January 1, 2010.
The sun photometer data was collected and organized by the Aerosol Robotic Network (AERONET) program at NASA GSFC. These sun photometers measure AOD by looking at the sun using 8 different filters that take measurements at various wavelengths. The larger the AOD at a particular wavelength means that less of that wavelength is being transmitted to the Earth's surface. An optical depth 1 or greater indicates a hazy sky condition while an optical depth of less than 0.1 indicates clear skies. This summer I decided to research whether elevation had any affect on the AOD value. I chose locations across the United States and others around the globe. In order to limit the amount of variables involved, I compared the AOD at locations along the East Coast, Midwest, and West Coast of the US. These locations also had a range of elevations.
NASA Goddard Space Flight Center (GSFC)