The impact of drought in Hurunui in North Canterbury. Photo: Supplied / Dan Hodgen
The ebbs and flows of farming are expected to be exacerbated by future climate change effects, including more volatile weather and strained water resources, a new study has found.
Research consultancy firm Kōmanawa Solutions ran 295 million weather simulations with past weather data on a catchment in North Canterbury to understand how climate change will impact farmers' bottom lines in the next decade.
It combined climate data, pasture growth models, farm economic models and stream health models to identify where farmers' resilience was likely to be "overwhelmed" by climate and global volatility.
The purpose of the five-year project - supported by the Ministry for Primary Industries' Sustainable Land Management and Climate Change Fund - was to help farmers, regional councils, government and banks plan ahead for adaptation support.
The report found farm production and profitability were already affected by climate change, and the risk of financial instability was set to increase over time.
Water resource scientist and Kōmanawa founder Zeb Etheridge, who wrote the report, said water resources will be under greater pressure in a warming climate.
"As our climate continues to become more volatile, we expect the effects to become much more negative, with bad years becoming worse and more frequent," Etheridge said.
Zeb Etheridge Photo: SUPPLIED/JULIETTE CAPALDI ETTA
The report found irrigated dairy farms were particularly at risk because water supplies were expected to become less reliable in areas with high usage pressures.
Etheridge said regulators should not look back to historical climate and river flow data to understand climate risks, but forward to understand the changing climate.
"That's really what we've been trying to do with this work is give people an idea of how different things could be and give them the information to make more informed decisions."
North Canterbury is home to a large irrigation scheme off the Waimakariri River, which is restricted during times of low river flows.
However, a new water storage facility proposal north of the Hurunui River by firm Amuri Irrigation is being considered by the Canterbury Regional Council.
The Hurunui River Photo: 123RF
Etheridge said North Canterbury farmers could reduce their stocking rates to better manage climate variability in the next decade.
"Our research says that in a lot of instances, dropping your stock numbers is probably going to make you a bit more resilient and improve your financial performance long term.
"Farmers might not make quite so much money in those good years, but they'll be much more cushioned from the effects of those bad years."
He said storing water will provide some resilience to farmers, but was not a silver bullet.
"Putting a water storage system on your farm like a pond to give you some more irrigation reliability, that can cushion you from the effects of climate change, but it can also increase your vulnerability to the broader volatility that we see in commodity prices, interest rates and so on. So you can increase your exposure on a financial side.
"It's a big investment and I think people should be very wary about making those decisions from looking at past records of hydrology and climate and assuming that things are going to be the same, because they're going to be different. The question is just how different."
The research will be presented at the international Adaptation Futures conference in Ōtautahi/Christchurch from October 13-16.
