Daily sum values represent an integration over time. Basically 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 daily effects related to daily 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 Vitamin D. Similarly, it is also possible to view the sums of biologically weighted indices over monthly or annual periods from selections on this page.


Graphs of the data are available for a time selection of a year or less. The graphs will be displayed along with a tabular view of the data used to create the graphs. We also provide a feature to export the data to a file on your local computer in a comman delimited(CSV) format.


For any time duration greater than a year, use the end date option below. This will generate a data file that you can download to your local computer.