Largest network of ground-based sensors monitor aerosols

Flight Center in Greenbelt, Maryland were attempting to study vegetation using satellites. They encountered considerable difficulty, as satellites could not properly sense the vegetation through all the dust, minerals, soot, salt, and other atmospheric aerosols.

This prompted the researchers, including current manager of AERONET Brent Holben, to put aside vegetation research to tackle aerosols.

In 1992, Holben planned a field campaign to the Amazon, where farmers were burning swaths of rainforest to clear the land. The heavy emissions from the fires made it an ideal environment to study aerosol particles. It was there that Holben began to develop a method for studying aerosols that became a template for future campaigns.

The method uses lamp-sized instruments called sun-sky photometers to measure the intensity of light filtering through a given column of atmosphere. Aerosol particles scatter or absorb portions of incoming light, allowing scientists to deduce their size, shape, and chemical composition.

Holben and his collaborators realized that they had created a global network. In 1998, he described the network’s potential in an article in Remote Sensing of Environment, laying out methods of calibrating the sensors and guidelines for collecting and interpreting data. With that paper, AERONET was officially born. Today, AERONET consists of approximately 400 sites in 50 countries on all seven continents.