What is UV radiation?
The sun sends out different types of radiation – visible light that we see as sunlight, infrared radiation felt as heat and UV radiation that we can't see or feel.
People often confuse infrared and UV radiation. When the temperature is cool it means less infrared radiation but not necessarily less UV radiation.
Types of UV radiation
There are three types of UV radiation, categorised by wavelength: UVA, UVB and UVC.
- UVA can cause sunburn, DNA (cell) damage in the skin and skin cancer.
- UVB causes skin damage and skin cancer. Ozone stops most UVB from reaching the earth's surface.
- UVC is the most dangerous type of UV. Ozone in the atmosphere absorbs all UVC so none reaches the earth's surface.
Factors affecting levels of UV radiation
Levels of ultraviolet (UV) radiation from the sun change throughout the day, every day, each month, each season, each year, across Australia.
The total amount of UV radiation present at a given location is affected by:
- closeness to the equator
- time of day
- time of year
- cloud cover
- altitude
- scattering
- reflection.
Also refer to:
- FAQs about UV radiation
- World Health Organization, Intersun Programme for frequently asked questions relating to UV radiation
- Australian Radiation and Nuclear Protection Agency for more information about measuring and forecasting UV radiation
