Beerpocalypse shows climate change is real

Quenching your thirst with an icy cold beer during a heatwave is likely to become more difficult – and expensive, research reveals.

The global beer supply could drop by as much as 16% due to damaged crops of key ingredient barley in years of heatwaves and droughts, according to a paper published in the journal Nature Plants.

“That’s comparable to all beer consumption in the US,” says researcher Xie Wei of the China Centre for Agricultural Policy at Peking University in Beijing, who took part in the work.

Using daily weather information from 1981 to 2010, Wei and colleagues determined the thresholds for 100-year global droughts and heatwaves, and combined this with a global economic model, crop information, and a range of future climate scenarios.

They found that as the average global land surface temperatures increased, there was a steady increase in both the frequency and magnitude of coinciding extreme drought and heat events during barley-growing seasons.

Judging by volume consumed, beer is the world’s most popular tipple. But since barley is also used in animal feed and human food products such as bread, declining crops might be prioritised for products other than ‘luxury’ goods such as ale and lager.

“Concurrent extremes of drought and heat can be anticipated to cause both substantial decreases in beer consumption and increases in beer price,” Wei says.

This will have varying economic impacts in different countries, but under the most severe climate scenario, average beer prices would double. In Ireland, one of the worst hit nations, the scenario could raise beer prices by between 43 and 338% by 2099.

Although it differs according to brewery approaches, beer production — from watering the crops used through to brewing and bottling — uses a lot of water (although its water footprint is still smaller than that of other products such as chocolate, beef or wine).

For example, in a 2010 estimate, the brewing company SABMiller’s South African operations used 155 litres of water for every litre of beer produced; in Peru the ration was 61 to one.

If the availability of fresh water declines, the situation could be even more dire, since the study didn’t forecast the impact of decreasing fresh water availability on barley yields.

“Our results reflect impacts of extreme events as though they happened in today’s world,” Wei says.

“We acknowledge that our methodological approach has some important limitations, including the fact that our estimates of impact are based on the current agricultural practices. As a first step, we seek to isolate the effects of extreme climatic events holding all other conditions constant.

“However, it is a common consensus that the reduction in irrigation water will negatively affect the yields of many crops, especially of those grown in arid areas.”

Research is increasingly examining the impacts of climate change on staple crops such as wheat, soybean and rice. But the vulnerability of beer supply to extreme weather events hadn’t been studied until now.

“Although some attention has been paid to the potential impacts of climate change on luxury crops such as wine and coffee, the impacts on beer have not been carefully evaluated,” Wei says.

Wei hopes the research will encourage some beer-loving individuals to take notice of climate change.

“Our results might attract further attention from societies, nations and of course from the beer-loving individuals at the helm on climate change effects,” he explains.

“Seeing that climate change is affecting our lives in more ways than we imagined before, they might start to think of ways to strengthen global efforts on emissions reduction.”

Compared to some of the direr predictions for our future lives in a hotter planet, beer may seem an insignificant casualty. However, the authors highlight the cross-cultural appreciation for beer, and the fact that for many people it has an important place in social gatherings — and has done so for centuries.

“A sufficient beer supply may help with the stability of entertainment and communication in society,” Wei says.