Particulate matter concentrations 2006–2013

Source:
Regional councils of Northland, Bay of Plenty, Waikato, Hawke’s Bay, Manawatu-Wanganui, Wellington, Canterbury, West Coast, Otago, Southland; district councils of Marlborough and Tasman; Nelson City Council; Auckland Council

Method:
"The annual average PM10 concentrations are from regional council and unitary authority monitoring sites. Monitoring information is only included if the site has:
- valid data for 75 percent of the year
- follows good practice approaches (Ministry for the Environment, 2009)
- has data that meets the above criteria for six of the eight years from 2006 to 2013.

The sample of monitoring sites varies year to year, with additional sites being included if best practice approaches are followed or omitted if not of adequate standard.

Trend information is only included if the site met the requirements for at least 6 out of the 8 years from 2006 to 2013. This resulted in a total of 44 sites being included for the trend analysis. Not all of these sites had data for all eight years.

Approximately 65 percent of New Zealand’s population resides within monitored areas. Some of the monitoring occurs at sites expected to have the highest concentrations (eg where home heating emissions accumulate or close to high-volume road traffic), and may therefore not be representative of the whole population of the area it is located in.



Reference:

Ministry for the Environment (2009). Good practice guide for air quality monitoring and data management. Available from www.mfe.govt.nz."