Photosynthetically Active Radiation (PAR) irradiance in Watts per square meter measured over the 400 through 700 nanometer range and is measured with a separate PAR pyranometer sensor. For more information about this instrument please see Instrumentation.
The data is downloaded in CSV format. Each set of data has a header. The header lines begin wth the # sign, and contains a description of location and data, along with possible data issues. The nighttime data is set to -9999 and data that are not currently available or associated with instrument errors are set to -9998.