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Air pollution and New Zealand's air

This page outlines what air pollution is and has information on air quality in New Zealand.

About air pollution

Many of our daily activities release chemicals and particles into the air we breathe. Those that have the potential to affect our health and the environment are called contaminants or pollutants.

The concentration of air pollution in our environment depends on both the amount of pollution produced and the rate at which pollutants disperse. This depends largely on wind (both strength and direction). In areas where the wind is very strong, pollution is dispersed and blown away. In areas where there is little or no wind, air pollution accumulates and concentrations can be high.

Air quality in New Zealand

New Zealand has relatively good air quality due to our low population density, close proximity to the sea and remoteness from other continents and sources of pollution. However there are some places in New Zealand, especially in towns and cities where air pollution does affect our health and the enjoyment of our environment.

These are usually places where homes are heated mainly by solid fuel (eg, wood or coal) or with high volumes of traffic. Air pollution is more likely to occur when there is little wind. Topography (hills and mountains), proximity to the coast, building height and time of the year all affect local wind conditions and can affect air pollution levels.

In winter, inversion layers can develop on still evenings and mornings. These trap pollutants near the ground and concentrations can build up to levels that affect your health. As the sun warms the air, inversion layers usually break down enabling pollutants to disperse. However, inversion layers can remain for two or three days. They develop frequently in some South Island towns and cities during winter.