Why is the UV index so low when the sun is still high on a very hot day?

Question

For example in Perth, WA today the UV was only “1 – Low” at 6pm, when the sun was still quite high in the sky. The temperature was still 34 degrees and you could really feel the sun’s heat.

How could you be at such low risk of sunburn under those conditions?

In: Planetary Science

Answer 1

If you’re at a high latitude, the sun’s rays have to go through more atmosphere. That filters out UV. In the winterish part of the year, even at noon, you’re not going to be getting sunburn or generating Vitamin D.