Air quality data
One of the main air pollutants in Canterbury is airborne particles, often referred to as particulate matter (PM). These particles are defined by their size, with particles smaller than 10 micrometres referred to as PM10 and those smaller than 2.5 micrometres as PM2.5. It is important to know that PM10 includes all the PM2.5 particles and larger particles up to 10 micrometres in size.
We monitor PM2.5 and PM10 concentrations in our region's eight airsheds. This allows us to compare concentrations with national standards, assess variations over time and understand local variations such as weather. View the latest air quality science snapshot report (PDF file, 3.73MB).
Real-time air quality monitoring data
The table below shows the daily average PM10 and PM2.5 concentrations measured yesterday. Also shown are the number of high air pollution events so far this calendar year (table and map). That is the number of days when the average PM10 concentrations were greater than 50 micrograms per cubic metre of air (µg/m3) and when average PM2.5 concentrations were greater than 25 µg/m3.
Click on a town to see hourly concentrations from yesterday and today, daily average concentrations this year and the number of high air pollution events so far this calendar year, i.e. when pollution levels exceeded national standards and regional targets. Where there are multiple sites in an airshed, like Christchurch, one event is recorded for the airshed if concentrations at any or all sites exceed standards/targets on one date.
This data has undergone preliminary checks only and may change after further validation.
How our PM monitoring system works
We use a modern air quality monitoring system called Fidas to measure PM in the air, including PM10 and PM2.5. This system uses laser technology to detect the PM by measuring how light scatters as it passes through the monitor.
Measurements are taken every minute or less. This provides fast, reliable data that shows how air quality changes throughout the day and night, including during short-term pollution events and over longer periods.
For reporting and assessment purposes, hourly PM concentrations are averaged into a daily concentration, measured from midnight to midnight. This approach aligns with national air quality standards and allows results to be compared consistently across sites and over time.
Daily concentrations are used to assess air quality in Canterbury’s airsheds and to track progress against targets set under the National Environmental Standards for Air Quality.
Meeting the National Environmental Standards for Air Quality
The Canterbury Air Regional Plan will help us to meet national air quality standards. The plan sets out how we are going to manage air pollution from home heating, industry, and other sources like outdoor burning, dust and odour. It has a 2030 target for no daily average PM2.5 concentrations greater than 25 micrograms per cubic metre of air. PM2.5 is used in the plan as the PM10 exceedances in most Canterbury airsheds are largely due to PM2.5 from home heating.
Additional monitoring data
We have also measured gaseous pollutants, such as carbon monoxide, sulphur dioxide and nitrogen dioxide which do not exceed the National Environmental Standards for Air Quality. You can find this data on the Land Air Water Aotearoa (LAWA) website.
For daily and hourly concentrations, visit our Open Data Portal.