"Under higher-warming climate scenarios, we find 100-year drought and heat events occur every three years, decreasing barley yields by an average 17 percent in those years, and increasing the price of a 6-pack in the U.S. by $1-8. Another way climate change will suck."
The effects described in the report are complex, as the researchers used several forecast tools — one to predict a range of climate scenarios, one for agricultural yields and another to see the economic conditions that would likely result. And as we've seen with the Earth's shifting climate, the predicted effects vary widely from region to region.
Under four different weather scenarios created for the years from 2010 to 2099, the world's barley growers would see "yield losses [that] range from 3 percent to 17 percent depending on the severity of the conditions," according to the study.
Beneath that overall impact, regional differences would be stark.
South America would fare poorly, as would many tropical areas. In China and the U.S., the barley yield is actually predicted to rise — but "not enough to offset the global decrease," the study says.
Climate change could reshape the barley and beer market, the researchers say, depicting a situation in which China — which currently drinks more Budweiser than the U.S. — would scale back its beer consumption.
Whether the best- or worst-case scenario plays out, beer drinkers in Ireland, Canada, Poland and Italy will likely see prices increase the most, according to the report. Beer-loving countries Belgium and the U.K. are also in the top 10.
Even under the two middle-range climate models used in the study, beer consumption is forecast to fall by an average of around 2 billion liters in China alone. The U.S. wouldn't be far behind, with beer consumption projected to fall by an average of around 1.75 billion liters.
The researchers acknowledge that their study has some limitations. For one thing, there's the difficulty of predicting the behavior of beer drinkers, and their shifting tastes. Then there's the possibility that barley farmers might find ways to adapt.
"Our results reflect impacts of extreme events as though they happened in the present day," the study says, adding, "Global population and socioeconomic conditions are also held constant."
The Brewers Association, the U.S. trade group, responded to the study by calling it "largely an academic exercise and not one that brewers or beer lovers should lose any sleep over."
Saying that the beer industry "certainly understands and is already preparing for shifts in climate," BA economist Bart Watson and supply chain expert Chris Swersey write that barley production has always shifted geographically — while production efficiency "continues to grow over time."
Another element to consider, Watson and Swersey say, is the research that's being done to help not only barley, but also hops — another crucial ingredient in beer — withstand high temperatures and drought.
The study's authors call their work a first step in analyzing the long-term impacts for beer drinkers, saying they wanted "to isolate the effects of extreme climatic events holding all other conditions constant."
Of course, there are those among us who could stand to cut back on beer. After all, a recent study in The Lancet medical journal stated, "Our results show that the safest level of drinking is none." But Dabo Guan, one of the study's lead authors who is a professor of climate change economics, noted that beer has been part of human history for thousands of years.
"It may be argued that consuming less beer isn't itself disastrous, and may even have health benefits," Guan said in a statement from the University of East Anglia, where he works. "Nevertheless, there is little doubt that for millions of people around the world, the climate impacts on beer availability and price will add insult to injury."
The research paper has attracted wide attention, as it gives people a very concrete reference point from which to view the concept of climate change. Davis admitted to being unsure of how to view that phenomenon, after the report "garnered considerably more attention than any of my previous work on energy transitions or even air pollution deaths."
But Davis also acknowledged that for him, as it is for many, the beer index is personal. This research, he said, was "born of love and fear."
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