A Climate Assessment for the Douro Wine Region

 

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index foreword 1 executive summary 2 introduction 4 weather and climate structure for wine quality and production 4 climate suitability for winegrape cultivars 5 climate variability in wine regions 7 climate change viticulture and wine 9 the douro wine region 15 data and methods 18 historic climate normals 18 douro wine region stations 20 regional circulation and weather regimes 21 spatial climate historic 22 spatial climate future projections 23 results and discussion 24 historic climate normals 24 douro wine region stations 27 regional circulation and weather regimes 41 spatial climate historic 45 spatial climate future projections 58 conclusions 72 acknowledgements 76 literature cited 76 appendix 83

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foreword advid associação para o desenvolvimento da viticultura duriense association for the development of viticulture in the douro region is a non-profit association founded in 1982 by a group of companies involved in the production and marketing of wines from the douro wine region dwr advid aims to study demonstrate and disseminate vinegrowing and wine-making techniques appropriate to the specifics of the region so as to encourage the competitiveness of its wines in the domestic and international markets in 2008 the portuguese government recognized the douro region wine cluster as a collective efficiency strategy compete application furthermore the portuguese government named advid the management entity and driving force behind implementing the strategic goals under the plan of action that was presented the impact of climate change on wine production was considered one of the cluster s flagship projects for its economic importance for the wine industry this flagship project seeks to respond to a number of advid s concerns and activities underpinned by a diagnosis report published in 2007 containing proposals that provided the basis of the terms of reference of this topic the report was prepared and duly reflected by the douro wine industry for an integrated consequent and consistent approach to the search for solutions working in conjunction with portuguese and international universities the intention was to respond to a need determined by the business sector linked to the wine industry in the region in order to understand the range of potential impacts and possible solutions for climate change scenarios at the regional and local scale to document and better understand the characteristics of climate in the douro region advid relied on the collaboration of the prestigious american scientist prof gregory jones southern oregon university a specialist in climate structure and suitability for viticulture and how climate variability and change influence grapevine growth wine production and quality to carry out the project the work consisted of analyzing stabilizing and lending credibility to existing climate databases and providing new approaches for the interpretation of the regional climate contributing to its better understanding a condition essential for the projection of future climate scenarios currently this flagship project is founded on three mutually complementary measures evaluating the climate of the douro region ­ analysis of the climatic conditions of the past present and future for wine production definition of more-effective adaptation strategies and prediction of the consequences for the quality of the wine these measures organized and funded by the douro region wine cluster involve key players of the cluster particularly in the implementation of the climevinesafe projects directed at short-term measures to mitigate the effect of climate change and also to support the modeling the evolution of wine quality in the dwr project most importantly the cluster s action plan has numerous flagship projects that are focused on developing strategies aimed at reducing the vulnerability of the wine sector by increasing adaptive capacity to achieve these goals numerous convergent adaption activities are being implemented in the region including the study of more efficient use of water by the plants creation of vineyard mapping zoning tools at regional and property scales encouragement of integrated sustainability of viticulture production rationalization of the cultivation of hillside vineyards the study of the behavior of different varieties and rootstocks and last but not least preservation of the genetic biodiversity of the viticultural heritage originating in portugal the board of advid july 2012 1

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executive summary it is evident from the history of growing winegrapes worldwide that they are a climatically sensitive crop whereby quality production is achieved across a fairly narrow geographic range in addition winegrapes are grown largely in mid-latitude regions that are prone to high climatic variability that drive relatively large vintage differences in quality and productivity furthermore historic trends and future projections in climate parameters for wine regions has shown that changes have occurred and are likely to continue in the future this research provides an assessment of numerous aspects of climate in one of the world s most historic wine regions ­ the douro valley of portugal ­ with the goal of documenting and examining the historic current and future climatic conditions of the region while there is a general understanding of the climate of the douro wine region a comprehensive high quality long term station data set for the region has been limited over both space and time therefore this climate assessment utilizes the best available data that are of three main types 1 historic climate normals 2 weather stations within the douro wine region and 3 spatial climate data for observed and future projections of climate in the region furthermore the assessment includes an examination of the relationships between the large-scale regional circulation controls and climate variability in the douro wine region updated spatial climate data for 1950-2000 reveals similar climate conditions to the 1931-1960 climate normal over the douro wine region for growing season average temperatures the region averages 17.8°c and is spatially classed as 65 a warm climate type 24 an intermediate climate type and nearly 10 a hot climate type on the gst index observed trends in the region were examined both for individual stations and spatially over the entire region differences between the 1931-1960 and 1950-2000 data reveal that the later period was warmer by an average of 0.9°c for annual temperatures over the region with the growing season and winter being 1.2°c and 0.4°c warmer respectively examining three long-term stations in the region shows greater warming in minimum compared to maximum temperatures with rates ranging from 1.2°c to 3.6°c during the time period results from an analysis of extreme events for the three stations reveals significant changes for both maximum and minimum temperature extremes with overall warmer nights warmer days a general decline in the diurnal temperature range a higher number heat stress events some evidence for longer warm spells and a clear reduction in cold spell durations future climate conditions in the douro wine region were examined using ipcc sres projections from the hadcm3 model for three greenhouse gas emission scenarios b2 a1b and a2 and three future time slices 2020 2050 and 2080 average annual temperatures are projected to warm for all emission scenarios and for each time slice projections range from 0.5-1.4°c by 2020 1.4-3.3°c by 2050 and 2.1-5.1°c by 2080 for gst the region is projected to change from a largely warm climate suitability 65 of the area in 1950-2000 to increasing area in hot climate suitability by 2020 43 and even very hot climate suitability by 2050 36 by 2080 the spatial pattern of gst is projected to have 19 of the landscape becoming too hot 54 very hot 25 hot and less than 3 cool intermediate or warm the pattern of the changes shows warming increasing most rapidly along the main sections of the river valley then across the douro superior 2

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and by 2080 up in elevation across much of the region precipitation changes for the douro wine region are projected to be fairly low to moderately high depending on the scenario and time period for annual average precipitation the projected changes are near zero to declines as much as 21.6 in the a1b scenario by 2080 the majority of the changes in precipitation are projected to occur during the growing season where decreases from 10-42 are projected by 2080 the future projections for the climate in the region from this assessment are in general agreement with other research for europe the iberian peninsula and portugal wine regions have developed over time to best match their regional environmental conditions allowing for generally consistent ripening of the varieties that were found to be best suited to the conditions while the overall structure of climate in regions drives the suitability and climate variability strongly influences vintage to vintage production and quality variations the projected rate and magnitude of future climate change will likely bring about numerous potential impacts for the wine industry however the douro wine region is rich in landscape and plant characteristics that may help mitigate the deleterious effects of climate change first of all the region s geomorphology and relief contribute to multiple meso and micro-climate situations which may provide spatial adaptation strategies furthermore the landscape provides growers with choices in cultivation techniques to manage the ecophysiological dimension of the environment one characteristic that will be very important is how growers can adapt the landscape and vineyards to help balance global photosynthetic activity of the grapevine and water loss by transpiration a highly significant factor in the management of changes that may be required due to climate change is the genetic heritage of the plant material particularly the varieties and their oenological performance although the general characteristics and aptitude for drought resistance of rootstocks have been studied it is above all the vast heritage of varieties grown in the douro wine region that will provide some of the most useful tools for wine growers both through the different thermal requirements of varieties and the elasticity of their phenological behavior and their different physiological responses by following sustainable approaches and being innovative across the entire production system the douro wine region will undoubtedly reduce its vulnerability and increase its adaptive capacity in the face of a changing climate 3

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introduction climate is a pervasive factor in the success of all agricultural systems influencing whether a crop is suitable to a given region largely controlling crop production and quality and ultimately driving economic sustainability climate s influence on agribusiness is never more evident than with viticulture and wine production where overall it is arguably the most critical aspect in ripening fruit to optimum characteristics to produce a given wine style any assessment of climate for wine production must examine a multitude of factors that operate over many temporal and spatial scales namely climate influences occur at the macroscale synoptic climate to the mesoscale regional climate to the toposcale site climate to the microscale vine row and canopy climate in addition climate influences come from both broad structural conditions and singular weather events manifested through many temperature precipitation and moisture parameters to understand climate s role in growing winegrapes and wine production one must consider 1 the weather and climate structure necessary for optimum quality and production characteristics 2 the climate suitability to different winegrape cultivars 3 the climate s variability in wine producing regions and 4 the influence of climate change on the structure suitability and variability of climate weather and climate s tructure for wine q uality and production worldwide the average climatic conditions of wine regions determine to a large degree the grape cultivars that can be grown there while wine production and quality are chiefly influenced by site-specific factors husbandry decisions and short-term climate variability jones and hellman 2003 individual weather/climate factors affecting grape growth production and wine quality include solar radiation average temperatures temperature extremes including winter freezes and spring and fall frosts and summer heat stress heat accumulation wind and precipitation humidity and soil water balance characteristics while numerous individual and interactive effects between these climate factors can and do occur the most common characterization of mesoclimates in viticultural areas is commonly done as integrated mathematical expressions of temperature that permit the calculation of bioclimatic indices fregoni 2003 jones et al 2010 these indices are typically summed over a period of time important to the vine s growth and production usually the 6 or 7 months of the vine s growth and development cycle the relationships between heat accumulation vine growth and maturation potential was first postulated by a.p de candolle in the nineteenth century where he observed that vine growth started when the mean daily temperature reached 10°c as the various indices were created they were each typically related to the typicity of the wine that can be produced with classes associated with cool climate cultivar wines to warm climate cultivar wines to fortified wines and table grapes various forms of these bioclimatic indices have been created and include the degree-day formulation of the winkler index amerine and winkler 1944 different forms of a heliothermal index branas 1974 and huglin 1978 the quality index of fregoni 2003 a latitude-temperature index jackson and cherry 1988 kenny and shao 1992 and a growing 4

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season average temperature index jones 2006 with each helping to define the suitability of a region to the planting of certain winegrape cultivars given its importance to vine balance fruit quality and yield and disease pressure understanding water relationships in any wine region is very important as such these factors should be assessed from many viewpoints 1 ambient atmospheric moisture 2 local rainfall frequency and timing and 3 soil water holding capacity in addition each of these aspects of water availability can be evaluated in terms of a water balance or budget while ample precipitation during the early vegetative stage is beneficial jones and davis 2000a 2000b during bloom it can reduce or retard flowering during berry growth it can enhance the likelihood of fungal diseases and during maturation it can further fungus maladies yellow and dilute the berries which reduces the sugar and flavour levels and severely limit the yield and quality mullins et al 1992 examination of the world s viticulture regions suggests that there is no upper limit on the amount of precipitation needed for optimum grapevine growth and production gladstones 1992 on the other hand grapevine viability seems to be limited in some hot climates by rainfall amounts less than 500 mm although this can be overcome by regular irrigation if allowed extreme meteorological events such as thunderstorms and hail while generally rare in most viticultural regions are extremely detrimental to the crop both events can severely damage the leaves tendrils and berries during growth and if they occur during maturation can split the grapes causing oxidation premature fermentation and a severe reduction in volume and quality of the yield as an integration of many climate parameters a soil water balance takes into account seasonal variations in temperature precipitation and available soil moisture to give an estimation of water requirements either natural or via irrigation a water balance essentially defines the water need by plants and the atmosphere in any region in most grape growing regions there is a period of soil water surplus from late fall through late spring followed by a period of draw-down of soil moisture through evaporation by the atmosphere and transpiration by plants during the summer and through the early fall when precipitation begins replenishing the soil adequate soil moisture recharge during the spring can drive vine growth and result in more effective bloom and berry set williams 2000 while some soil moisture during the summer growth period can reduce heat stress too high soil moisture can drive too much vegetative growth and lead to inadequate ripening matthews and anderson 1988 along with delayed leaf fall putting the vines at risk of late fall frost/freeze events climate suitability for winegrape cultivars winegrape cultivar suitability to a given region is controlled by the baseline climate historically there have been numerous temperature-based metrics e.g degree-days mean temperature of the warmest month average growing season temperatures etc that have been used for establishing optimum climates for the range of winegrape cultivars gladstones 1992 at the global scale the general bounds on climate suitability for viticulture are found between 1222°c for the growing season in each hemisphere gladstones 2004 jones 2007 figure 1 as seen in figure 1 the 12-22°c climate bounds depict a largely mid-latitude suitability for winegrape 5

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production however many sub-tropical to tropical areas at higher elevations also fall within these climate zones furthermore any general depiction of average temperatures will also include large areas that have not been typically associated with winegrape production this is evident in figure 1 where large areas of eastern europe western asia china the mid-western and eastern united states south-eastern argentina south-eastern south africa and southern australia fall within the 12-22°c thresholds while many of these regions may have the growing season temperatures conducive to growing winegrapes other limiting factors such as winter minimum temperatures spring and fall frosts short growing seasons and water availability would limit much of the areas mapped to the average conditions figure 1 global wine regions and 12-22°c growing season temperature zones apr-oct in the northern hemisphere and oct-apr in the southern hemisphere the wine regions are derived from governmentally defined boundaries e.g american viticultural areas in the united states geographic indicators in australia and brazil and wine of origin wards in south africa or areas under winegrape cultivation identified with remote sensing e.g corine land cover for europe or aerial imagery e.g canada chile argentina and new zealand jones et al 2012 further refining the climate suitability for many of the world s most recognizable cultivars jones 2006 shows that high quality wine production is limited to 13-21°c average growing season temperatures figure 2 the climate-maturity zoning in figure 2 was developed based upon both climate and plant growth for many cultivars grown in cool to hot regions throughout the world s benchmark areas for those winegrapes while many of these cultivars are grown and produce wines outside of their individual bounds depicted in figure 2 these are more bulk wine high yielding for the lower end market and do not typically attain the typicity or quality for those same cultivars in their ideal climate furthermore growing season average temperatures below 13°c are typically limited to hybrids or very early ripening cultivars that do not necessarily have large-scale commercial appeal at the upper limits of climate some production can also be found with growing season average temperatures greater than 21°c although it is mostly limited to fortified wines table grapes and raisons recent research has mapped these climate limits for europe jones et al 2009 australia hall and jones 2010 and the western united states jones et al 2010 detailing the within region climate suitability across the cool intermediate warm and hot climate types this work helps depict the true wine region spatial climate structure instead of 6

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the common practice of using stations which clearly do not properly characterize the climates experienced in the actual vineyard areas figure 2 climate-maturity groupings based on relationships between phenological requirements and growing season average temperatures for high to premium quality wine production in the world s benchmark regions for many of the world s most common cultivars the dashed line at the end of the bars indicates that some adjustments may occur as more data become available but changes of more than 0.2-0.5°c are highly unlikely jones 2006 climate variability in wine regions while the average climate structure in a region determines the broad suitability of winegrape cultivars climate variability influences issues of production and quality risk associated with how equitable the climate is year in year out climate variability in wine regions influences grape and wine production through cold temperature extremes during the winter in some regions frost frequency and severity during the spring and fall high temperature events during the summer extreme rain or hail events and broad spatial and temporal drought conditions climate variability mechanisms that influence wine regions are tied to large scale atmospheric and oceanic interactions that operate at different spatial and temporal scales figure 3 the most prominent of these is the large scale pacific sector el niño-southern oscillation enso glantz 2001 which has broad influences on wine region climates from north america australia and new zealand south africa south america and europe jones et al 2012 however the effects of enso on wine region climate variability varies tremendously in magnitude and is of opposite sign 7

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depending on the location of the wine region and is often coupled with other more influential regional mechanisms jones and goodrich 2008 figure 3 global wine regions climate variability mechanisms and their areas of known influences as described in the text enso ­ el niño southern oscillation pdo ­ pacific decadal oscillation nao ­ north atlantic oscillation iod ­ indian ocean dipole ao ­ arctic oscillation aao ­ antarctic oscillation sst ­ sea surface temperatures the wine regions are as described in figure 1 jones et al 2012 for europe the dominant climate variability mechanism is the north atlantic oscillation nao figure 3 which has a large climatic influence on the north atlantic ocean and surrounding land masses hurrell 2003 the nao is associated with changes in the surface westerlies across the north atlantic due to a large scale seesaw in atmospheric mass between the subtropical high and the polar low the corresponding index that numerically characterizes the nao varies from year to year but also exhibits a tendency to remain in one phase for intervals lasting several years the positive phase of the nao index exhibits a stronger than usual subtropical high pressure center azores high and a deeper than normal icelandic low the increased pressure difference over the north atlantic results in more and stronger winter storms crossing the atlantic ocean on a more northerly track for europe the positive phase results in warmer and wet winters across northern areas and warmer and drier conditions across the mediterranean basin in addition northern canada and greenland experience cold and dry winters while the eastern us experiences mild and wet winter conditions the negative phase of the nao index exhibits a weak subtropical high and a weak icelandic low and the reduced pressure gradient results in fewer and weaker winter storms crossing on a more west-east pathway the result is typically moist air advection and wetter conditions over the mediterranean and cold dry conditions in northern europe the eastern us east coast experiences more cold air outbreaks and hence snowy weather conditions while greenland however will have milder winter temperatures relationships between the nao and winegrape production in europe are mixed with most showing little to no correlation jones 1997 this is likely due to the fact that the nao is largely a wintertime mechanism and its effects diminish over the growing season however there is some evidence that the positive nao phase brings drier growing seasons to the iberian peninsula and the mediterranean that result in lower quality and yield esteves and manso-orgaz 2001 grifoni 8

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et al 2006 for the northern vineyards of europe either phase can be problematic whereby a positive nao brings wetter conditions and greater disease pressure and the negative phase brings greater frost pressure during the spring in addition souriau and yiou 2001 using historical grape harvest dates from north-eastern france and switzerland showed significant correlations between harvest dates and the nao and suggested using the record as an interesting proxy to reconstruct the nao back in time although enso plays a significant role in determining the interannual variability of climate in the lower latitudes its influence on european climate is weak mathieu et al 2004 or hard to differentiate from the effects of the nao rodó and comín 2000 while the impacts of climate change on the average climate of wine regions worldwide is evident see below arguably just as important is how that climate varies increases in climate variability in a given region would bring about greater risk associated with climate extremes which in turn would strain the economic viability of wine production in any region both observations and models indicate that climates experience changes in both the mean and the variability of temperatures in wine regions and elsewhere jones 2007 for example if the change response of a warming climate was only in the mean then there would be less cold weather and more hot and record hot weather on the other hand increases in the temperature variance alone would result in more cold and hot weather and record conditions however evidence points to increases in both the mean and variance which would bring about less change for cold weather events and much more hot weather and record hot weather ipcc 2007 for example schär et al 2004 demonstrate that the european summer climate structure is expected to experience a pronounced increase in year-to-year variability in response to greenhouse-gas forcing while heat waves are caused by entrenched high pressure and blocking patterns such an increase in variability might be able to explain the unusual european summer 2003 and would strongly affect the incidence of heat waves and droughts in the future evidence of changing climate variability in wine regions was also found by jones 2005 and jones et al 2005a where the coefficient of variability in the growing season climates throughout the western us and many other wine regions globally has increased over the last 50 years jones et al 2005a also found that model projections through to 2050 show a continued increase in the coefficient of variability of growing season temperatures in 20 of 27 wine regions globally climate change viticulture and wine from the discussion above on the climate structure suitability and variability associated with regional to global wine production it is clear that viticultural regions are located in relatively narrow geographical and climatic ranges in addition winegrapes have relatively large cultivar differences in climate suitability further limiting some winegrapes to even smaller areas that are appropriate for their cultivation these narrow `niches for optimum quality and production put the cultivation of winegrapes at greater risk from both short-term climate variability and longterm climate changes than more other more broad acre crops jones 2007 in general the overall wine style that a region produces is a result of the baseline climate while climate variability determines vintage quality differences climatic changes which influence both variability and average conditions therefore have the potential to bring about changes in wine 9

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styles jones 2007 our understanding of climate change and the potential impacts on viticulture and wine production has become increasingly important as the earth system undergoes natural cycles and fluctuations and changing levels of greenhouse gases and alterations in earth surface characteristics bring about changes in the earth s radiation budget atmospheric circulation and hydrologic cycle ipcc 2007 observed warming trends over the last hundred years have been found to be asymmetric with respect to seasonal and diurnal cycles with greatest warming occurring during the winter and spring and at night karl et al 1993 easterling et al 2000 the observed trends in temperatures have been related to agricultural production viability by impacting winter hardening potential frost occurrence and growing season lengths carter et al 1991 menzel and fabian 1999 easterling et al 2000 nemani et al 2001 moonen et al 2002 jones 2005 to place viticulture and wine production in the context of climate suitability and the potential impacts from climate change figure 2 provides the framework for examining today s climate-maturity ripening potential for premium quality wine cultivars grown in cool intermediate warm and hot climates jones 2006 for example cabernet sauvignon is grown in regions that span from intermediate to hot climates with growing seasons that range from roughly 16.8-20.2°c e.g bordeaux or napa for cooler climate cultivars such as pinot noir they are typically grown in regions that span from cool to lower intermediate climates with growing seasons that range from roughly 14.0-16.0°c e.g northern oregon or burgundy from the general bounds that cool to hot climate suitability places on high quality wine production it is clear that the impacts of climate change are not likely to be uniform across all cultivars and regions but are more likely to be related to climatic thresholds whereby any continued warming would push a region outside the ability to produce quality wine with existing cultivars for example if a region has an average growing season temperature of 15°c and the climate warms by 1°c then that region is climatically more conducive to ripening some cultivars while potentially less for others if the magnitude of the warming is 2°c or larger then a region may potentially shift into another climate maturity type e.g from intermediate to warm while the range of potential cultivars that a region can ripen will expand in many cases if a region is a hot climate maturity type and warms beyond what is considered viable then grape growing becomes challenging and maybe even impossible furthermore observations and modelling have shown that changes climate have not and will not likely just be manifested in changes in the mean but also in the variance where there are likely to be more extreme heat occurrences but still swings to extremely cold conditions ipcc 2007 therefore even if average climate structure gets better in some regions variability will still be very evident and possibly even more limiting than what is observed today history has shown that winegrape growing regions developed when the climate was most conducive and that shifts in viable wine-producing regions have occurred in the past due to changes in climate making production more difficult or easier le roy ladurie 1971 pfister 1988 gladstones 1992 in europe records of dates of harvest and yield have been kept for nearly a thousand years penning-roswell 1989 le roy ladurie 1971 revealing periods with more beneficial growing season temperatures greater productivity and arguably better quality in some 10

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regions other evidence has shown that vineyards were planted as far north as the coastal zones of the baltic sea and southern england during the medieval little optimum period roughly 9001300 ad when temperatures were up to 1°c warmer gladstones 1992 during the high middle ages 12th and 13th centuries harvesting occurred in early september as compared to early to late october during much of the 20th century pfister 1988 gladstones 1992 however during the 14th century dramatic temperature declines lead to the little ice age extending into the late 19th century which resulted in most of the northern vineyards dying out and growing seasons so short that harvesting grapes in much of the rest of europe was difficult in addition research has used contemporary grape harvest dates from burgundy to reconstruct spring-summer temperatures from 1370 to 2003 and while the results indicate that temperatures as high as those reached in the warm 1990s have occurred several times in the region since 1370 the extremely warm summer of 2003 appears to have been higher than in any other year since 1370 chuine et al 2004 more recent research of the impacts of climate change on wine quality by jones et al 2005a analyzed growing season temperatures in 27 of arguably the best wine producing regions in the world and found that average growing season temperatures warmed 1.3°c over the last 50 years however the warming was not uniform across all regions with greater magnitudes in the western u.s and europe and less warming in chile south africa and australia the greatest warming was seen in the iberian peninsula southern france and parts of washington and california with warming greater than 2.5°c for example jones et al 2005a found that the observed warming during 1950-1999 for the burgundy rhine valley barolo and bordeaux regions ranged from 0.7-1.8°c more regionally specific and temporally resolved analyses concur with the global observations of wine region temperature trends jones and davis 2000a,b jones et al 2005b jones 2007 webb et al 2008 hall and jones 2009 ramos et al 2008 overall during the last 30-70 years many of the world s wine regions have experienced a decline in frost frequency shifts in the timing of frosts and warmer growing seasons with greater heat accumulation in north america research has shown significant changes in growing season climates especially in the western u.s for example during 1948-2002 in the main grape growing regions of california oregon and washington growing seasons warmed by 0.9°c driven mostly by changes in minimum temperatures with greater heat accumulation a decline in frost frequency that is most significant in the dormant period and spring earlier last spring frosts later first fall frosts and longer frost-free periods jones 2005 temporal changes for the napa valley since 1930 jones and goodrich 2008 show that heat accumulation is over 350 units higher degree-days in °c units and has been the result of significant warming at night where the minimum temperatures have climbed 3.0°c while daytime temperatures have not changed significantly precipitation amounts and timing are highly variable in the western u.s being more tied to larger scale climate variability mechanisms such as el niño or the pacific decadal oscillation than structural trends jones and goodrich 2008 recent research for europe shows similar results as those found in north america detailed above jones et al 2005b an examination of climate and phenology trends over the last 30-50 years for eleven locations across a range a climate types in europe cool to warm and for 16 cultivars shows that warming occurred across most seasons but is strongest in the spring and summer growing seasons in the wine regions 11

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