The uvbdata/ directory contains the following subdirectories:

1. requests/

This directory is for specific requests from partners.

2. cosine/, dailysums/, erythemal/, insitu/, par/.

These are the five data entities for which the UVMRP program maintains annual archives.

cosine/ – Millivolt wavelength data that has had the angular correction and nighttime bias applied.

dailysums/ – Daily/hourly integration over time. By summing the readings over the number of seconds
in the measurement period, the units of radiant power are converted to radiant energy and are useful
for studying effects related to exposure. Current available values are Caldwell biological spectral 
weighting function, Flint biological spectral weighting function, erythemally weighted irradiance, 
UV-A irradiance, UV-B irradiance, and spectral weighting function Vitamin D.

erythemal/ - The irradiance in Watts per square meter measured over the 300 through 400 nanometer 
range and weighted with the Mc Kinlay and Diffey (1987) action spectrum.

insitu/ - Calibrated UV/visible irradiance is the spectral irradiance in Watts per (square meter 
per nanometer) measured by a UV-MFRSR/VIS-MFRSR using Langley derived calibration factors that 
have been calculated using clear sky data at the deployment station. The Langley method 
extrapolates the measured direct beam to zero air mass where the incident irradiance is equal 
to the extra-terrestrial value.

par/ - Photosynthetically Active Radiation (PAR). Units are micro moles per square meter per 
second in the 400 to 700 nanometer spectral range. It is measured with a separate PAR pyranometer sensor.

Column headers common to all data entities:

ID = Site ID
UTC Date = YYYY-MM-DD HH:MI:SS (if UTC/Local unspecified, assume Local)
Local Date = YYYY-MM-DD HH:MI:SS (if UTC/Local unspecified, assume Local)
Local DOY = Day Of Year, 1-366 (if UTC/Local unspecified, assume Local)
QC = Quality Code, semi colon delimited description of known problems with data (see the 
     README in each sub-entity for codes specific to that entity)
Azi = Azimuth, degrees positive east of north
Elev = Solar Elevation, degrees
Zen = Zenith Angle, degrees
Decl = Declination, degrees
amass = Air Mass, unit less
Soldst = Solar distance, unit less

Each sub-entity also contains a README which specifies values unique to that sub-entity, 
for example unique QC codes and specifications for table column headers unique to that data sub-entity.

The sub-entity data is organized as follows:

locations/ directory
years/ directory

The locations/ directory contains a .zip file for each location. Each .zip file in locations/ 
includes all years of data. 

The years/ directory contains a .zip file for each year of data. Each .zip file in years/ 
contains data for all locations that were active that year. 

The cosine and insitu entities contain separate .zip files for UV and Visible light data. 
dailysums and erythemal contain .zip files for only UV data, and par contains .zip files for only 
Visible light data.