Suess, Hans E.

Hans E. Suess.

Hans E. Suess (1909-1993), an American chemist who developed an improved method of carbon-14 dating, which he used to document the profound effect that the combustion of fossil fuels had had on the Earth’s stocks and flows of carbon (1955). Fossil fuels are so ancient that they contain no carbon-14 (¹⁴C), so when combusted, the carbon dioxide (CO₂) they release dilutes the ¹⁴C content of both atmosphere and plants. This dilution is now known as the "Suess effect", and it unequivocally proved that the increase in atmospheric CO₂ was due to the combustion of fossil fuels. In a seminal paper published in 1957 with Roger Revelle, Suess argued that humankind was performing "a great geophysical experiment", calling on the scientific community to monitor changes in the carbon dioxide content of waters and the atmosphere, as well as production rates of plants and animals. He also used ¹⁴C to establish the chronology of the end of the last Ice Age in the northern hemisphere, substantially reducing the traditional estimates. With Harold Urey, he made a fundamental contribution to cosmochemistry with a description of the abundances of elements based on meteorite data (1956).

Further Reading

• Heinrich Waenke and James R. Arnold. 2006. Biographical Memoirs: Hans E. Suess. The National Academies Press.