جودة الهواء في Tasmania

How bad is the air quality in Tasmania?

Tasmania, the island state located 240 km south of the Australian mainland separated by the Bass Strait, experiences some of the cleanest air quality in the world, year-round. However, like the rest of Australia, Tasmania air quality is also subject to occasional short-term extreme pollution events, such as smoke from bushfires and dust storms. Particulate matter is the main pollutant of concern in Tasmania. Particulate matter describes tiny airborne particles, measuring 2.5 or 10 microns in diameter or less (abbreviated as PM2.5 or PM10), and these particles are particularly hazardous to human health since their microscopic size enables them to travel deep into the human system, even the bloodstream, in the case of PM2.5. While Tasmanian levels of PM are generally low in global comparison, they do experience occasional spikes due to wood heaters, bushfires and landscape burning.

Live air quality information can be viewed in the Tasmania air quality map at the top of this page, which includes real-time wildfire updates. This information can also be viewed any time using the IQAir AirVisual air quality app, along with a 7-day Tasmania air quality forecast.

Does Tasmania have the cleanest air?

In general, Tasmania has the cleanest air quality in Australia. According to IQAir’s 2019 World Air Quality Report, 23 out of the 24 Australian locations with the lowest levels of airborne PM2.5 pollution were located in Tasmania.¹ At the global scale, Tasmania also has some of the world’s cleanest air quality for PM2.5 levels: the Tasmanian locations of St Helens and Emu River ranked as the world’s 4th and 5th cleanest locations for PM2.5 concentrations, globally (averaging an annual measure of 2.4 μg/m³ and 2.5 μg/m³ respectively). These were beaten only by 3 locations within a rival island state, Hawaii, whose Kailua-Kona and Captain Cook locations ranked jointly as the world’s cleanest places for PM2.5 (1.9 μg/m³ each), followed by Waimea (annual average of 2 μg/m³). The capital, Hobart’s air quality, meanwhile ranked as Tasmania’s 25th most polluted city out of 35 locations, with an annual average PM2.5 level of 4.4 μg/m³.

However, it is also worth noting that some locations within Tasmania exceeded Australia’s national annual air quality standard for PM2.5 pollution, which is set at an annual mean concentration of 8 μg/m³. This included 6 out of 35 locations included in IQAir’s 2019 World Air Quality Report, with the most polluted as the small town Geeveston’s air quality (11.8 μg/m³), followed by Longford (9.5 μg/m³) and Hadspen (9.3 μg/m³).

A special monitoring station located on the Cape Grim peninsula at Tasmania’s northwestern tip, has garnered a reputation for Tasmania having the cleanest air quality in the world. The Cape Grim Baseline Air Pollution Station has been installed there since 1976, deliberately located at a spot far away from human-influenced pollution sources: the nearest landmass to the west is Argentina, and to the south, Antarctica. The measurements taken at Cape Grim are intended to act as a baseline, to show how polluted the cleanest air in the world can be, as global pollution levels rise. In addition to air pollutants causing human health hazard, such as particulates, the station has also measured carbon dioxide levels over time, registering an alarming rise. Since the station was established in 1976, its background carbon dioxide levels have risen from 330 parts per million (ppm), up to 405 ppm, reflecting the higher levels of CO₂ in the atmosphere, contributing to global heating and climate change.²

Where is the best air quality in Australia?

While Tasmanian locations ranked as the cleanest in terms of PM2.5 air quality overall in IQAir’s 2019 World Air Quality Report, the town of St Helens’ air quality ranked as the cleanest of all, with an annual average PM2.5 concentration of 2.4 μg/m³. Following were Emu River (2.5 μg/m³), and the towns of Fingal (3 μg/m³) and Derby (3.4 μg/m³).

What are the health effects of Tasmania air pollution?

Exposure to air pollution can aggravate existing respiratory conditions such as asthma, and cause short-term effects such as the irritation of eyes, nose and throat. Long-term effects of exposure to air pollution can furthermore increase the risk of developing cardiovascular and respiratory disease, such as chronic obstructive pulmonary disease (COPD) and lung cancer, and ultimately increase chances of premature mortality and death.

Although Tasmania has relatively low levels of ambient air pollution in comparison to global locations, it’s important to emphasise that air pollution can cause health effects at even low levels. The World Health Organisation (WHO) emphasises that there is no known “safe” limit below which no health impacts from exposure to particulate matter pollution can be observed. Accordingly, despite Tasmania’s comparatively low levels of PM2.5 pollution, researchers have estimated the health impacts from air pollution stemming from landscape burning and wood heater smoke in Tasmania, to result in 69 premature deaths, 86 additional hospital admissions, and 15 asthma ED visits annually, with 74% of these impacts attributed to wood heater smoke alone.³

What are the main sources of Tasmania air pollution?

Tasmania’s main air pollution sources vary by season. Its levels of fine particulate matter (PM2.5) vary significantly by season due to wood heating during winter, planned forest fires during autumn and spring, and wild bushfires during summer months.³

During winter months, wood heaters are the main source of smoke in Tasmania, negatively influencing air quality in many areas. Poorly operated wood heaters not only create heat less efficiently, but also produce more smoke. Tasmania’s Department of Health recommends these steps to reduce smoke from wood heaters:⁴

• Use dry firewood, and store firewood under cover
• Use smaller rather than larger logs
• Keep the flue open for at least 20 minutes after starting the fire or adding wood
• Regularly maintain the heater’s flue

Does Tasmania have wildfires?

Australia as a whole has long experienced wildfires during its hotter months, with an established “fire season”. Fires are most often started naturally, through a lightning strike, although they can also be stared by human intervention: either by accident, such as via an accidental spark, or deliberately, through planned burning or arson. However, during the 2019-2020 summer, known colloquially as the “black summer”, Australia experienced some of the most devastating wildfires on record. This was due to several months of drought, low rainfall, and record-breaking temperatures. While separated by sea from the Australian mainland, Tasmania was no exception to the black summer’s wildfires.

Exceptionally hot and dry conditions led to the eastern half of Tasmania recording its highest ever December Forest Fire Danger Index (FFDI) on 30 December 2019, with several Tasmanian locations recording temperatures across the high 30’s and low 40’s (degrees Celsius). That day, the state recorded 406 lightning strikes which ignited dozens of bushfires on that day. One notable fire began in the Upper Derwent Valley, 45 km north-west of the Tasmanian capital Hobart, then spreading southeast to rural communities in Elderlie and Broadmarsh. The fires grew and blazed until 11 January 2020, while a separate group of fires burned generating smoke around Fingal during this same time. Eventually, the 2019-2020 black summer fires had destroyed 36,000 hectares of land across Tasmania, including 22,000 hectares of plantation, with an estimated value of $70 million AUD (equivalent to approximately $52 million USD).⁵

While Australian wildfires have devastating direct consequences in terms of burned land and human casualties from fire, the indirect health impacts from Australia bushfire smoke are estimated to be even worse. While the black summer’s bushfires reportedly led to the deaths of 33 people from fire, experts estimate that health impacts from inhaling the fires’ smoke led to 417 premature deaths, 3,151 additional hospitalisations for cardiorespiratory problems, and 1,305 extra hospital attendances for asthma attacks.⁶

What is Tasmania doing about air pollution?

Tasmania’s Environment Protection Authority (EPA) runs a statewide air quality monitoring network, called the Base Line Air Network of EPA Tasmania (abbreviated as BLANkET). The network’s monitoring stations focus on measuring particle pollution, both PM2.5 and PM10, which comes mostly from smoke and dust. In communicating this data to the public, rather than using a Tasmania Air Quality Index, or Tasmania AQI, following Australia’s broader air quality index system, Tasmania EPA uses a system of ‘air quality categories’ to convey the health impacts of pollution levels. The Tasmania air quality categories are based on hour-averaged values of PM2.5, with 0-10 μg/m³ representing “Good” air quality (matching the WHO’s annual PM2.5 standard); 10-25 μg/m³ representing “Fair” air quality, 25-100 μg/m³ representing “Poor”, and over 100 μg/m³ representing “Very poor”.⁷ In addition to monitoring PM pollution, monitoring of other pollutants (such as gases) is carried out on a case-by-case basis, occasionally in response to complaints or broader investigations.⁸

Since particle pollution from smoke, caused by wood heaters and landscape burning, is Tasmania’s biggest air pollution hazard, the Tasmania EPA has implemented rules regarding wood-fired heating and cooking within the state. The “Environmental Management and Pollution Control (Smoke) Regulations 2019” (Smoke regulations) were established in 2019, and regulate 3 aspects of wood-fired heating and cooking:

• Compliance with Australian Standards for wood heaters
• Smoke emissions
• Burning of prohibited waste

In general, Tasmania citizens are prohibited from causing an ‘environmental nuisance’, which is constituted by generating excessive smoke emissions from heating and cooking. Tasmanian regulation also limits the types of backyard burning that are allowed, both in order to limit excessive air pollution, and also to ensure a level of fire safety on private properties.

+ Article resources

[1] IQAir. “2019 World Air Quality Report”. IQAir website, March 18, 2020.
[2] Alexander Liddington-Cox. “Tasmania has some of the cleanest air in the world – but it’s not as clean as it used to be”. Business Insider, March 20, 2019.
[3] Nicolas Borchers-Arriagada et al. “Health Impacts of Ambient Biomass Smoke in Tasmania, Australia”. International Journal of Environmental Research and Public Health 17(9): 3262. May 7, 2020. DOI: 10.3390/ijerph17093264.
[4] Tasmanian Government Department of Health. “Reducing smoke”. Tasmanian Government Department of Health website, February, 2020.
[5] Australian Institute for Disaster Resilience. “Tasmania, December 2019-2020, Bushfires – Black Summer”. Australian Disaster Resilience Knowledge Hub, n.d.
[6] John Pickrell. “Smoke from Australia’s bushfires killed far more people than the fires did, study says”. The Guardian, March 20, 2020.
[7] Tasmania EPA. “Real-time Air Quality Data for Tasmania”. Tasmania EPA website, n.d.
[8] Tasmania EPA. “Monitoring air pollution”. Tasmania EPA website, n.d.