U.S. Air Quality

International: Massive dust storm and extremely hazardous air quality in southeast Australia

New South Wales, Australia, in the southeast part of the country, experienced a dust storm of massive proportions today. The dust, exacerbated by drought and combined with some smoke, was picked up by gale force winds from an intense low pressure system. The dust poured from the interior of the country toward the coast, inundating Sydney before moving over the Tasman sea and the Indian ocean. The best way to see this is to look at the MODIS images from yesterday (left) with the beginning of the dust visible and mixed with long smoke plumes, compared to today (right) where the land is barely visible under the dense yellow-orange dust.

Air quality readings from the New South Wales Government Department of Environment, Climate Change and Water indicated PM10 24-hour average concentrations between 1500-2500 ug/m3. The AQI values were over 4000 (when 200+ is considered hazardous). The Sydney Morning Herald reported canceled flights and major health concerns, although it was starting to clear this evening.

For those interested in forecasting and air quality policy, there was some political controversy about the 'good' air quality prediction that was on the New South Wales government website even after the event started. These kinds of major isolated events are difficult for models to predict, thus it is important for forecasters to rely on a wide range of monitoring information.