The Ministry for the Environment and StatsNZ released Our Air 2024, an update on the state of the air in Aotearoa/New Zealand’s. This is a very important document, and we can’t pass the opportunity to give our perspective on its content and what it may mean for air quality management in our country.
Given Aotearoa New Zealand’s geographical isolation in a windy zone of the south Pacific, we should have some of the best quality air in the world. Whereas NZ is a well-monitored country by international standards, the Our Aur 2024 report recognizes that this monitoring is biased towards our more polluted locations and thereby forms an incomplete picture. Not only are our less urbanized areas not monitored, even some major and growing cities, like Palmerston North and Queenstown, have no regulatory-standard air quality monitoring.
Monitoring is getting cheaper, potentially enabling more organisations to get involved, presenting a major opportunity for the future to improve our understanding of air quality and options to improve it.
Whereas this report does not make direct international comparisons, it does clearly show that many of our more polluted locations fail to meet World Health Organisation guidelines, even 20 years after the adoption of National Air Quality Standards for Air Quality and a legal framework to meet them.
The more polluted locations tend to be in South Island and inner North Island, due mainly to winter home heating emissions from solid fuel fires, and in city centres and near major roads across the country, but especially Auckland. New Zealand’s naturally clean air continues to be compromised by a relatively old (mostly second-hand) and polluting vehicle fleet, and an outdated and polluting form of home heating.
Although air quality is improving at more sites than it isn’t, the rate of improvement is very slow and will take decades to meet WHO guidelines at the current rate in many places. During this time the health impacts reported in Our Air are accumulating every year.
The report indicates that air quality is improving in many more places and by more measures than instances where it is steady or worsening. There are successes worth celebrating, mainly driven by transition from soild fuel (home heating) and fossil fuels (transport) to electricity. Furthermore, reductions in sulphur dioxide from reduced use of coal and international regulation of shipping are significant and likely to be permanent.
The report does note, however, that future trajectories are quite sensitive to the rate at which transitions to electricity continue, which are subject to unpredictable market forces, but also policy settings and incentives.
There has been a dramatic reduction in nitrogen dioxide (from traffic) levels in Auckland’s Queen Street, which is included in one of the report’s figures (5), but not mentioned in the text. This is due to the substantial reduction in traffic along this important street where large numbers of people are exposed. Relatively simple policy measures have led to small changes in traffic flow with a large health impact in part due to New Zealand’s windiness and very clean background air, meaning the gains in clean air are not nullified by polluted air blowing in from elsewhere.
We are glad to see the report acknowledge what the science research community have known for decades – that there is no safe and healthy level of air pollution, even if National Environmental Standards are met. This means health benefits can be achieved by reducing air pollution regardless of what the current levels are.
