Atmosphere

A glossary of common climate change and meteorological terms.

The UV Index is a measure of the intensity of UV radiation. The larger the number, the more intense the UV. In New Zealand, its maximum summer value is generally about 12, but it can exceed 13 in the far North. In winter it reaches peak values of 1 or 2. Values of 10 or more should be considered as "extreme". At high altitude tropical sites (eg Mauna Loa Observatory, Hawaii), the UV Index can exceed 20.The UV Index supersedes the idea of "Time to Burn" or "Burn Time", which has been used previously in New Zealand.

Several apps that provide forecasts of the UV index (UVI) are available for smartphones. 

Information about climate and weather and links to climate-related websites.

Plots of UV levels throughout the day at different locations.

NIWA provides ambient air quality monitoring services using low-cost ODIN (Outdoor Dust Information Node) sensors.

Descriptions of the common terms that explain the processes that occur in hydrology.

NIWA has developed personal UV dosimeter badges to support studies relating UV exposure to human health.

Antarctica is experiencing stunning skyscapes like those recently seen in New Zealand, thanks to the afterglow effect from the Tongan volcano.

The atmosphere is comprised of layers based on temperature. These layers are the troposphere, stratosphere, mesosphere and thermosphere.

More information about NIWA's UV Atlas

Common questions about storms and cyclones in New Zealand.