Humans were impacting global drought as far back as the early 20th century, according to a new study from NASA’s Goddard Instutitue for Space Studies. The study, published in the journal Nature, compared predicted and real-world soil moisture data to look for human influences on global drought patterns. Climate models predict that a human “fingerprint” – a global pattern of regional drying and wetting characteristic of the climate response to greenhouse gases – should be visible early in the 190