Jerry Mitrovica has been overturning accepted wisdom for decades. A solid Earth geophysicist at Harvard, he studies the internal structure and processes of the Earth, which has implications for fields from climatology to the timing of human migration and even to the search for life on other planets. Early in his career he and colleagues showed that Earth's tectonic plates not only move from side to side, creating continental drift, but also up and down. By refocusing attention from the horizontal of modern Earth science to the vertical, he helped to found what he has nicknamed postmodern geophysics. Recently Mitrovica has revived and reinvigorated longstanding insights into factors that cause huge geographic variation in sea level, with important implications for the study of climate change today on glaciers and ice sheets.