Climate change impact on grape ripening in Murfatlar vineyard

Abstract

Climate change is exerting a significant influence on viticulture, leading to altered phenological stages, shifts in grape ripening, and major challenges for maintaining wine typicity. This study evaluates the long-term impact of climate variability on grape maturity in the Murfatlar vineyard, southeastern Romania, one of the country’s most representative wine regions. A comprehensive dataset was analyzed, integrating harvest initiation dates over two decades (2004–2024), grape composition at harvest for six cultivars across ten vintages (2015–2024), and berry ripening dynamics monitored during the last seven years (2017–2024). Results indicate a consistent advancement of harvest dates, with initiation occurring nearly three weeks earlier in 2024 compared to the early 2000s, at an average rate of 8.7 days per decade. Grape acidity displayed a steady decline across cultivars, reflecting the direct effect of higher temperatures on organic acid degradation. By contrast, sugar accumulation showed pronounced interannual variability without a clear upward trend, suggesting that heat and drought stress often limit carbohydrate assimilation despite accelerated ripening. The 2024 vintage further illustrated this decoupling: early and rapid sugar accumulation was followed by stagnation and dilution due to late-season rainfall, while berry weight decreased, with cultivar-specific responses. Overall, the findings highlight that the primary challenge for Murfatlar viticulture is not excessive sugar accumulation, but the accelerated loss of acidity, which compromises freshness and balance in wines. Adaptive strategies, including canopy and water management, optimized harvest timing, and innovative oenological practices, are therefore essential to safeguard grape quality and preserve the typicity of local cultivars under ongoing climate change.