Climate change: Impacts and adaptations for grapevine production in New Zealand

Abstract

Aim: To explore the current state of knowledge of impacts on climate change on grapevine phenology and ripening. Methods: Suitability under future climate change scenarios of the top-10 international grapevine cultivars was investigated on a global scale by combining phenological and future climate models. Changes in cultivars were characterised for the whole of New Zealand. For New Zealand regions, the impacts of climate change were assessed using a similar methodology specific to the national scale, and the results for current cultivar-region combinations were compared. Results/Findings: New Zealand will see increased potential suitability of most key cultivars grown here today but this may be a result of shifting regions. Advances in key phenological stages such as flowering and veraison are projected to be up to three weeks by 2050 under climate scenarios, which project an increase in temperatures by 1.5°C by 2050, and up to 4°C by 2020. Current cultivar-regions combinations may advance outside the current ‘ideal’ window of timing for key phenological events. However, there is the opportunity to consider adaptation practices (delayed pruning, canopy management) to help counter these advances. Conclusions: Cultivar diversity represents a sustainable adaptation strategy for climate change in New Zealand with increased suitability of later ripening cultivars. To retain current regional –cultivar combinations, other cultural practices of adaptation will need to be considered.