Phenological and Oenoclimatic Indices Used in Viticulture: A Review of Recent Literature (2010–2026)

Climate strongly influences grape phenology, wine quality, and the suitability of regions for grapevine cultivation, and numerous bioclimatic, phenological, and oenoclimatic indices have been developed to characterize viticultural climates. A structured literature review was conducted to identify and synthesize research on phenological and oenoclimatic indices in viticulture. Comprehensive searches were performed across multiple databases (Web of Science, Google Scholar, SciSpace and PubMed) from 2010 to 2026. Studies were screened using six predefined criteria focusing on viticultural system relevance, bioclimatic index application, phenological outcomes, and regional characterization. From 842 initially identified records, 273 studies were included after deduplication and two-stage screening. The review identified 34 distinct bioclimatic, phenological, and oenoclimatic indices applied across more than 60 countries and wine regions worldwide. The most frequently applied indices include the Huglin Index, Winkler Index, Cool Night Index, Dryness Index, Growing Season Temperature, and Growing Degree Days. The identified indices serve multiple purposes, including viticultural zoning, climate change impact assessment (the dominant application, about 44% of studies), variety selection, and harvest timing prediction. Thermal indices are considerably more developed than hydric and extreme-event indices, and most indices describe the climatic potential of a region rather than conditions in individual vineyards. Future research should focus on transparent reporting of index calculations, validation of indices in diverse climatic contexts, and the integration of multi-index approaches with remote sensing and other digital tools.