Poor air quality forecast for western Sydney this afternoon

The air quality in western Sydney is expected to become poor this afternoon as hot temperatures lead to higher ozone pollution.

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The air quality in western Sydney is expected to become poor this afternoon as hot temperatures lead to higher ozone pollution.

Director of Climate and Atmospheric Science at the NSW Office of Environment and Heritage Matthew Riley said air quality levels were expected to become poor due to ozone later around 4pm-5pm this afternoon in western Sydney.

“We’re still expecting to see high ozone in western Sydney and that’s because of extreme temperatures were seeing across western Sydney,” he said.

Mr Riley said ozone pollution was higher on hot days, like those forecast for today and tomorrow.

Today's air quality mapping for western Sydney.

“It actually gets formed within the atmosphere with a whole range of chemical reactions that occur and are driven from sunlight and this is why bright sunny days in summer when it’s hot we get to see the highest ozone pollution,” he said.

“It’s also why ozone peaks in the late afternoon to early evening, because that means there has been plenty of time for all the reactions to occur in the atmosphere and ozone reaches its peak level.”

Yesterday NSW Health issued a statement saying the high temperatures forecast for this week were expected to contribute to high ozone air pollution across Sydney in the coming days.

Director of Western Sydney Local Health District’s Centre for Population Health Professor Stephen Corbett said the chemical ozone was “very different” to the ozone layer in the upper atmosphere and was produced during a chemical reaction which was “amplified by heat and sunlight”.

Professor Corbett said historically the ozone levels were higher in western Sydney compared with the rest of the city.

“We know from past experience that ozone concentrations are generally higher in south western and western Sydney,” he said.

The air quality in western Sydney is expected to become poor this afternoon. Picture: AAP Image/Brendan Esposito

Professor Corbett advised people to stay indoors, not to engage in strenuous activity and for people with asthma or other respiratory diseases to keep their puffers with them.

For more information on ozone visit NSW Health and for the latest updates check the Sydney Air Quali ty Index.

What is ozone?

Ozone is found in two areas of the Earth’s atmosphere; in the upper atmosphere and at ground level. Ground level ozone is the main component of smog and is the product of the interaction between sunlight and emissions from sources such as motor vehicles and industry. It is more readily formed during the summer months and reaches its highest concentrations in the afternoon or early evening.

Sun rise in Sydney ahead of the forcasted heatwave. Picture: John Grainger

How does it affect your health?

Potential health effects from exposure to ground level ozone includes coughing, a sore and scratchy throat or an uncomfortable feeling in the chest, not being able to breathe as deeply or vigorously as you normally would, exacerbation of asthma and chronic respiratory diseases, and increased susceptibility to respiratory infections. Director of environmental health Dr Richard Broome said that “ozone can irritate the lungs, and that people with asthma need to follow their Asthma Action Plan and have their relieving medication with them.”

What can you do?

Limit time outdoors during the heat of the day and in the evening. People with asthma and other chronic respiratory diseases such as chronic obstructive pulmonary disease (COPD) are especially vulnerable to the health effects of ozone and should have their reliever medicine handy. Anyone experiencing severe respiratory distress should seek immediate medical help.