At its essence, beer is made of hops, grain, water, and yeast. Climate change is already affecting how the sudsy brew is produced.
Hops affect beer’s aroma, flavor, and bitterness. According to the USDA, 73% of the hops in the U.S. are grown in Washington State — primarily the Yakima Valley on the eastern slopes of the Cascades — with the rest generally grown in Oregon and Idaho.
Very hot conditions negatively impact the more aromatic varieties of hops. And while 2015 was very hot in Washington State, irrigation was sufficient to keep yields high. But most of the irrigation water for this area comes from the annual melting of the Cascades snowpack and there are concerns about the availability of sufficient water for beer production as the Earth heats up. Warmer winters lead to more precipitation falling as rain versus snow, while warmer springs melt that snowpack earlier in the season, leaving less available water during the heat of the summer and into the early fall harvest. This will make irrigation more difficult, and hops may become more dependent on groundwater supplies. Because of a higher mineral content, use of groundwater will negatively affect the beer’s taste.
The grain used in fermentation, usually malted barley, gives beer its color. Most U.S. barley is produced in the Upper Midwest and Northern Rockies, but as the climate has warmed, higher cash crops like soybeans and corn have been migrating into regions traditionally used for barley. More troubling, cereal crops like barley are highly susceptible to droughts and heatwaves.
Acknowledging climate change, several breweries have signed a Brewery Climate Declaration. In this document, the brewers indicate their commitment to using renewable energy, capturing methane from wastewater treatment, cutting transportation costs, and using/distributing spent grain (grain that has already been stripped of sugars during the brewing process, but still contains protein and fiber) for agriculture. All in the hopes that your St. Patrick’s Day brew will be green in more ways than one.