Vulnerabilities - Spain
Changes until now
During the period 1958–2005 the thermal conditions for the development and maturation of grapes in north-western Spain have improved (1). In this area, trends in spring and summer temperatures, and in spring rainfalls are positive (2). This could be of benefit to the development of the vineyards during the budbreak and bloom stages (1). For the autumn, no significant trends in temperature are seen, but a slight positive trend in rainfall is observed (2).
Projection for the first half of the 21st century
Premium-quality wine areas in Europe are at risk due to climate change. In the north of Spain climate change probably results in an overall shift towards higher yields of lower-quality fruit, resulting in lower-quality and lower-priced wines. In Central and Southern Spain more irrigation will be needed to compensate for heat stress increase and to avoid quality losses. This will increase already existing conflicts in water allocation (8).
To what extent climate change affects high-quality wine production in Spain varies between different parts of Spain. As a result, options to adapt to climate change also vary. This was concluded from an assessment of the impact of climate change in 2031 – 2050 compared with the reference period 1981–2000. This assessment was based on calculations with a number of climate models (both global and regional) and a moderate scenario of climate change (the so-called A1B scenario). In this assessment Spain was divided into four major agro-climatic regions (8):
This is a relatively cool and wet region with large Atlantic influence, where very low local temperatures limit potential maturity and sugar content; this region includes commercially interesting white wines made with single varieties.
In the northwest, areas at higher altitudes surrounding the Pyrenees in the north and the Iberian mountains in the south may become suitable for viticulture. On the one hand, reduction of frost occurrence may favor optimal ripening. On the other, higher night temperatures during ripening period might reduce wine color and aromas potential. The need for irrigation may increase in the dryer regions. Other adaptation measures that may be necessary are the introduction of later varieties or rootstocks changes.
This is a temperate Mediterranean climate region, mainly along the Ebro valley; this region produces many of the premium-quality wines (e.g. Rioja). In the northeast, viticulture may become possible in areas that are too cool at present. A reduction of precipitation, indicated by some of the models, might increase wine quality and reduce humidity-nurtured diseases such as mildew. Only in some cases, irrigation might be necessary.
Central Spain has a very pronounced dry and hot season; the region produces major exports and some new premium wines.
In Central Spain, conditions may improve for some grape varieties as a result of frost reduction and better ripening, whereas growing seasons may become too warm for other varieties that loose color and aromas potential. Irrigation is already practiced in 40% of the vineyards of Central Spain and may need to be expanded, thus increasing already existing conflicts in water allocation.
This is the very hot and dry southern Mediterranean area, that produces fortified wines.
In the southern Mediterranean area projected warming trends show potential increments of heat stress and quality losses. Water availability will probably become the most limiting factor in the future as water needs are expected to rise and more irrigation will be needed to prevent severe drought and heat stress.
Projection for the second half of the 21st century
Central and southern Spain
For the second half this century an intense increase in accumulated heat in central and southern Spain is projected, which would negatively impact wine quality in these regions. Particularly in southern Spain, the excessive warming projected for the end of the twenty-first century would impede the production of high-quality wine and would hinder grapevine growth (6). This is in contrast to the north and northwest, where thermal conditions would become more favorable. This was concluded from climate change projections for the period 2061 - 2091 compared with 1961 – 1991, under a moderate scenario of climate change (the so-called A1B scenario) and based on 4 regional climate models (6).
According to climate projections for the period 2061–2091 based on four regional climate models and the A1B emissions scenario, grape production and wine qualitywill benefit from temperature increase and rainfall decrease during the growing season (1,6). The election of the grape varieties and wine styles may change in the future. The possibility of attacks by pests such as the mildew will reduce and thus allow the introduction of new varieties of grape in this region (1). Beyond 2100 these benefits might vanish, however (6). Also, and already this century, a shift in the mean climate conditions may be accompanied by an increase in inter-annual variability (7), which would negatively affect winegrowing in years experiencing large climate anomalies.
In rain fed vineyards in the northeast of Spain, temperature and precipitation changes under a moderate and high-end scenario of climate change (the so-called RCP4.5 and RCP8.5 scenarios) are projected to advance dates of budbreak, bloom, veraison and harvest in the growing cycle of white grapes. Depending on grape variety, these stages may advance up to 10-16 days for 2050 and up to 12-20 days for 2070 under the moderate (RCP4.5) scenario. Under the high-end (RCP8.5) scenario, the advance by 2070 could be up to 23-28 days (11).
In addition, a reduction of available water, due to higher evapotranspiration and higher water loss by runoff, may increase the advance of some phenological stages, in particular veraison. The advances in phenology and the shortening of the growing cycle produce ripening under warmer conditions, which may affect grape quality (11).
Erosion vineyard soils
Does climate change affect the erosion of vineyard soils in the Mediterranean? Recent results for a Spanish study area (a basin about 40 km northwest of Barcelona) show that year-to-year variability in observed erosion rates is too high to come up with a clear answer to this question (3). The study area is representative of erosion rates in vineyards in the Mediterranean area ((Portugal, Spain, France, Italy and Greece) (4). The results do not allow accurate predictions of the influence of climate change on soil erosion in the Mediterranean area. It is an important issue, however: estimations carried out in the study area indicate that soil losses in vineyards represent about 9 % of income from grape sales (5).
Longer dry periods and greater rainfall concentration in a reduced number of events of higher intensity may affect the risk of erosion. More extensive droughts can remove the protective vegetation cover, leaving the soil more exposed to erosion, while more intensive rains can detach more soil and produce a severe increase in erosion rates. Thus, it may be expected that changes in temperature (through evaporation rates) and precipitation affect erosion rates. Therefore, projections of temperature and precipitation have been made for 2020, 2050 and 2080 under a scenario of relatively strong climate change (the high end A2 scenario). Climate data for the period 2000–2012 and detailed soil and land use maps were used as input data (3).
Soil loss depends on the balance of precipitation and evapotranspiration. For the 2020 scenario, precipitation increase does not balance the increase in evapotranspiration, and a decrease in runoff and soil loss is projected. For the 2050 and 2080 scenarios, however, precipitation increase offsets evapotranspiration increase: soil loss may be up to 5.6 % greater in 2050 and 12 % greater in 2080 than at present. The impact of climate change may be much larger, however, when for the same rainfall distribution rainfall intensity changes: an increase of 10-20 % in rainfall intensity increased soil loss by between 8 and 10.3 % for the 2020 scenario, and by up to 57 % for the 2050 scenario (3).
In Spain, climate change adaptation measures are particularly needed in the southern part of the country. This may include changing the grape varieties, applying irrigation, or displacing the growing areas to higher elevations, characterized by colder climate conditions (6).
A consistent result in all wine regions of Spain is the need for additional water for irrigation in order to ensure stable production targets and minimize the risk of drought damage. It is highly questionable whether this can be achieved since current water policy in Europe limits additional irrigation infrastructure (9).
The references below are cited in full in a separate map 'References'. Please click here if you are looking for the full references for Spain.
- Lorenzo et al. (2013)
- Gomez-Gesteira et al. (2011), in: Lorenzo et al. (2013)
- Ramos et al. (2015)
- Kosmas et al. (1997); Ruiz Colmenero et al. (2013); Bienes et al. (2012); Ramos and Martínez-Casasnovas (2010); Maetens et al. (2012); Paroissien et al. (2010), all in: Ramos et al. (2015)
- Martínez-Casasnovas and Ramos (2006), in: Ramos et al. (2015)
- Lorenzo et al. (2016)
- Schär et al. (2004); Rodríguez-Puebla et al. (2010); Fraga et al. (2013), all in: Lorenzo et al. (2016)
- Resco et al. (2016)
- Iglesias and Garrote (2015), in: Resco et al. (2016)
- White et al. (2006), in: Resco et al. (2016)
- Ramos et al. (2017)