Meteorologist and weather forecaster. He began his career in 1884 as an assistant a the University of Michigan's Astronomical Observatory. In 1885 he was appointed assistant at Harvard University's Astronomical Observatory, and from 1886 to 1891 served as an observer at Harvard's Blue Hill Meteorological Observatory. From 1891 to 1893 he worked as a local forecast offical with the United States Weather Bureau. In 1894 Clayton returned to Blue Hill Meteorological Observatory, where he served as a meteorologist until 1909. Clayton became Chief of the forecast division of the Argentine Weather Service in 1914. While in Argentina, Clayton pursued research on a system of weather forecasting based on solar heat changes and began corresponding with Charles G. Abbot of the Smithsonian Institution, who was also conducting reseach on solar variation. From 1923 to 1936 he conducted research in cooperation with the Smithsonian on the effect of solar variation on world weather patterns. Clayton directed a private weather forecasting service and served as a consulting meteorologist for business organizations from 1920 until his death.