Ultraviolet radiation levels heading up as daylight saving arrives
26 September 2009
New Zealanders are being urged to be safe in the sun, as daylight saving arrives and ultraviolet radiation (UVR) levels
start to rise.
Wayde Beckman of SunSmart says it is important not to underestimate the power of the sun at this time of year.
“When the sun is high in the sky, UV rays have less distance to travel through the atmosphere to reach earth. When the
rays have a shorter distance to travel, less ultraviolet radiation is absorbed by gases in the atmosphere and the earth
is hit by more radiation. Spring can be deceptive, with temperatures still quite low in some places, but the sun's rays
Peak UVR periods are generally between September and April, especially between 11am and 4pm.
Ben Liley of the National Institute of Water and Atmospheric Research (NIWA) says another contributing factor to our
high UV levels is the hole in the ozone layer.
“The Antarctic ozone hole is approaching its maximum size at this time of year. Though it doesn't affect us now, when
the ozone hole breaks up we’re affected by ozone depleted air travelling over New Zealand – meaning we have to be
especially careful in the sun. The exact date of break-up of the ozone hole is not predictable, but it is usually in the
Wayde Beckman says New Zealand’s UVR levels are naturally high and it’s vital to be safe while enjoying the warm
“It’s tempting to get out in the sun at every opportunity. But we need to take care and make sure we enjoy spring while
staying safe from the sun.
“Never get sunburnt, and make sure you wear sun protective gear, such as a shirt with collar and long sleeves. Slip into
the shade, slap on a hat that protects your face, head neck and ears, slop on some 30+ SPF sunscreen, and wrap on a pair
NIWA provides daily forecasts of UVI to the media via MetService. Forecasts are also available at http://www.niwa.co.nz/services/free/uvozone