If the rain that deluged Auckland is the ‘new normal’, how are hard-hit growers meant to think about the future? Can they grow anything in the ‘normal’ way again? Vincent asks senior cropping scientist Brent Clothier what he’s telling his clients about the future of food in New Zealand
The rain that last week washed away Pukekohe’s finest, was surprisingly, not a surprise to weather watchers.
“There’s nothing unusual about how it happened,” says Brent Clothier a cropping and environmental scientist with Plant and Food Research (PFR). Speaking over Zoom, a surfboard hanging from the ceiling and the Foxton sand dunes visible through his window, Clothier has as much an eye on the weather as his clients do. “The event was caused by an atmospheric river out in the tropics that was squeezed between two anti-cyclones and hit New Zealand like a bullseye.
“Westport has been hit twice by such a storm. Nelson been hit once, and now Auckland and the whole north east have been hit.”
If there was any novelty, he says, it was the intensity. More than a month’s worth fell in one hour in parts of the city. Too much for Auckland’s creaking infrastructure. Too much for many homes and farms. “The intensity of these atmospheric rivers has increased with climate change. The atmosphere is warmer, it holds more water, and the wind speeds are stronger and they come down and hit a small area to create a deluge.”
Welcome to growing crops in the 21st century.
Senior scientist Brent Clothier: growers are already adapting to climate change but the scale is increasing
Growing food in a drier world
Clothier has seen first-hand the effect of such change on food systems. He’s a principal scientist in PFR’s Cropping Systems and Environment Group and has worked on development projects in the Pacific and Indian Oceans, Africa, the Middle East, and China. When I chat to him he’s packing for Abu Dhabi to advise growers on their diminishing water sources.
“We’ve known about this for some time. But now it’s becoming real for some people.”
Despite last week’s Biblical deluge, the country is getting drier. “Since 1996, there’s been an 11% decline in annual rainfall across New Zealand as a result of climate change. In Northland, that has even been more dramatic – it’s something like 18% lower than it was in 1996.
“At the same time, the warming atmosphere is putting more demand on our plants. It’s a double whammy in the sense that we have less water supplying our reservoirs, rivers, lakes and groundwaters and we’re having greater demand during summer because of our warmer conditions.”
For a nation that depends on irrigation for growing food, this has implications. As MPI notes in a 2021 paper, the food and fibre industries are “by far the biggest out-of-stream users of freshwater in Aotearoa New Zealand, accounting for 75% of water withdrawal consents.” They’re also economically our most significant. “As the largest contributor to export revenue ($48 billion in 2020), a key challenge is to generate the same or more economic activity in a world with less access to water.”
If you managed to avoid any of the hoo-ha around Three Waters reform, this is what’s driving the debate. Water is the new oil.
Four things to know
So what is Clothier telling his clients? Four things.
“The first is the most obvious and yet seemingly the hardest to do: we need to stop emitting the gasses that are creating this problem. We need to reduce our emissions, and eventually, we’re going to have to get CO2 out of the atmosphere.”
With gross emissions still growing, the contribution of food production to GHGs is an open sore. Yes, the world needs food. Yes, well-run farms can sequester CO2. But agriculture is New Zealand’s largest emitter and with energy and transport decarbonising apace, it is set to become the world’s largest.
Meanwhile, the climate continues to warm beyond New Zealand’s ability to change. That means adapting to the new realities. Clothier says growers will need three types of adaptation in their toolkit: tactical, strategic and transformational adaptation.
“Tactical is about making small changes. For example, a grower will notice that the bud-break on the crop is coming earlier, the flowering is earlier and so the harvest has to be organised earlier. It’s a tweak to business as usual.
“Strategic adaptation is more significant. For example, green kiwifruit requires a certain degree of winter chilling to initiate flowering. This is becoming a real challenge in Northland. A tactical action is to use certain chemicals to provoke initiation. But in the future we might have to change to a different kiwifruit cultivar like Gold or move to avocados. Strategic adaptation is about changing the crops or the practice but essentially staying in the same business.”
Transformational adaptation is about a complete change of land use. The green kiwifruit operation might move to Central Hawkes Bay where there are still frosts. Or it might mean cultivating protein in the lab or growing burger patties through precision fermentation.
Changing land use, of course, brings its own set of risks. Under current incentives, many farmers are turning to forestry for carbon credits, which neither feed people nor provide high emissions reductions. Tragically, great tracts of those fertile Pukekohe soils are being given over to bland housing estates as growers weigh the cost of growing food.
Managing change is nothing new, says Clothier, but it’s perhaps the scale of the change that feels so daunting. “It’s a real challenge for growers and farmers to think about climate change because they live in the weather. So they’re very, very astute in terms of their knowledge of weather. But climate is longer. It’s longer than memories. People say ‘it’s the worst storm I can remember’ but that’s not very long.
“But I’m an optimist. It will be difficult but there are solutions.”
