National Geographic: California's current drought is not the state's driest spell on record in terms of total precipitation. If the state feels this drought as a particularly severe one, says Peter Gleick, the blame may fall partly on humans. "The severity of the drought has been compounded by poor planning, poor management, and population growth putting pressure on already overcommitted resources," says Gleick, president of the Oakland, California-based Pacific Institute, a nonprofit that conducts interdisciplinary...