The development of the field of geophysics is shown through the most frequent words in AGU journal article titles. Early on, the most frequent scientific words in titles were on Earth's magnetism and the effect that the sun, Earth's core, and Earth's atmosphere had on Earth's magnetism. After the 1940s, the most frequent words in titles expanded to include hydrology, water resources, oceans, and climate. The field of geophysics, as seen through the most frequent words, was also influenced by technological advances and sociopolitical events.