Methane from coal mines a climate test for Aussie PM

SYDNEY • Australia's coal mines cause more planetary warming in a typical year than emissions from all of the country's cars.

If Prime Minister Anthony Albanese wants to meet tougher climate targets, he will need to fix that.

Satellite data suggests the best place to start is the Bowen Basin, the major coal hub in Queensland state and an area where scientists have estimated the methane intensity per unit of production is 47 per cent higher than the global average.

A satellite earlier this month spotted a plume of the potent greenhouse gas that geoanalytics firm Kayrros estimated originated within about 25km of coal mines operated by Anglo American, Stanmore Resources and BHP Mitsubishi Alliance, known as BMA.

The former two companies did not answer questions from Bloomberg asking if their mines emitted methane the day of the satellite observation. BMA said it estimates and publicly reports emissions in accordance with national requirements.

"Methane leaking from coal mines has been ignored for many years, but tackling it is the 'low-hanging fruit' in Australia's effort to combat climate change," Dr Sabina Assan, an analyst with the environmental think-tank Ember, wrote in a report released this month.

The Bowen Basin has become a global example of the disparity between reported coal mine methane emissions and independent measurements, according to the report. The powerful greenhouse gas can leak from underground and open-cut coal mines and has 84 times the warming power of carbon dioxide during its first two decades in the atmosphere.

The most recent release, observed on June 3 by the European Space Agency's Sentinel-5P satellite, was estimated to have an emissions rate of 12 tonnes of methane an hour and could have come from several mines, according to Kayrros.

Coal production typically runs 24 hours a day, so methane is often emitted constantly from mines. Release levels might fall during maintenance, or rise if miners hit a gas pocket.

If the rate estimated by Kayrros was consistent for a year, the gases would have the same short-term warming impact as the annual emissions from roughly 1.9 million United States cars.

Australia's new government, voted into office in May, last Thursday confirmed an election pledge to lower carbon emissions by 43 per cent from 2005 levels by 2030, tightening a previous commitment for cuts of 26-28 per cent.

In February, Australia disclosed that it had revised the method used to calculate methane pollution from open-cut coal mines and said the change means total national emissions were on average 0.3 per cent higher than previously stated for each year since 1990.

That revision was prompted by the use of satellite observations, which have improved capacity to estimate emissions, the government said. The change is not currently reflected in national greenhouse gas reporting legislation.

BMA, which did not use the updated methodology, said that based on site-specific measurements of methane and CO2 content in the coal seams and surrounding strata at its Broadmeadow, Peak Downs and Caval Ridge mines, they cumulatively emitted about 3.32 tonnes of methane an hour on June 3.

Australia's Department of Industry, Science, Energy and Resources said coal mine operators are required to estimate and report company and facility level greenhouse gas emissions under reporting guidelines and that the country's Clean Energy Regulator publishes reported emissions data annually.

BLOOMBERG