Average barley yield shocks during extreme events years. Graphic: Xie, et al., 2018 / Nature Plants

IRVINE, California, 15 October 2018 (UCI) – On top of rising sea levels, stronger hurricanes, and worsening wildfires, scientists project that human-caused climate change will result in one of the most dire consequences imaginable: a disruption in the global beer supply.In a study published today in Nature Plants, researchers from the University of California, Irvine and other institutions report that concurrent droughts and heat waves, exacerbated by anthropogenic global warming, will lead to sharp declines in crop yields of barley, beer’s main ingredient.The economic models used in the paper demonstrated strong potential for price surges in some beer-loving countries, and whether or not people get to enjoy a frosty mug of suds will likely depend on their willingness to pay.“The world is facing many life-threatening impacts of climate change, so people having to spend a bit more to drink beer may seem trivial by comparison,” said co-author Steven Davis, UCI associate professor of Earth system science. “But there is definitely a cross-cultural appeal to beer, and not having a cool pint at the end of an increasingly common hot day just adds insult to injury.”He said the research team modeled scenarios based on current and expected future levels of fossil fuel burning and carbon dioxide emissions. In the worst case, parts of the world where barley is grown – including the northern Great Plains, Canadian prairies, Europe, Australia, and the Asian steppe – were projected to experience more frequent concurrent droughts and heat waves, causing declines in crop yields of 3 to 17 percent.“Current levels of fossil fuel consumption and CO2 pollution – business as usual – will result in this worst-case scenario, with more weather extremes negatively impacting the world’s beer basket,” said co-author Nathan Mueller, UCI assistant professor of Earth system science. “Our study showed that even modest warming will lead to increases in drought and excessive heat events in barley-growing areas.”Only 17 percent of the globe’s barley is used in brewing; in fact, most is harvested as feed for livestock. This sets up a conflict in the decades to come: Will producers prioritize hungry animals over thirsty humans? Inputting a decline in barley supply into their computable general equilibrium model, the researchers consistently found that the ratio of the grain going to beer brewing decreased even more. So, in a word: yes.

Barley consumption by country and globally under future climate change. Graphic: Xie, et al., 2018 / Nature Plants

The study further outlines how different regions of the world will be affected, determining that prices will go up the most in such wealthy, beer-loving countries as Belgium, Canada, Denmark, and Poland. For example, Davis said, during drought years, residents of Ireland could need to bring the equivalent of an extra $20 to the store to buy a six-pack. But he noted that some people in these nations will be willing to absorb the higher cost.Beer consumption is predicted to go down in poorer countries, such as China, and Davis joked that even the United States might see a drop-off in keg stands and beer pong tournaments in the future.“Our results show that in the most severe climate events, the supply of beer could decline by about 16 percent in years when droughts and heat waves strike,” he said. “That’s comparable to all beer consumption in the U.S. Future climate and pricing conditions could put beer out of reach for hundreds of millions of people around the world.”Scientists from China’s Peking University, the Chinese Academy of Agricultural Sciences, Mexico’s International Maize and Wheat Improvement Center, and the U.K.’s University of East Anglia also contributed to the study, which received support from the National Natural Science Foundation of China and the U.S. National Science Foundation.

Global warming will have us crying in what’s left of our beerExtreme events severity and frequency in barley-growing regions and during the barley-growing season under future climate change. Graphic: Xie, et al., 2018 / Nature Plants

ABSTRACT: Beer is the most popular alcoholic beverage in the world by volume consumed, and yields of its main ingredient, barley, decline sharply in periods of extreme drought and heat. Although the frequency and severity of drought and heat extremes increase substantially in range of future climate scenarios by five Earth System Models, the vulnerability of beer supply to such extremes has never been assessed. We couple a process-based crop model (decision support system for agrotechnology transfer) and a global economic model (Global Trade Analysis Project model) to evaluate the effects of concurrent drought and heat extremes projected under a range of future climate scenarios. We find that these extreme events may cause substantial decreases in barley yields worldwide. Average yield losses range from 3% to 17% depending on the severity of the conditions. Decreases in the global supply of barley lead to proportionally larger decreases in barley used to make beer and ultimately result in dramatic regional decreases in beer consumption (for example, −32% in Argentina) and increases in beer prices (for example, +193% in Ireland). Although not the most concerning impact of future climate change, climate-related weather extremes may threaten the availability and economic accessibility of beer.

Decreases in global beer supply due to extreme drought and heat