Search

In 2019, New Zealand passed “The Climate Change Response (Zero Carbon) Amendment Act” which included establishing the Climate Change Commission, a Crown entity to provide independent advice to Government to help Aotearoa transition to a climate-resilient and low emissions future. The Climate Change Commission’s first draft advice was released in January 2021 and, amongst other things, highlighted the opportunity to transition away from fossil fuels for domestic space and water heating. Compared to natural gas or LPG the use of wood burners for domestic heating, while a carbon neutral heating option, has the disadvantage of contributing to the deterioration of local air quality. In order to improve winter air quality, Environment Canterbury (ECan) has introduced a pseudo real-life wood burner authorisation test method known as Canterbury Method One (CM1). Appliances passing the CM1 test method qualify as Ultra-low Emission Burners (ULEBs) and are the only wood burning appliances allowed to be installed into houses within clean air zones in Canterbury. This paper provides updated information on the numbers and design trends of ULEBs authorised to date, and comments on how manufacturers have achieved the ULEB performance limits. The ongoing improvement of ULEBs provides the opportunity to transition away from fossil fuels toward a carbon neutral fuel without generating adverse air pollution impacts. This paper provides a summary of the journey to-date. [ABSTRACT FROM AUTHOR]

Many towns and cities around the world suffer from poor air quality in winter, a major contributor being particulate emissions from domestic solid fuel burners. New Zealand is no exception with a number of towns and cities regularly exceeding the New Zealand National Environmental Standard for Air Quality (NESAQ) for PM10 on multiple days each winter. Since the early 2000’s Environment Canterbury (ECan) has proactively taken action to improve air quality in the Canterbury region. In 2013, in order to further improve winter air quality, ECan introduced a new pseudo real-life wood burner authorisation test method known as Canterbury Method One (CM1). Appliances passing the CM1 test method qualify as Ultra-low Emitting Enclosed Burners (ULEBs) and are the only wood log burning appliances allowed to be installed into houses within clean air zones and gazetted airsheds in Canterbury. This paper discusses the steps taken and progress made by ECan in reducing the impact of particulate emissions from domestic solid fuel burners, reviews the rationale for developing ULEBs, compares the CM1 test method to the incumbent regulatory test standards, discusses how industry responded to the challenge set, and examines the design trends and the particulate emission performance of ULEBs authorised to date. Finally, the paper reviews how Canterbury’s Air Regional Plan (CARP) has enabled ULEB technology development and their impact on airsheds. [ABSTRACT FROM AUTHOR]

In Australia and New Zealand (NZ) domestic wood heater emissions contribute to a substantial community burden of air pollution-related illness and death. Despite increasingly stringent emission standards for wood heaters in Australia, there has been frustratingly little progress in reducing ambient air pollution from this source. In contrast, Environment Canterbury NZ, has made impressive progress driving innovation in wood heater designs to improve air quality. Interventions have included the 2014 introduction of a new performance testing standard, the Canterbury Method One (CM1) that is used to define a class of Ultra Low Emission Burners (ULEBs). CM1 testing is conducted under conditions intended to simulate typical home usage and includes the heater's start-up phase which generates a significant portion of pollutant emissions. It is primarily designed to test the performance of appliances burning softwoods, the main source of fuel in NZ. We aimed to: (1) design a protocol based on the CM1 for testing appliances burning Australian hardwoods, and (2) conduct preliminary evaluations of exiting ULEBs fuelled with hardwoods as a test-of-concept for ULEBs in Australia. The main variation was that we used a single burn phase with double the weight of wood compared with the standard CM1. We tested two certified ULEBs of different designs using our protocol. Emissions from hardwood fuels were higher than for softwoods as anticipated because the appliances we tested had been optimised for softwood combustion. However, the overall performance of both heaters was promising. Our results provide proof-ofconcept that ULEBs could potentially be optimised for hardwoods and have a place in strategies for reducing the harm from air pollution in Australia. [ABSTRACT FROM AUTHOR]

The significant health impacts and costs for poor indoor air quality (IAQ) are likely to be comparable if not worse than those already demonstrated for outdoor air quality. Recent assessments have placed household air pollution as the 8th largest Global Burden of Disease risk (HEI 2018) and WHO reported that "in 2012 around 7 million people died - one in eight of total global deaths - as a result of air pollution exposure. In this paper we show that these assessments while well accepted, are based a relatively small number of IAQ studies and small sample numbers. In general, there is a lack of knowledge on the sources and personal exposures to indoor air pollutants compared to outdoors. We conclude that that exposure and health risk from poor IAQ needs to be addressed similar to that of outdoor air quality. NZ and Australia need an organisation or group of organisations to take a larger responsibility or lead on IAQ. ■ To implement or coordinate monitoring programs for homes, workplaces and public buildings to determine what other issues there are and how widespread they extend. ■ To develop policies, best practice guides, indoor air quality standards and an education program for how we live in our homes/work places and public buildings to improve our collective nation's indoor air quality and our health/productivity. [ABSTRACT FROM AUTHOR]

This paper reviews recent updates in the methods available for source characterisation and dispersion modelling of emissions from flares compared to methods commonly used in Australia and New Zealand in the past. Based on two case studies representing a large refinery flare and a small landfill gas flare, the impact on the predicted downwind pollutant concentrations of using different methods to characterise the sources and to model plume dispersion has been assessed. The impact of using different modelling parameters and modelling approaches on critical plume height (CPH) calculations has also been investigated. The results of the analysis concluded that (a) plume rise statistics extracted from CALPUFF output files provide comparable predictions of CPH to those given by TAPM, and conservative estimates of plume width that potentially better reflect the effects of meteorological conditions, and (b) the Ohio 2018 and Ontario MCEP methods for characterising flare sources give similar predicted downwind pollutant concentrations and plume rise statistics, but modifying the Ohio EPA 2018 method to use source-specific values for radiative heat loss is less conservative. [ABSTRACT FROM AUTHOR]

Machine learning algorithms are used successfully in this paper to forecast reliably upcoming short-term high concentration episodes, or peaks (<60-min) of fine particulate air pollution (PM 2.5) 1 h in advance. Results are from a network around Christchurch, New Zealand, with an objective to forecast the occurrence of short-term peaks using a gradient boosted machine with a binary classifier as the response (1 = peak, 0 = no peak). Results are successful, with 80–90% accurate forecasting of whether a peak in PM 2.5 would occur within the next 60-min period. Elevated and variable nitrogen monoxide, nitrogen dioxide, and lower temperatures and wind gusts are found to be important precursors to the occurrence of PM 2.5 peaks. The use of meteorological data from a network of personal weather stations across the monitored area and from the measurement instruments was able to identify local-scale peak differences in the network. Boosted models using hourly-averaged and daily-averaged peaks as the response are developed separately to showcase differences in precursors between short-term and long-term peaks, with recent wind gusts and nitrogen oxides linked to hourly-averaged peaks and aloft air temperatures and atmospheric pressure linked to daily-averaged peaks. Results could prove useful in exposure mitigation strategies (e.g. as a short-term warning system). • High short-term (<60 min) PM2.5 concentrations were forecast, 1 h in advance. • Significant precursors were nitrogen monoxide, nitrogen dioxide, temperature and wind. • Personal weather stations helped identify local-scale processes affecting PM2.5 • Short-term results were different to daily-averaged forecasts. [ABSTRACT FROM AUTHOR]

The city of Rotorua, in the centre of the North Island, New Zealand, experiences elevated particulate concentrations during the winter months, and the ambient standard of 50 μg m-3 (24-h average) is regularly exceeded in some locations. This paper describes the ambient monitoring program, the results of a home heating survey, and the preparation of an emissions inventory for the Rotorua airshed. PM10 levels are greatest during the winter months, with levels of up to 116 μg m-3 being recorded at a 'worst-case' location. Domestic heating emissions are a significant contributor to PM10 levels, as indicated by the seasonal and diurnal variations. The home heating survey found that 50% of households used some form of solid-fuel heating, while the emissions inventory shows a more than 60% contribution, overall, from domestic heating emissions during the winter months. The key output from this work was the emission data for all source categories, based on a 250m by 250m grid across the whole of the Rotorua urban area. This was used as a primary input to a dispersion modelling study, as described in Part 2 of this paper, the results from which are being used in the development of an action plan to achieve compliance with the national standard for PM10 by 2013. [ABSTRACT FROM AUTHOR]

Abstract: Hydrogen sulphide (H2S) is one of a number of gaseous species associated with geothermal activity in the Taupo Volcanic Zone (TVZ), New Zealand. The city of Rotorua is located within Rotorua Caldera in the TVZ and is one of the few urban areas in the world where a large population (>60,000 people) is frequently exposed to geothermal emissions. In order to evaluate the health hazard from long-term exposure to H2S being emitted from the Rotorua geothermal field, a passive sampler has been developed to measure concentrations of H2S at many locations across the city simultaneously. In contrast to other passive or pump-based samplers, the sampler is inexpensive, easily mass-manufactured, and involves the reaction of H2S with silver halide contained in treated photographic paper. H2S-exposed paper shows a distinct colour change from white to dark brown as H2S concentrations increase and is sensitive to concentrations between ≪30 and around 1000 ppb. Rotorua city can be divided into three regions—an area of low H2S concentration in the west, a ‘corridor’ of high concentrations running north–south through the city centre where H2S is being emitted, and an area of medium concentration to the east which is influenced by the prevailing wind direction, creating a plume from the central corridor. The data give new insight into the subsurface routes of degassing in the Rotorua geothermal field, by showing the surface expression of the main upflow zone and the direction of the conjectured faulting below. [Copyright &y& Elsevier]

This paper concludes a series of brief papers in which we have presented and discussed the development of a new high resolution model for Australia and New Zealand. We show in this paper that the information generated by a high resolution model can be used in various ways. It can be used in its own right (e.g. emission inventory) or it can be fed into local air quality dispersion models to carry out, for example, "hot spot" analysis and impact assessment of traffic management measures. This would provide more accurate predictions than a screening model, and would be important in cases where sensitivity is required. Examples include cases where predicted air quality is close to guideline values (e.g. at critical locations such as a new residential area near a busy highway) or cases where policy measures are likely to cause relatively small impacts on emissions and fuel consumption (e.g. specific traffic management measures such as dynamic speed limits, traffic signal coordination, metering signals). [ABSTRACT FROM AUTHOR]

Abstract: Greenhouse gas emissions from international air transport were excluded from reduction targets under the Kyoto Protocol, partly because of difficulties with quantifying and apportioning such emissions. Although there has been a great deal of recent research into calculating emissions from aeroplane operations globally, publicly available emissions factors for air freight emissions are scarce. This paper presents a methodology to calculate the amount of fuel burnt and the resulting CO2 emissions from New Zealand’s internationally air freighted imports and exports in 2007. This methodology could be applied to other nations and/or regions. Using data on fuel uplift, air freight and air craft movements, and assumptions on mean passenger loadings and the mass of passengers and air freight, CO2 emissions factors of 0.82 kg CO2 per t-km and 0.69 kg CO2 per t-km for short-haul and long-haul journeys, respectively, were calculated. The total amount of fuel consumed for the international air transport of New Zealand’s imports and exports was calculated to be 0.21 Mt and 0.17 Mt respectively, with corresponding CO2 emissions of 0.67 Mt and 0.53 Mt. [Copyright &y& Elsevier]

A city is a complex system with many different components that interact to influence population health, Decisions taken in the building, energy and transport sectors all have impacts on air quality and health. Policies can have unintended consequences, including adverse health impacts and differential impacts on vulnerable populations; thus, health and social factors need to be considered from the outset in integrated policy appraisal. The shift in residential heating from solid fuels to electricity and flued gas burners reduces health problems, but unless affordable insulation and clean and affordable heating systems are installed in households, and low-income households can afford the fuel, those in poorly heated homes will suffer from excess winter illnesses. In New Zealand, excess winter mortality continues to be among the highest in the developed world. Transport system adjustments can also be evaluated in terms of co-benefits. The technological shift from petrol to diesel-driven cars may have increased the health risks from particulates, while a shift from passive car transport to active modes of transport, such as walking and cycling, would improve not only air quality but also people's physical activity: both of these are good for health. This paper reviews New Zealand research in these areas and considers the co-benefits of sector policies in relation to health and social equity outcomes. [ABSTRACT FROM AUTHOR]

Abstract: Elevated wintertime particulate concentrations in the New Zealand cities of Christchurch and Timaru are mostly attributed to the burning of wood and coal for residential heating. A carrot-and-stick approach was adopted for managing air quality in Christchurch, where strict intervention measures were introduced together with a residential heater replacement programme to encourage householders to change to cleaner forms of heating. A similar approach was only recently implemented for Timaru. This paper presents the results of a partial accountability analysis, where the impact of these measures on the target source, PM10 emissions, and PM10 concentrations are quantified. A statistical model was developed to estimate trends in the concentrations, which were tested for significance after accounting for meteorological effects, and to estimate the probability of meeting air quality targets. Results for Christchurch and Timaru are compared to illustrate the impacts of differing levels of intervention on air quality. In Christchurch, approximately 34,000 (76%) open fires and old solid fuel burners were replaced with cleaner heating technology from 2002 to 2009, and total open fires and solid fuel burner numbers decreased by 45%. Over the same time period, estimated PM10 emissions reduced by 71% and PM10 concentrations by 52% (maxima), 36% (winter mean), 26% (winter median) and 41% (meteorology-adjusted winter means). In Timaru, just 3000 (50%) open fires and old solid fuel burners were replaced from 2001 to 2008, with total open fire and solid fuel burner numbers reduced by 24%. PM10 emissions declined by 32%, with low reductions in the PM10 concentrations (maxima decreased by 7%, winter means by 11% and winter medians by 3%). These findings, supported by the results of the meteorology corrected trend analysis for Christchurch, strongly indicate that the combination of stringent intervention measures and financial incentives has led to substantial air quality improvements in the city. The lesser impact of more lenient rules and the late introduction of an incentives programme are obvious on air quality in Timaru. Trends established for the two cities were extrapolated under various scenarios to determine the likelihood of meeting air quality targets. In Christchurch the probability of compliance is low and is essentially impossible for Timaru if recent trends continue. [Copyright &y& Elsevier]

It is increasingly acknowledged that the quality of, and/or lack of, exposure data are often a weakness in studies examining links between air quality and health, In this paper we review studies of air pollution and health in Australia and New Zealand and assess the quality of exposure data used. There have been over 80 peer reviewed published studies looking at air quality and health in Australia and New Zealand. Of these, over 30 have looked overtly at health endpoints0 and more than 20 more have referred to health and/or exposure in some way. We conclude that the measures of exposure used in most of these studies are not great indicators of exposure. However, studies in this part of the world are no different to studies around the world where exposure estimates are also often weak. We suggest that as scientists we must acknowledge and accept this weakness while also agreeing that we can and must strive to develop better exposure estimates that account for intra-urban variability in pollution levels, personal mobility, and the importance of micro-environments in personal pollution exposure. [ABSTRACT FROM AUTHOR]

This paper uses observations and The Air Pollution Model (TAPM) to examine the atmospheric processes controlling air pollution dispersion for the period May 1st - August 31st 2008 in the small town of Milton, located in the southern part of New Zealand. Similar to other small towns in the region, Milton suffers from poor air quality during winter, with 43 days observed to exceed a 24-hour average PM10 concentration of 50 µgm-3 (HIGH air pollution) during the study period. Observed PM10 concentration in Milton has two air pollution peaks each day: 17:00- 1:00 NZST and 7:00 - 11:00 NZST. On HIGH air pollution days, a stable boundary layer (SBL) is typically present between 17:00 - 11:00 NZST (18 hours). The SBL reaches an average maximum depth of 150 m, with a strongly stable layer (SSL) (> 2.5 °K m-1) near the surface, which has an average depth of 25 m. Importantly, the strength and depth of the SBL and SSL in Milton is affected by the interaction of surrounding topography with gradient air flow, Modelled results compare well with observations and the performance of TAPM was found to improve using data assimilation (DA). With (without) DA, TAPM correctly predicted 58% (23%) of HIGH air pollution days. Using TAPM to assess the sensitivity of the Milton township to a range of emission scenarios suggests a 50% reduction in both industrial and domestic PM10 emissions (a total of 208 kg day-1) is required to adhere to the Air Quality National Environmental Standards (AQNES) target of one exceedance per year. [ABSTRACT FROM AUTHOR]

The Clean Heat Project (CHP) in Canterbury, New Zealand, has the objective of reducing winter air pollution and improving household energy efficiency. Through the CHP, the regional council, Environment Canterbury (ECan), assists homeowners, who use old, inefficient and polluting solid fuel home heaters, to change to low-emission forms of heating and to improve household energy efficiency by upgrading the insulation of their homes The CHP aims to convert over 26,000 homes in the city of Christchurch over an 11-year period between 2003 and 2014. Through this approach, the development of the Clean Heat brand has raised community awareness of the negative health effects of air pollution and the role the community plays in reducing air pollution from domestic solid fuel heating. Participation is on target to meet project goals for heating conversions, within budget. By mid-2009, over one-half of targeted households in Christchurch were retrofitted. Tailored CHPs have also been developed in collaboration with local communities in the smaller population centres of Timaru, Kaiapoi, Rangiora and Ashburton in 2008. The conversion rate in Christchurch and other towns will need to be increased whilst maintaining airshed capacity through voluntary conversions, or other mechanisms, in order to comply with the National environmental Standards for Air Quality by 2013. This paper discusses primarily the processes, challenges and outcomes of the Clean Heat Project; and secondly, the links to central government air quality and energy (efficiency) policy and initiatives. [ABSTRACT FROM AUTHOR]

Infrastructure systems and services (ISS) are vulnerable to changes in climate. This paper reports on a study of the impact of gradual climate changes on ISS in Hamilton City, New Zealand. This study is also the first of its kind to be applied to New Zealand ISS. In the future, the CLINZI project will extend to other areas of New Zealand. Using historical climate data and four climate change scenarios, we modelled the impact of climate change on aspects of water supply and quality, transport, energy demand, public health and air quality. Our analysis reveals that many of Hamilton City''s infrastructure systems demonstrated greater responsiveness to population changes than to gradual climate change. [Copyright &y& Elsevier]

This paper investigates seasonal patterns and annual trends of PM10 concentrations in the small town of Mosgiel located in Otago, southern New Zealand. A second aim is to explore the relationship between PM10 concentrations and concomitant meteorological factors. PM10 data were collected intermittently over a seven-year period (1998-2004) using both gravimetric Minovol and Hivol methods. Meteorological data were gathered over the same time period from two sites in the region. Although there has been an increase in annual PM10 concentrations over the period 2001-2004, the small dataset and the high variability precludes drawing firm conclusions. Monthly PM10 levels were at their highest in the winter months of June and July on days with low minimum daily temperatures, low wind speeds and little or no rainfall. the analysis shows that, based on limited data, PM10 exceeded the new national 24-hour PM10 standard of 50µg m-3 to ten times each winter. Given more frequent sampling, it is expected the number of exceedances could be significantly higher, and the Mosgiel area is unlikely to meet the new national standard, which allows only one exceedance of the standard each year. Analysis of meteorological data shows that minimum daily temperature and logarithmically transformed average daily wind-speed and total daily rainfall are all significantly correlated with PM10 concentration, but the correlations are not strong. The study highlights the need for regional authorities to undertake continuous sampling of particulate and more detailed meteorological monitoring close tot the pollution sources in order to better understand the air pollution meteorology of this small town. [ABSTRACT FROM AUTHOR]

This paper describes experience of a strategic-level social impact assessment (SIA) carried out in New Zealand to assist policy decision makers in a regional government environmental agency. The phased, iterative approach to the SIA is discussed, as well as the significance of effective scoping early in the SIA process. The SIA linked air pollution, cold homes and poor health problems as inseparable components of a single public policy issue, and thereby helped lay the foundations for political consensus, more cooperative implementation and greater public acceptance. Details of a proactive approach to mitigation are also provided. [ABSTRACT FROM AUTHOR]

Outlines one of the papers presented in the National Indoor workshop sponsored by The Clean Air Society of Australia and New Zealand on August 19, 2002 at the Christchurch Convention Centre, New Zealand. Workshop presentation; Provision of some background on bioaerosol research; Definition of terms associated with bioaerosols in the indoor environment.

The composition and relative abundance of airborne pollen in urban areas of Australia and New Zealand are strongly influenced by geographical location, climate and land use. There is mounting evidence that the diversity and quality of airborne pollen is substantially modified by climate change and land-use yet there are insufficient data to project the future nature of these changes. Our study highlights the need for long-term aerobiological monitoring in Australian and New Zealand urban areas in a systematic, standardised, and sustained way, and provides a framework for targeting the most clinically significant taxa in terms of abundance, allergenic effects and public health burden. [ABSTRACT FROM AUTHOR]

The article relates the author's expectations on the 20th Clean Air Society of Australia and New Zealand (CASANZ) Conference to be held in Auckland, New Zealand in 2011. As CASANZ president, the author expects interesting presentations by speakers and papers with the theme "Air Quality: A Healthy Balance." He says that keynote speakers should provide international flavour to the event. He also explains the importance of networking in the event, which can lead to future joint projects.

Highlights the 8th International Global Atmospheric Chemistry Conference in Christchurch, New Zealand, on September 4-9, 2004. Role of conference convener Dave Lowe in the success of the conference; Number of scientific papers presented; Keynote speakers; Emphasis of the conference on the influence of megacities on atmospheric composition and air quality.

Emissions trading schemes for the regulation of GHG emissions have captured much attention in the United States and in many other countries. New Zealand's national scheme is arguably the most ambitious in the world to date. It takes a pioneering approach to coverage, linkage into the international markets, allocation of emissions units, and speed of implementation. In a world-first, it covers both the agriculture and forestry sectors. This Article describes the New Zealand scheme in its context and analyzes its advantages and pitfalls. It also investigates the broader implications of the New Zealand example as a model for climate change regulation elsewhere. [ABSTRACT FROM AUTHOR]

Worldwide, the increasing deterioration in urban air quality due to vehicle emissions has created the need for greater capacity in air quality management and more comprehensive knowledge about the sources and spatial and temporal distribution of vehicle emissions, without which impact studies and subsequent mitigation policy cannot be formulated. To investigate this proposition and assist with the design/development of new air quality information tools for this evolving context, this research examines the generation and use of air quality information in New Zealand, through two case studies. The first case study examines NZTER, a tool used for generating 'vehicle fleet emission rates information' used in a number of different models for air quality assessment and transport policy. The second case examines the early stages of the development and operationalisation of an integrated environmental management tool, the VFEM-w, which hopes to quantify/model the type, source and pathways of airborne pollutants entering the urban stormwater water system. While the NZTER is uncomplicated, it is inefficient and produces information of insufficient quality in the current policy-making context. The VFEM-w case illustrates the challenges of attempting to embed a conceptually and technically complex model in an existing cultural, technical and political setting. Recommendations for the use and development of air quality information tools are made and closing comments consider the issue of information quality in sustainable management. [ABSTRACT FROM AUTHOR]

A study has been performed on the characteristics and behavior of surface ozone concentrations at four monitoring sites in Auckland, New Zealand (37°S, 174.8°E) for a four-year period (October 1997–October 2001). One monitoring site (rural) was located upwind of the Auckland urban complex, a second downwind (rural-coastal), and a third within the urban area, while the fourth was an elevated urban-city site located 250 m up the Sky Tower in the central city. In contrast to the high elevation site, the diurnal behaviour of ozone at the three low elevation sites followed a typical solar radiation cycle with high ozone during the day and low nocturnal values. The effect of NOx titration was distinct at the urban sites. There was also a seasonal variability in the measured ozone levels with high concentrations in spring and a significant summer minimum. The observed surface ozone concentrations in Auckland were significantly lower than other cities of the world, although a potential for high oxidant formation existed. Observed ozone episodes appear to have been either generated locally or the precursors transported via the prevailing southwest wind. A unique feature of Auckland's air quality is the dilution of polluted city air due to the mixing of east-coast air into the clean west-coast circulation leading to the overall lower average concentrations in summer. A second feature is the potential interaction between sea salt particles and ozone that may provide an additional ozone loss mechanism. [ABSTRACT FROM AUTHOR]

The article offers branch updates regarding air quality which include the New Zealand branch meeting which tackles on air particulate matter research project, the National Clean Air Agreement Forum hosted by New South Wales, and a joint seminar on radionuclide dispersion in New Territory.

An introduction is presented in which the editor discusses various reports within the issue on topics including history of air quality in Australia and New Zealand, air quality science, and ongoing discussion surrounding National Clean Air Agreement for Australia.