Why is the risk of skin cancer so high in New Zealand?

If you talk to those who travel, it is widely noted that the intensity of the sun in New Zealand is significantly higher than that in North America or Europe. In fact, a NIWA study has shown that our UV index is approximately 40% higher than similar latitudes in the northern hemisphere.

It is interesting to note in the recent publication of the NZ Health Promotion Agency (New Zealand Skin Cancer Primary Prevention and Early Detection Strategy 2017 to 2022) the following three reasons are listed as the main causes of the difference in UV index intensity:

1. Our clearer, unpolluted skies (a 20% effect)
2. Our lower ozone levels (a 7-10% effect)
3. The reduced distance between us and the sun during our summer compared to a northern hemisphere summer due to the elliptical orbit of the earth around the sun (a 7% effect)

The full document can be read at