UV Index graph
During the day ultraviolet radiation increases to a peak and these measurements are graphed daily. The actual peak level reached depends on factors such as the ozone levels, cloud cover, water vapour and other particulate matter in the atmosphere.
The blue line represents actual readings taken by ARPANSA dataloggers and the red line reflects the predicted UV for a clear day. Such graphs help us to understand when the peak UV occurs, as well as appreciate that in our Queensland summer the UV remains over 3 for a large part of the day, during which we should be mindful of appropriate protection if outdoors. In Brisbane during the winter months the intensity of the UV is less but it is still important to be Sunsmart when the UV is over 3.
In contrast the Cancer Council of Victoria recommend the first of May means "hats off day" for Victorians to ensure people get enough sun exposure for vitamin D production in their skin in the Victorian winter. This is due to the fact that in the Southern state the UV is less intense in their winter and may not reach over an index of 3.