Courtesy of Barry Lefer

From: Barry Lefer
T1, March 12, 2006

T1 Sunphotometer

Today was a bit less polluted that the past few days as winds were from the North and West. We also had the DOE G1 fly over T1 a few times, but I had left my camera in the trailer, so was not able to get any photos. This photo is of a Sunphotometer as the Sun was starting to get lower in the sky late this afternoon. This instrument has is also mounted on the roof of the UTTEC classroom building. Every fifteen minutes this sunphotometer makes a measurement of the aerosol optical depth at 8 different wavelengths (2 ultraviolet, 3 visible, and 3 infrared). Each evening, I download the data and send to NASA and a few hours later the data is reported on the NASA AERONET website: Similar Sunphotometers are also collecting data at all the other MILAGRO field sites, including: Veracruz, T0, and T2. Dr. Phil Russell is even flying a Sunphotometer on the NASA J-31 aircraft. Later on I will show some plots of the data.

Please feel free to contact me if you have any questions.

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