Response of viticulture‐related climatic indices and zoning to historical and future climate conditions in Greece

Abstract

Climate and viticulture are indisputably linked and thus knowledge of the predominant weather and climate conditions of a given area is essential for optimum variety selection, viable production and overall wine quality. In this study, an assessment of the current (1981–2010) and future conditions (2021–2050 and 2061–2090) through principal climatic elements and six bioclimatic indices (i.e. Growing season average temperature, growing degree‐days, Huglin index, biologically effective degree‐days, dryness index and cool night index) at 23 weather stations proximal to the key mainland, coastal and island viticultural areas of Greece was performed. Mainland locations were generally colder due to their wider variety of terroir aspects and elevation, while coastal locations and islands faced proportionally more extreme temperatures and drier conditions. Trend analysis revealed that minimum temperatures increased at higher rates than the respective maximum temperatures at most locations. Climate change scenarios derived from the regional climate model RegCM4 suggested significant shifts towards warmer and drier conditions across all locations in the future. These conditions are very likely to advance phenology and harvest beyond what is considered suitable and will likely have detrimental impacts on wine quality. Differences in impacts will likely be seen between wine areas currently cultivated with early ripening (reducing variety suitability) versus those with later‐ripening (increasing consistency in ripening) varieties. Overall, the changes projected for the future climate will challenge the Greek wine industry to increase its adaptive capacity through better understanding of temperature thresholds for the varieties grown and the adoption of new cultivation techniques and strategies.

Bioclimatic conditions of the Portuguese wine denominations of origin under changing climates

“…The expected warming and drying results in shifts of the DO/sub‐regions to higher classes. These results are in agreement with the warming and dryness reported in other southern European countries (e.g., Duchêne and Schneider, ; Neumann and Matzarakis, ; Lorenzo et al ., ; Dunn et al ., ; Koufos et al ., ).…”

“…Thus, climate change can bring risks to the quality/characteristics of wine, but also opportunities for cooler regions (Neethling et al ., ) The dependence of grapevine varieties on specific climatic conditions and the perennial nature of grapevines limits the adaptation of the current DO/sub‐regions to climate change (Webb et al ., ; Metzger and Rounsevell, ; Dunn et al ., ). In areas with the most negative impacts, potential adaptations include (a) modifications in vine training and canopy architecture, (b) adjustment of vine practices, for example, irrigation and soil management, (c) moving vine cultivation to new areas at higher elevations and/or to north‐facing slopes, (d) varying wine style preferences (e.g., red or sweet wines as an alternative to white wines) (Koufos et al ., ) or (e) the growth of new grapevine varieties in DOs that have greater adaptability with future warmer and drier climates.…”

“…Excessive precipitation in late spring can impact flowering and fruit set and in summer can adversely affect berry quality parameters and may also trigger increases in disease pressure in vineyards (Cyr et al ., ). On the other hand, severe dryness, particularly during the early stages of grapevine annual growth cycle, may also cause adverse effects on grapevine growth, development and yields (Fraga et al ., ; Koufos et al ., ). Even though other atmospheric parameters are also important for grapevines, such as solar radiation, wind and air humidity levels, temperature and precipitation are the leading forcing variables in rainfed, temperate climate viticulture.…”

Refining the growing season temperature parameter for use in winegrape suitability analysis

“…In Australia, Hall and Jones (2009) found that the area with a GST between 13 and 21°C may reduce by up to 50% by 2070, which could result in 21 out of the 61 Australia's recognised wine regions sitting outside the GST limits. Internationally, studies have been conducted in New Zealand (Anderson et al 2012), America (Jones 2005, White et al 2006, Hall and Jones 2009, Diffenbaugh and Scherer 2013, Schultze et al 2016, Schultze and Sabbatini 2019), Canada (Shaw 2017), Europe (Jones and Alves 2012, Neethling et al 2012, Koufos et al 2018) and the United Kingdom (Nesbitt et al 2018), have created a growing body of work which indicates that, as the global air temperature warms, viticultural zones will invariably change. On a global scale, Hannah et al (2013) used GST as a metric to assess the suitability of winegrapes in the future for viticulture and concluded that this might decrease by 25 to 73% in major wine producing regions internationally by 2050.…”

Anthocyanin content and composition in four red winegrape cultivars (Vitis vinifera L.) under variable irrigation

“…In Greece, vineyard area under irrigation has been steadily increasing during the last three decades. Moreover, since temperature and rainfall patterns are predicted to change, increasing the risk of drought in Greece's viticultural regions (Koufos et al, 2018), supplemental irrigation will greatly affect the ability of existing varieties to ripen fruit. The aim of this study was to determine and compare anthocyanin content and profile under variable irrigation regimes in four red grape cultivars (Vitis vinifera L.), namely Agiorgitiko and Xinomavro, alongside the well studied French cvs.…”