The paper this article is based on informs us that ‘The Pacific Walker circulation (PWC) has an outsized influence on weather and climate worldwide. Yet the PWC response to external forcings is unclear’. Under a headline saying: ‘Greenhouse gases are changing air flow over the Pacific Ocean, raising Australia’s risks of extreme weather’, the article here offers almost nothing to support an argument for any human-caused climate effects ‘in the industrial era’. The paper is somewhat embarrassing for climate models: ‘Most climate models predict that the PWC will ultimately weaken in response to global warming. However, the PWC strengthened from 1992 to 2011, suggesting a significant role for anthropogenic and/or volcanic aerosol forcing, or internal variability’. So that role could be anything or nothing, but the models trended the wrong way anyway. The search for ‘anthropogenic fingerprints’ continues.
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After a rare three-year La Niña event brought heavy rain and flooding to eastern Australia in 2020-22, we’re now bracing for the heat and drought of El Niño at the opposite end of the spectrum, says The Conversation (via Phys.org).
But while the World Meteorological Organization has declared an El Niño event is underway, Australia’s Bureau of Meteorology is yet to make a similar declaration. Instead, the Bureau remains on “El Niño alert.”
The reason for this discrepancy is what’s called the Pacific Walker Circulation. The pattern and strength of air flows over the Pacific Ocean, combined with sea surface temperatures, determines whether Australia experiences El Niño or La Niña events.
























