Current Status Of UV Measurements
Published 1997 · Environmental Science
The current status of UV measurements is a result of past and present perceptions of the need to know about incident solar UV radiation, and the technological ability to make the measurements. In terms of total energy the UVB part of the ground-level solar spectrum is unimportant, accounting for less than 1% of the total solar energy (the UVA accounts for a further 6–7%). However, the individual UVB photons are the most energetic to reach the surface and can initiate many biological and chemical reactions. The resulting observed effects (many of them detrimental to the irradiated system) encourage a knowledge of the causative factor (UVB) and an understanding of what governs the intensity of the irradiation. Balanced against the strength of the need to know is the ease with which the measurements can be made. In the past the perceived importance of the data has often been outweighed by the difficulty of collecting the information and UV measurements were mainly confined to short-term investigative projects. Today there are several categories of UV instnunenation available to suit different purposes. Many of the technical challenges remain but the requirement for UV data has led to a rapidly expanding number of measurement facilities and increased commitment to the task of long-term monitoring.