As El Niño strengthens across the Pacific, Australian farmers could face fierce frosts

As El Niño strengthens across the Pacific, Australian farmers are increasingly bracing for severe frosts, a concern that once seemed distant but is now a growing reality. In Papua New Guinea, crops have been decimated by a combination of drought and frost, leaving communities without food and water, reminiscent of past frosts in 1972, 1997–98, and 2015–16.

El Niño, a naturally occurring weather phenomenon, is driving intense temperature variations and stronger winds across the Pacific, which may bring more frequent and severe frosts to farming regions in Australia. Frost forms after a cold, clear, and windless night, with clear skies allowing heat to escape and soil temperatures to plummet.

Dry conditions expedite cooling due to the diminished heat storage capacity of parched soils. Cold air flows into valleys, creating frost hollows, where stagnant, dense air can lead to frost. If the minimum forecast temperature drops to 3°C or below, a frost is likely, even if the air temperature remains above freezing. Frost can wreak havoc on crops, causing water in plant cells to freeze and rupture, resulting in irreversible damage or death, particularly during critical stages like flowering.

Australian farmers are on high alert, with the Birchip Cropping Group reporting a robust harvest after a wet winter, only to be reminded of the frost risks by the Bureau of Meteorology's multiple frost warnings. While some southern Mallee farmers have suffered minor crop damage, most Australian growers have fortunately avoided significant frost damage this year.

Farmers can mitigate frost risks by selecting appropriate crop varieties, monitoring weather warnings, and identifying frost-prone areas. Governments and international organizations must continue funding weather forecasting services and agricultural research to help farmers adapt to the evolving climate challenges.