Challenges and Opportunities for New Zealand Agriculture under Climate Change (2022 update)

Future climate is likely to have a major impact on the primary sector, and has the potential to drive major shifts in land use as previously suitable climatic conditions change. Potential impacts on the primary sector can be due to chronic effects (long-term changes in climate conditions) or acute effects (extreme events). The seasonality and spatial suitability of some crops will change. For example, maize crops could be planted earlier to minimise negative climate change impacts. Grapes could flower up to 2 weeks earlier for the Sauvignon Blanc variety in Marlborough, and 4 weeks earlier for Pinot Noir in Central Otago by mid-century. New areas could become suitable for grapes as the frost risk decreases. Various climate change projection scenarios show a general pasture increase in the spring but declines in the summer. Pasture yields in New Zealand are projected to increase, the seasonal pattern will probably change, with more favourable conditions in winter and spring, and less growth projected in summer due to an increase in water demand. Nitrate leaching could be higher and more variable. Erosion rates are also likely to increase in parts of the North Island. Heat stress could increase, affecting animal welfare and milk production from dairy cows. The level of adaptation needed will depend on the global warming trajectory and future climate change projections. These measures can range from tactical, to strategic or transformational changes. We plan to adopt the IPCC's risk-assessment approach, combining hazard, susceptibility, and adaptive capacity for each major risk. Biophysical models can help assess the susceptibility of crops to future climate, with the hazard described by the likelihood of extreme events occurring in different parts of the country