Earth’s changing climate is not just causing increasingly punishing droughts, intense wildfires, and extreme weather, it could disrupt the world’s beer supply by as much as 16%. Now, California scientists are brewing up solutions to the dilemma. In Oakland’s Fruitvale district during Oktoberfest, Morgan Cox brews and serves up all kinds of craft beers. On this day, he is making a batch of his Kolsch-style Town Beer. … This batch uses 20 bags of malted barley, fresh water, yeast, and just the right amount of hops, the flowering part of the Humulus lupulus plant that gives beer its bitter taste and aroma.