Will great wine vintages become rarer?
Northwest China is becoming warmer and wetter, but is this a blessing or a curse for local agriculture?
Many people’s first instinct is that becoming ‘wetter’ is a positive development for the arid inland Northwest—after all, more water should mean more crops can be grown. However, the impact of climate change on agriculture is akin to the butterfly effect: complex and difficult to predict.
Take the wine industry, a key sector in the Northwest, as an example: increased heat and precipitation are altering both the yield and quality of wine grapes. In the realm of agriculture, wine grapes are often likened to the ‘canary in the coal mine’. In the past, miners would take canaries underground because the birds are far more sensitive to toxic gases than humans; if the canary died, the miners knew the air was dangerous and they had to evacuate. Similarly, wine is exceptionally sensitive to climatic conditions, and its prosperity or decline reflects local climatic shifts. This is why the vintage is so critical when choosing a wine; only the right balance of sunlight, heat, and moisture can produce a bottle of superior quality.
Thus, the story of wine grapes provides a glimpse into the unprecedented challenges currently facing agriculture in the Northwest.
The trend towards becoming “wetter”, however, only began in the mid-1980s. This climatic signal was first captured in 2002 by Shi Yafeng, an academician of the Chinese Academy of Sciences, who proposed that against the backdrop of global warming, most of Northwest China would see a trend of “warming and wetting”.
In the twenty-plus years since, scientists have continued to observe increased precipitation in the Northwest, with rare extreme rainfall events in recent years drawing public attention. In July 2021, torrential rains caused flooding in the Taklamakan Desert, covering an area of over 300 square kilometres.
A recent report by the international environmental organisation Greenpeace, titled *The Temperature of Civilisation: A Systematic Assessment of the Impact of Climate Change on the Ecology, Industry and Cultural Heritage of Northwest China*, also suggests that rising temperatures and shifting precipitation patterns caused by climate change are increasing the frequency and intensity of extreme weather. This poses severe challenges to the stability of ecosystems, agricultural sustainability, and the preservation of tangible cultural heritage in the Northwest.
I. Warming: A Double-Edged Sword
Ms Yin explains that grapes are a crop particularly sensitive to climatic conditions; during several key growth stages, any meteorological disaster can have a massive impact on yield, or even lead to a total crop failure. Facing unpredictable weather, their most critical work now is early prevention of crop disasters and post-disaster recovery.
For example, in late April 2020, Zhangye suffered four consecutive days of low temperatures, dropping to between -6 and -8 degrees Celsius. This not only prevented the grapes from fruiting that year but also meant the vines took two to three years to recover, with economic losses reaching tens of millions of yuan.
Against the broader backdrop of “warming and wetting” in the Northwest, such disasters are likely to become more frequent. Li Chao, the author of the aforementioned Greenpeace report, says that when she visited the vineyards in Zhangye for research in April 2022, the locals were on high alert, bracing for the potential arrival of late frosts. Wood and cow dung were piled in the vineyards; if temperatures dropped too low, fires would be lit to raise the temperature through smoke.
“But on the very night we were filming, it snowed in Zhangye city, and fires were lit in the vineyards outside town. A vineyard technician told me that there have been several late frosts causing significant losses in recent years. After managing vineyards for so long, he now feels he’s ‘forgetting how to grow’ them,” she said.
Since the 1980s, warming temperatures have led to higher accumulated heat and longer growing seasons, causing the suitable cultivation areas for wine grapes in China to expand steadily northward. While this is a boon for the colder northern regions where grapes previously could not be grown, it creates management headaches for traditional producing regions. Firstly, during the critical summer growth phase, higher temperatures cause grapes to ripen earlier and accumulate more sugar. This alters the flavour profile of the wine: alcohol levels rise, while aroma and acidity decrease. Greenpeace found that over the last 60 years, the increase in effective accumulated temperature during the growing season has become a key factor limiting the quality of grapes in Northwest Jiuquan and parts of Longnan. A study from the Ningxia Key Laboratory of Meteorological Disaster Prevention and Mitigation found that the increase in average temperature during the hottest month in the Yinchuan area is also detrimental to the quality of wine grapes.
Furthermore, warm winters are a double-edged sword. While average temperatures in the Northwest have risen significantly since the 1960s, leading to warmer winters, this also adversely affects wine grapes. Firstly, it helps pests survive the winter; secondly, warm winters cause vines to bud earlier, leaving them more vulnerable to late spring frosts.
Conversely, despite these warmer winters, low-temperature frost damage continues to threaten wine grapes.
The aforementioned late frost disasters in Zhangye have similarly occurred in the Ningxia region on the eastern foothills of the Helan Mountains. In March 2018, daily average temperatures were 5–6°C higher than historical norms, causing winter-dormant grapes buried in the soil to bud prematurely. Consequently, the new shoots were entirely destroyed by successive frosts in early April. In recent years, Ningxia has seen wine grape yields drop by over 40% in years affected by late frosts. Li Yuding, a renowned local viticulture expert, noted in his research that late frost damage has become the most significant meteorological disaster in most northern regions, second only to drought.
Greenpeace has found that since 2000, there has been a leap in the frequency of late frosts in Gansu Province, with an increase in frost occurrence during the budding and flowering periods across most of northern Gansu. The report suggests that the primary cause is the fluctuation in extreme low temperatures. Against the backdrop of global warming, temperature extremes are intensifying—both extreme heat and extreme cold are becoming more pronounced. In other words, hot periods are hotter and cold periods are colder. For instance, between 1961 and 2020, the average extreme low temperature during the wine grape growing season in Gansu Province decreased at a rate of 0.045°C per decade. This downward trend accelerated to 0.14°C per decade between 1991 and 2020, with the decline being even more pronounced during the budding and flowering stages.
II. Becoming Wetter: A Decline in Wine Quality
In a report by *The Intellectual*, Chen Yaning, a researcher at the Xinjiang Institute of Ecology and Geography of the Chinese Academy of Sciences and Director of the State Key Laboratory of Desert Oasis Ecosystems, argues: “Although precipitation in the Northwest has increased, the number of rainy days has not risen significantly. The increase in precipitation is largely due to the heightened intensity of single rainfall events or torrential rain. This increased probability of extreme precipitation actually exacerbates climate disasters, raising the risk of drought and localised flash flooding in the Northwest.”
Furthermore, becoming “wetter” is not necessarily a good thing for traditional wine-grape growing regions. Increased rainfall before harvest can cause the fruit to split, dilute the sugars in the grapes, and make them more susceptible to downy mildew. In recent years, North and Northwest China have experienced rainier summers; for grape growers, there is nothing more heartbreaking than seeing their hard work come to nothing due to prolonged rainy weather just as the harvest season arrives. Taking Yinchuan, a key wine-producing region, as an example: data from 1961 to 2015 shows an increasing trend in both precipitation and the number of rainy days in the month preceding the wine-grape harvest (September), which has a detrimental effect on quality.
It is not just grapes; for crops accustomed to arid climates, increased rainfall often brings unexpected negative consequences. The ‘Zhiliangtian’ ecological farm in Alashan has faced such a dilemma: last summer, after several consecutive days of rain, the difference in humidity and temperature inside and outside the muskmelons grew, causing them to crack. A quarter of the crop could not be harvested, and those that were showed a drop in sweetness.
III. The Climate Dilemma for Wine Grapes: A Global Struggle
*TIME* once reported on the story of Merlot—hailed as the ‘Queen of Red Wines’—which may face extinction in Bordeaux, one of the world’s most famous wine regions. Due to rising temperatures, grapes in Bordeaux have ripened earlier and developed higher sugar content over recent decades, with Merlot being the biggest casualty.
Winemakers are already working to breed new varieties adapted to a warming climate, change planting and irrigation techniques, and even scout for new vineyard sites. In the past, to ensure the unique and pure taste of Bordeaux wines, French authorities only permitted six red and eight white grape varieties to be grown in the designated Bordeaux appellations. However, in 2019, an exception was made to introduce six new varieties to adapt to climate change.
The book *The Earth Doesn’t Care* mentions the issue of pests affecting European wine grapes: global warming has expanded the habitat of the Spotted Wing Drosophila. This pest is now being found in regions that previously experienced harsh winters, threatening not only wine grapes but other types of fruit as well. Scientists believe that as temperatures continue to rise, the pest will spread to even wider areas.
A 2020 study found that if no action is taken, 56% of the world’s existing wine-growing land will disappear if global temperatures rise by 2°C; if they rise by 4°C, this figure will reach 85%. According to the latest IPCC report, global temperatures have already risen by more than 1°C since the Industrial Revolution. The World Meteorological Organization announced that this July was the hottest month ever recorded. Wine, acting as the ‘canary in the coal mine’, is warning us that if temperatures cannot be controlled, the delicacies we have enjoyed in the past may drift further and further away.
Shi Yafeng et al. “Discussion on the Characteristics and Trends of the Transition from Warm and Dry to Warm and Wet Climate in Northwest China.” Quaternary Research 23.2(2003):13.
Wang Jing, et al. “Response of Agricultural Climate Resources for Wine Grapes in the Yinchuan Area on the Eastern Foothills of Helan Mountains to Climate Change.” Chinese Agricultural Resources and Zoning 38.09(2017):122-129.
Li Yuding, et al. “Impacts of Climate Change on Wine Grapes on the Eastern Foothills of Helan Mountains and Countermeasures.” Grapes and Wine .01(2019):38-40+43. doi:10.13414/j.cnki.zwpp.2019.01.009.
Li Yuding, et al. “Reflections on the Sustainable Development of the Wine Grape Planting Industry in Ningxia.” Grapes and Wine .02(2019):99-102. doi:10.13414/j.cnki.zwpp.2019.02.022.
Will Global Warming Turn the Northwest Deserts into Oases?, The Intellectual, https://zhishifenzi.blog.caixin.com/archives/249094
The Challenges Facing an Eco-farm Under the Warming and Wetting of the Northwest, China Dialogue, https://chinadialogue.net/zh/5/99486/
Meet the ‘new’ Bordeaux wine grapes, Decanter,https://www.decanter.com/learn/new-bordeaux-grapes-wines-420290/
Morales-Castilla, Ignacio, et al. “Diversity buffers winegrowing regions from climate change losses.” Proceedings of the National Academy of Sciences 117.6 (2020): 2864-2869.
How Climate Change Is Affecting France’s Wine Industry | Time，https://time.com/5777459/france-wine-climate-change/
Editor: Wang Hao