Can Schools Provide Ground-Truth Validation for Space-Based Earth Science?
The basic answer to this question is: “Yes, in some cases.” Using the example of aerosols, it is clear that, ideally, ground measurements should come continuously from around the globe, from a wide variety of climates. However, there are very few aerosol monitoring sites around the globe. Professional sun photometers to measure aerosol concentrations (expressed as a quantity called aerosol optical thickness) cost thousands of dollars apiece — the CIMEL sun photometers used in NASA’s AERONET network (Holben, et al., 1998) cost at least $25,000 each. These instruments rely on optical interference filters to restrict their response to a narrow range of wavelengths, but such filters are fragile and subject to unpredictable optical degradation. As a result, filter-based sun photometers are difficult to maintain and calibrate, especially in remote locations. Filter-based sun photometers are essential for research applications and they can be used in small networks, but they are impractical
