Impact of climate change on summer crop production in Australia: insights from the empirical nonlinear autoregressive distributed lag approach

Climate change poses a significant threat to the sustainability of summer crop production in New South Wales (NSW), Australia, a region where agriculture is vital to the economy and rural livelihoods yet increasingly vulnerable to climatic variability. This study employed a Nonlinear Autoregressive Distributed Lag (NARDL) model to investigate the asymmetric short- and long-run effects of maximum and minimum temperatures, rainfall, carbon dioxide (CO₂) emissions, and relative humidity on aggregate summer crop production from 1989 to 2023. The results revealed statistically significant asymmetric relationships: positive rainfall shocks exerted a favorable influence on yields in both the short and long term, whereas rising maximum temperatures were associated with substantial yield reductions. Minimum temperature increases and moderate CO₂ concentrations demonstrated positive effects, while elevated humidity at high temperatures contributed to productivity losses. These findings highlight the complex and differentiated pathways through which climatic factors affect crop performance and underscore the necessity of targeted, crop-sensitive adaptation strategies. Such measures are essential to enhance the resilience and long-term sustainability of the agricultural sector in NSW under evolving climatic conditions.