hazy skies in the Summer. The big bulge in the center of the graph was caused by the enormous aerosol cloud injected into the stratosphere by the historic eruption of Mount Pinatubo on 15 June 1991.

Aerosol optical depth at Seguin, Texas USA (29.6 N, 97.9 ); 1 Jan 90 to 2 Mar 96
Fig. 11, AOT measurement

Image: Johnny Johnson for Scientific American

TERC VHS-1 Sun Photometer: [ Figures and Illustrations Index ] [ Manual TOC ]

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