The La Niña weather cycle is here for another year. What does that mean for our grain harvest?
The sky is blue, it’s hot but not too hot, and there’s a gentle breeze in the air. It’s perfect harvest weather.
“I’m happy, like a pig in mud,” laughs Brett Hosking, a grain grower from Quambatook in northern Victoria and chair of Grain Growers, a national body representing Australian grain farmers.
But Hosking is all too aware that while he’s relishing hot, dry weather ideal for harvesting his family’s barley, wheat, lentils and canola, farmers further north are looking at a different forecast. In late November, the Bureau of Meteorology announced La Niña is underway in the Pacific Ocean.
For eastern, northern and central parts of Australia, La Niña means a wetter than normal period due to rainfall becoming focused in the western tropical Pacific.
The Bureau says La Niña is also associated with an increased chance of cooler-than-average daytime temperatures for much of Australia and an increase in the likely number of tropical cyclones and earlier first rains of the northern wet season.
La Niña is just one part of a naturally occurring weather cycle known as the El Niño-Southern Oscillation (ENSO), a shift in ocean temperatures and weather patterns along the equator in the Pacific Ocean. A La Niña event can often last for two years (as is the case currently). It always begins early in the year, continuing until autumn the following year.
Hosking says the Bureau’s announcement was unlikely to surprise farmers around Australia’s northern and eastern parts, who have already seen unseasonably high rainfall and weather events.
“What we’ve seen in New South Wales is extreme rainfall events of 50 to 100 millimetres and sometimes more, falling very heavily and quickly, causing localised flooding, which, as the events combine, becomes major flooding,” he says.
The Bureau constantly monitors climate drivers and communicates changing conditions on a scale from La Niña to El Niño (the opposite weather pattern to La Niña, which predicts hot, dry weather). It shifted its La Niña “watch” mode to La Niña “alert” mode in October, indicating a 70% chance of La Niña. The November announcement confirms La Niña is here.
For farmers in areas most affected (NSW, parts of South Australia and Queensland), La Niña will likely have a huge impact on what has otherwise been predicted to be a bumper harvest due to high spring rainfall – in early December, the Australian Bureau of Agricultural and Resource Economics and Sciences (ABARES) predicted Australia’s winter crop production to reach a national record of 58.4 million tonnes, due to favourable spring conditions.
ABARES concedes, however, that “a series of heavy rainfall events during November has delayed the harvest of winter crops across New South Wales and Queensland, likely leading to a fall in grain quality in unharvested crops.”
According to Hosking, the late and heavy La Niña rainfall impacts grain growers in a number of ways. While some may lose entire crops, others who can harvest may see their grain drop in quality.
“Heavy rainfall will flatten crops; they’ll be knocked to the ground,” he says. “But that’s not the biggest concern. The crops are effectively seeds that are ready to germinate and we need to get them out of the ground before they do. When we get humid weather following those rainfall events, those seeds will actually germinate in the heat, before we want them to.”
Early germination lowers the weight of the grain as well as reducing its nutritional quality, both of which result in lower prices.
“It can affect the milling quality of wheat,” says Hosking. “It makes it not as suitable for baking bread, for example, and becomes more of a stock-feed product.”
For barley, early germination affects the malting process.
“The malting process relies on putting the grain into a vat of water and germinating the grains,” says Hosking. “If that process has already begun before the barley gets there, the process is not as consistent and effective, which deteriorates the quality of the grain and the price.”
“The impact is going to be massive. We’re looking at hundreds of millions of dollars of loss. It could even be the $1 billion mark.”
Peter Holding, farmer and outreach officer for Farmers for Climate Action, agrees but says the loss is not looking as bad as he thought it might be.
“We were getting close to $400 a tonne for top-quality wheat,” he says. “I thought it might fall to $150 for damaged wheat, but it appears to be holding at $250 a tonne.”
Holding says high prices for grain, which are due to an international shortfall after floods and drought overseas, are looking to be the saving grace. It’s a far cry, however, from the bumper season farmers were hoping for.
“It’s a very rare year that you get high prices and high yield combining, but that’s what this harvest was looking like,” he says. “It’s a real whack in the guts.”
While the Bureau describes La Niña as a naturally occurring shift in weather patterns, Hosking notes the increase in extreme weather within these weather patterns. Major flooding events are on the increase, he says. He’s seen “dry years turn into drought years and wet years turn into flood years”.
“Weather patterns are getting more extreme when they do hit,” he says. “Where once we’d get isolated heavy storms, we’re now getting widespread heavy storms. Where once we would get short, sharp droughts, we’re now getting longer-term and more extreme droughts.”
So what’s being done to mitigate the impacts of these high rainfall events on our grain crops?
“Australian grain producers contribute a significant portion of the estimated $200 million that’s invested annually into research, development and extension projects and initiatives,” says Barry Large, chair of Grain Producers Australia, a body that represents grain producers and ensures the compulsory levies that farmers contribute to research each year result in enduring profitability for grain producers.
“This research is aimed at helping grain producers respond to challenges such as fluctuating seasonal conditions.”
Examples of this include plant breeding and new crop varieties that can cope with seasonal stress, as well as better prediction of weather factors such as frost. Large says farmers are collecting more and more data from their fields to help them cope with changing climate.
“Farmers are collecting so much more data now,” he says. “It’s called precision agriculture and it involves tweaking things like how much fertiliser is needed for a particular crop in a particular season, in response to how a particular paddock is performing. You can map those products on a field-by-field basis.”
Holding says the most critical response to weather events such as widespread flooding (and drought) is to go back to the root of the cause by reducing emissions.
“I would’ve thought the first thing to do is not make the situation worse,” he says. “That means take action on reducing emissions, which means rapidly transitioning away from fossil fuels.”
Holding points to documented links between the release of carbon dioxide into the atmosphere and stronger ocean currents such as those that prompt La Niña.
He worries about climate change contributing to “a perfect storm” of factors in the coming 18 months, including lost crops and predicted increases in interest rates, that could have a devastating impact on farmers’ income.
Hosking says La Niña is not all bad.
“Typically, we like La Niña in agriculture,” he says. “Often it provides above-average rainfall or a summer rainfall event where we’re able to capture moisture in the soil for future growing seasons.”
Hosking argues that Australian farmers are adaptable and find ways to capture and utilise unexpected rainfall events for future seasons. But rain during harvest is a different story.
“It’s very difficult to deal with extreme rainfall at the point of harvest, when the crop is ripe and ready to harvest,” he says. “There’s very little the grower can do at that point.”
Meanwhile, Hosking is “making hay while the sun shines”. The combine harvester’s bright headlights can be seen in the field until 11pm, and in the morning he’ll be back at it by 6am.
“I could keep going, but I’m getting a bit old for that kind of caper,” he says with a chuckle – and no sign in his voice of slowing down anytime soon.
Originally published by Cosmos as The fluctuating fortunes of La Niña
Bron Willis is a freelance environment, science and sustainability writer based in central Victoria.