Climate Change in Wine Industry
Meltdown or the implications of climate change for the wine industry
The greatest threat facing our planet today is climate change or global warming. Climate change is a global issue whose causes and consequences require action at local, national and global levels. As the atmosphere and oceans warm, climate change will bring uncertainty and threats to the agriculture sector, to the economy and almost every activity of the human kind. Just as nuclear Armageddon would have resulted from human failures, global warming is the product of the activities and decisions of humankind.
According to the Intergovernmental Panel on Climate Change (2001), scientists have ascertained that global warming is under way, and they believe that climate change is very likely happening now. It causes increased frequency of severe weather events like floods and droughts, the spread of pathogens to new areas, adverse changes in agricultural yields, increased human mortality from heat and cold, coastal erosion and damage from the rise in sea level, melting glaciers, and a host of other troubles (IPCC, 2001). These problems will harm the poorest countries and peoples the most due to their vulnerable locations and limited resources, which make it difficult or impossible for them to adapt (IPCC, 2001).
Climate Change Research and Projection
Climate change refers to the variation in the Earth’s climate or in regional climates overtime (). It describes changes in the variability or average state of the atmosphere or average weather over time scales ranging from decades to millions of years. These changes may come from processes internal to earth, be driven by external forces or be caused by human activities. In the context of environmental policy, climate change is define as the ongoing changes in modern climate, including the rise in the average surface temperature known as global warming.
(1995) concluded that human activities are changing the atmospheric concentrations and distribution of greenhouse gases and aerosols. These changes can produce a radiative forcing, that is, a change in the energy available to the climate system by changing either the reflection or absorption of solar radiation, or the emission and absorption of terrestrial radiation. He addressed climate change as any change in climate over time whether due to natural variability or as a result of human activity.
In addition, (1986) concluded that the addition of carbon dioxide in the atmosphere is not the only influence of mankind in the climate but also that there are other infrared-absorbing trace gases that can cause a greenhouse effect, such as the chlorofluoromethanes, nitrous oxide, and methane.
Climate change generally is caused by the increased of carbon dioxide and other polluting gases in the atmosphere. Figure 1 shows the process by which gases trap heat by forming a blanket around the Earth like the glass of a greenhouse. Once released the greenhouse gases stay in the atmosphere for many years. As they build up, the planet's temperature rises. Greenhouse gases are released by burning fossil fuels such as coal, oil and gas and by cutting down forests.
A string of recent research findings points to a high probability of serious consequences of climate change if we remain complacent.
For example, NASA and other scientists have observed rapid recession of Arctic sea ice and several research groups have also documented rapid melting of permafrost in the northern hemisphere (2006). These reduce the albedo, or reflectivity of the surface, as bright snow is replaced by darker vegetation and soil, and this, in turn, leads to more global warming, an early positive feedback that makes things progressively worse.
Among the most affected regions of climate change are those at the high latitudes (2001). The extreme forecast is that fundamental ecosystems will be modified as the continuous and discontinuous permafrost boundaries move northwards by several hundred kilometers, along with attendant shifts in the tree-line. Moisture loss, resulting from the melting of the currently impermeable permafrost layer underlying northern wetlands, would be exacerbated by increased evaporation resulting in the rapid loss of wetlands, the foundation of complex ecological systems. Sea-ice cover will shrink, substantially affecting the habitat of marine species such as ringed and bearded seals, sea-lions and walruses which require ice for breeding. It has been estimated that fresh-water fish will migrate pole ward by 150km for every 1°C increase in temperature, possibly displacing current resident species ( 2001).
In addition, according to (2006), observations now indicate that the world's forests, long regarded as important sinks for carbon dioxide could be transformed into treacherous sources of greenhouse gases as global warming proceeds, a disturbing turnaround and, again, one that means global warming will feed itself.
(2005) states that a number of scientists have recently observed vegetation and soils acting as sources rather than sinks and this could mean an earlier-than-expected positive, that is undesirable, feedback in the terrestrial carbon cycle.
Heat waves and other extreme events are predicted to become more frequent with climate change. News at Nature reported that a team of European scientists had found that the stifling 2003 heat wave in Europe caused the continent's grasslands and forests to release massive amounts of carbon dioxide into the atmosphere. The carbon dioxide released as a result of the heat wave was equivalent to the amount of carbon stored in plants over the previous four years of normal growth.
In addition, global warming is expected to lead to a more vigorous hydrological cycle, including more total rainfall and more frequent high intensity rainfall events (IPCC, 1995). These rainfall changes, along with expected changes in temperature, solar radiation, and atmospheric carbon dioxide concentrations, will have significant impacts on soil erosion rates. The processes involved in the impact of climate change on soil erosion by water are complex, involving changes in rainfall amounts and intensities, number of days of precipitation, ratio of rain to snow, plant biomass production, plant residue decomposition rates, soil microbial activity, evapotranspiration rates, and shifts in land use necessary to accommodate a new climatic regime. Soil erosion rates may be expected to change in response to changes in climate for a variety of reasons, the most direct of which is the change in the erosive power of rainfall ( 2001; 2002). A second dominant pathway of influence by climate change on erosion rates is through changes in plant biomass. The mechanisms by which climate changes affect biomass, and by which biomass changes impact runoff and erosion, are complex (2002).
Climate change also affects the sea water level. One of the more-certain predictions associated with global climate warming and the melting of polar ice caps is a rise in sea level ( 1989). Sea level rise for the last century is estimated at 4-6 inches, in part due to thermal expansion of water. Most estimates project a rise of about three feet over the next one hundred years, corresponding to 10-15 inches for each one-degree rise in temperature. Such a rise in sea level can be expected to have serious consequences, especially if at least some preventive measures are not implemented. The major impacts are permanent inundation, beach erosion, increased flooding and saltwater intrusion. Continual development along coastal regions will not only increase the probability and extent of flood damage, but will result in the destruction of some of the natural barriers that help to mitigate these effects.
The globally averaged surface temperature is projected to increase by 1.4 to 5.8°C over the period 1990 to 2100 (IPCC, 2001). In addition, global average water vapor concentration and precipitation are projected to increase during the 21st century. By the second half of the 21st century, it is likely that precipitation will have increased over northern mid- to high-latitudes and Antarctica in winter. At low latitudes there are both regional increases and decreases over land areas. Larger year to year variations in precipitation are very likely over most areas where an increase in mean precipitation is projected.
Moreover, Northern Hemisphere snow cover and sea-ice extent are projected to decrease further. Glaciers and icecaps are projected to continue their widespread retreat during the 21st century. The Antarctic ice sheet is likely to gain mass because of greater precipitation, while the Greenland ice sheet is likely to lose mass because the increase in runoff will exceed the precipitation increase. Further, global mean sea level is projected to rise by 0.09 to 0.88 metres between 1990 and 2100.
Emissions of long-lived greenhouse gases have a lasting effect on atmospheric composition, radiative forcing and climate. After greenhouse gas concentrations have stabilized, global average surface temperatures would rise at a rate of only a few tenths of a degree per century rather than several degrees per century as projected for the 21st century without stabilization.
Impact on the wine industry
The hotter days and warmer nights that global warming may bring could compel most premium wine grape growers to lower their quality. Premium wine grapes are usually defined as such because they are used to make wine. Lower-quality grapes end up in jug or fortified wine, as table grapes and as raisins. Growing premium wine grapes requires the right climate: hot during the day and cool at night. Temperature extremes can ruin otherwise good wine grapes.
However, some level of climate change is nothing new to wine-growing regions, according to Greg climate scientist at Southern Oregon University and another study author ( 2006). According to winemaker at Bogle Vineyards in Clarksburg, lengthening the growing season is a good thing for wine grapes, because the best spend a long time slowly maturing on the vine and this gives the grapes enough time to develop the correct balance of flavor and sugar ( 2006). However, according to , of Shenandoah Vineyards in Amador County, when temperatures get too high, about 95 to 100 degrees, the grapes pretty much shut down. If you get to about 100 degrees, the vine shuts down, and if you get to 100 day after day, the leaves start burning ( 2006).
According to (2004), growing season temperatures have increased for most of the world's high quality wine regions over the last 50 years by an average of 2°C. In tandem with this rise in temperatures, the quality of vintages has also improved. There is a significant relationship between the vintage ratings and monthly average growing season temperatures in most regions. Jones accepts that there is a chance that the rise in vintage quality might not just be because of the temperature increases, but points out that his data show that between 10% and 62% of vintage quality can be explained by growing season temperature variability, with the greatest effects seen in cool climate regions such as the Mosel.
In the prediction of wine regions can expect an average growing season temperature increase of 2.04°C by 2049, on top of the 2°C rise of the last 50 years. The largest predicted change was for southern Portugal which is 2.85°C and the lowest was for South Africa which is 0.88°C (2004).
According to it would appear that the currently cool climate regions would benefit the most (2004). If the climate warms as the models predict, then these regions will be better able to ripen the fruit, and may even be able to consider other varieties that could not ripen there today.
However, global warming is detrimental to some of the warmest wine regions, including most of the vineyard areas in California. For, according to many of the warm-to-hot regions the negative impacts are already being felt. In hot regions, grapes ripen to a 'sugar ripe' condition, but lack flavors that can take time to develop (2004). Other regions, somewhat in between cool and hot growing climates, will likely have to consider other varieties that will produce better in a new climate regime. For example, in California's Napa and Sonoma valleys, the climate has become so warm that ripening fruit is not an issue but retaining acidity and developing flavor have become increasingly difficult in the warmer conditions (2004). This issue could become very critical in already warm areas like Chianti, Barolo, Rioja, southern France, the Hunter Valley, parts of Chile and the Central Valley of California.
In addition, negative effects of increased temperatures could include harvest periods being brought forward into the warmest parts of the year, reduced water availability and increased pest and disease burden.
Moreover, one of the common predictions of climate models also has implications for wine with rising temperatures come an increased frequency of extreme weather events and a rising unpredictability of climates. Winegrowers don't want unusual weather; understandably, they like things to be predictable and stable, because large fluctuations will almost always be detrimental for vintage quality. Even if growing season temperatures are very good, a vintage can be easily ruined by extended rain during harvesting, or hailstorms, or a late snap of frost in May.
Response of the wine industry
In response to climate change, there will be a local adaptation by each environment, a possibility for planting new varieties in regions not previously suitable. Varieties only grown 500km south of a region may be possibly planted further north.
According to (2004), the observed warming of the past 50 years appears to have mostly benefited the quality of wine grown worldwide. However, the average predicted warming in the next 50 years has numerous potential impacts on the wine industry including changes in grapevine phenological timing, disruption of balanced composition in grapes and wine, alterations in varieties grown and regional wine styles, and spatial changes in viable grape-growing regions.
Potentially even more important is that climate change, through its direct impact on grape and wine production, has the ability to indirectly bring about cultural change by altering long-held regional identities.
The wine industry likely can adapt to the possible changes in climate, but not without help. Today many of the Old World wine regions in Europe have stringent standards by which varieties, yields, growing and winemaking techniques, and wine styles are regulated to assure quality and maintain identities (2004).
For example, the summer heat wave of 2003 in Europe produced very early harvests and some challenging growing conditions that without irrigation resulted in lower yields and out-of-balance flavors (2005). Although New World wine regions have fewer governmental constraints, growers and winemakers worldwide will need the freedom to adapt to the potential changes in climate in both the short and long term.
Climate change affects almost every aspect of living of the human kind. It affects the agriculture industry with the unpredictable change in the weather. It also affects the temperature of the globe which causes the permafrost to melt down increasing the sea water level and loss of inhabitants of some animals. Global warming is threatening to the future of the humankind. With the wine industry it is particularly important to be able to predict the climate because wine grape are particularly affected with changing weather. Extreme weather conditions affect the quality of the grapes. Vintage quality of grapes is easily ruined even with extended rainfall, or when temperature reached 95°F the grapevine will shut down.
Figure 1. Heat from the Sun (a) is trapped by the gases in our atmosphere (b)
Source: Friends of the Earth ()
Table 1. Predicted temperature rises for selected wine regions over the next 50 years
PREDICTED TEMPERATURE RISE
WINE REGION FOR THE PERIOD 2000-2049 ([degrees]C)
Central Washington 2.27
Eastern Washington 2.81
Northern Oregon 1.56
Southern Oregon 2.35
Northern California 2.16
Southern California 1.38
Northern Portugal 2.42
Southern Portugal 2.85
Rhine Valley 1.51
Mosel Valley 1.51
Northern Rhone 2.26
Southern Rhone 2.26
Loire Valley 2.14
Burgundy--Cote d'Or 2.09
Hunter Valley 1.78
Margaret Valley 2.04
Barossa Valley 2.01
South Africa 0.88