Short CommunicationPrecipitation intensity under a warming climate is threatening some Italian premium wines
Graphical abstract
Introduction
The wine industry has had cultural and economic importance in Europe for centuries and now may be threatened by climate change (Cook and Wolkovich, 2016; Fu et al., 2014; Sherry et al., 2007; Cleland et al., 2007). Europe is the largest global producer, with 56.3% of the total in 2017, and Italy produces more wine than any other country, accounting for >30% of the European volume (EU Wine Market Data Portal, 2018). In the past fifteen years, European wine production has shifted from cask and low-cost bottle wine toward premium wines, with 82% of the EU wine grape area now used in quality, premium wines (Agriculture, forestry and fishery statistics, 2017). In Italy, as well as other wine-growing countries, premium wines have been produced for centuries. Several studies have shown that premium wine production and climate are linked (White et al., 2006; Jones et al., 2005).
Premium wines can provide a good indicator of climate change for several reasons. First, the premium wine grapes are sensitive to climate changes, requiring a narrow climate range that excludes both extreme heat and extreme cold (White et al., 2006). Second, some premium wines have been produced the same way in the same location for centuries (White et al., 2006; Chuine et al., 2004). Third, some vintners have kept long-term records of annual wine production (Meier et al., 2007; Jones and Davis, 2000). One of the most well-documented aspect of premium wine production is the grape harvest date (GHD), which is tightly linked to grape maturation (Meier et al., 2007; Sun et al., 2018). The strong connection between GHD and temperature serves as a proxy to reconstruct past climate (Meier et al., 2007; Sun et al., 2018) as well as a predictor of the impact of climate change on wine quality and a guide for adapting wine production to a warmer climate (White et al., 2006; Wolkovich et al., 2018). Early GHD is always associated with temperature increases during the growing season, whereas more precipitation, in terms of the total amount of rain or the average rain measured in a certain period, generally delay harvest (Cook and Wolkovich, 2016; Fu et al., 2014; Sun et al., 2018). Thus precipitation must be considered as well as temperature when analysing these long-term records of a premium wine GHD (Ciais, 2005). Although the impact of precipitation amount and drought on wine grape phenology have been investigated, knowledge of the role of precipitation characteristics is very limited (Cook and Wolkovich, 2016; Wolkovich et al., 2018).
Precipitation can be characterized for a growing season as total amount of rainfall, number of the rainy days (NRD), which is the number of days with precipitation equal or above 1 mm, or precipitation intensity, which is the total amount of precipitation divided by the NRD. These characteristics can vary from region to region and can respond differently to climate change (Allan and Soden, 2008; IPCC, 2013; Trenberth, 2011; Giorgi et al., 2014). However, there is a general consensus that the annual precipitation (mm/yr) has changed little or not at all for 76% of the global land surface (IPCC, 2013; Trenberth, 2011). In contrast, observations confirm that the number of heavy precipitation events has increased over much of the global land surface (Fischer and Knutti, 2016; Trenberth, 2011; Hannah et al., 2013; van den Besselaar et al., 2013). Model simulations for future scenarios of global warming predict that heavy precipitation events will become more frequent and more intense (Donat et al., 2016; Trenberth, 2011; Giorgi et al., 2014; Rajczak and Schär, 2017). Severe precipitation causes flooding, landslides, agricultural damage and loss, including vineyard damage and loss.
Several previous studies of the relationship between climate and wine production have used multiple grape varietals. However, each varietal can have different quality standards, resulting in grape harvest dates at different levels of maturation from year to year, and a different response to climate stresses. In addition, over the years, many vineyards have changed their cultivation techniques, such as using irrigation and fertilizers, and these changes could alter the GHD (Webb et al., 2012; Thorne and Vose, 2010). Finally, some of these studies use global meteorological data, which may not accurately represent the climate at the vineyards (Thorne and Vose, 2010). All of these issues can mask a possible correlation between GHD and climate change. We address these issues by analysing the GHD of a premium white wine (Trebbiano d'Abruzzo) from a single vineyard. This wine won the best wine of Italy award in 2012 (Xoplaki et al., 2003) and has been constantly ranked in the top 10 of Italian wines for the past decade. The winery has used the same cultivation practices since 1650, with no irrigation or fertilization, and has a long-term record of GHD. As a result, it should be possible to determine the climate sensitivity of the GHD for this wine without biases due to changes in cultivation practices or grape varietals. The goal of this work is to explore if the advance of the recorded GHD is triggered by the observed changes of climatological parameters. In particular which of the different meteorological parameters and climatological indexes can be used to describe the GHD changes. Considering the observed and predicted increase for the future of severe precipitation events, we introduce another parameter (precipitation intensity) among those usually considered to drive GHD, to assess if this characteristic of precipitation plays a role in the advance of GHD.
Section snippets
Data sources
The GHD data come from the winery records, which date back to 1818, although two multi-decadal gaps occur in the mid-to-late 1800's and the early-to-mid 1900's, but cover every year since 1959 (Fig. 1). The gap from 1840 to 1880 was due to the political instability caused by the Italian unification; the gap in the 1900's was due to the First and Second World Wars. Valentini's family that has run the winery since 1650 did not record the GHD prior to 1820. Documents at the winery attest that the
Results
The link between GHD and climate parameters, in our results, is evaluated for a single wine grape varietal to minimise possible different response of plants to climate stress and with local meteorological data to reduce the effect of data not representative of the local state. Prior to 1980, there is not a clear trend; the GHD ranges between the 2nd of November (the absolute latest GHD on 1846) and the 30th of September, whereas after 1980, the GHD record shows a trend strongly decreasing
Discussion
Using the harvest dates and the multivariate regression analysis, we found that for growing seasons since 1960, annual harvest dates of the white wine have been getting early as temperature increases (−5.92 days °C−1) and more intense precipitation events occur (−1.51 days/(mm/NRD)). Our results indicate a fundamental role of the precipitation intensity in the grape wine phenology that reinforces the impact of the increasing temperature. While the effect of temperature increase can be
Conclusion
This study contributes to understand how climate change is influencing crops and agriculture. Our analyses confirm that global warming is affecting premium wines in Central Italy, inducing early GHD at similar rate to what observed in France, Switzerland and Spain. Moreover, we found that the increase of precipitation intensity, observed in the last decades, is the other factor triggering the GHD advance. Even if the impact of precipitation intensity, not yet considered in previous studies of
Acknowledgments
Many thanks to Francesco Paolo Valentini for providing the wine-grape harvest data, for giving access to the documents of the archives of his vinery and family, and for helpful discussion about wine and climate. We thank Mario Cerasoli and Antonio Iovino of the Centro Funzionale of the Abruzzo Region for providing the meteorological time series and for all the details about the meteorological stations, and Manuela Rastelli who helped in revising and improving the English of the manuscript.
Author contributions
P.D.C. designed the research, conducted the analysis and model simulations. P.D.C. wrote the original draft. P.D.C., W.H.B. and E.A. wrote the reviewed manuscript. E.A. processed the local meteorological data and conducted the homogenization. All authors discussed the study results and reviewed the manuscript.
Declaration of Competing Interest
The authors declare no competing financial interests and no competing non-financial interests.
References (36)
- et al.
Shifting plant phenology in response to global change
Trends Ecol. Evol.
(2007) The Winesider Best Italian Wine Awards
Agriculture, forestry and fishery statistics 2017 edition
(2017)- et al.
Atmospheric warming and the amplification of precipitation extremes
Science
(2008) - et al.
Homogenization of instrumental time series of air temperature in Central Italy (1930−2015)
Clim. Res.
(2019) - et al.
Trends in European precipitation extremes over 1951–2010
Int. J. Climatol.
(2013) - BEST. 2019 National Center for Atmospheric Research Staff (Eds). Last modified 11 Jan 2019. "The climate data guide:...
- et al.
Historical phenology: grape ripening as a past climate indicator
Nature
(2004) Europe-wide reduction in primary productivity caused by the heat and drought in 2003
Nature
(2005)- et al.
Climate change decouples drought from early wine grape harvests in France
Nat. Clim. Chang.
(2016)
Dai Global Palmer Drought Severity Index (PDSI). Research Data Archive at the National Center for Atmospheric Research
More extreme precipitation in the world's dry and wet regions
Nat. Clim. Chang.
Observed heavy precipitation increase confirms theory and early models
Nat. Clim. Chang.
Recent spring phenology shifts in western Central Europe based on multiscale observations
Glob. Ecol. Biogeogr.
Changes in extremes and hydroclimatic regimes in the CREMA ensemble projections
Climate Change
Climate change, wine, and conservation
Proc. Natl. Acad. Sci. U. S. A.
Decadal trends in the North Atlantic oscillation: regional temperatures and precipitation
Science
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