Which French physicist strengthened Fourier's greenhouse-effect argument in 1827 and 1838?

Claude Pouillet strengthened Fourier’s greenhouse-effect argument in 1827 and 1838. The French physicist developed a more quantitative account of how the atmosphere affects Earth’s surface temperature.

Joseph Fourier had argued in the 1820s that Earth was warmer than it would be if it received sunlight without an atmosphere. Pouillet extended that line of thought through studies of solar heat, atmospheric absorption, and terrestrial temperature. His 1827 textbook, Éléments de physique expérimentale et de météorologie, and his 1838 memoir on solar heat presented important steps in that development.

Pouillet built and used a pyrheliometer, an instrument for measuring solar radiation. Between 1837 and 1838, he made one of the first quantitative estimates of the solar constant, obtaining about 1,228 watts per square metre—close to the modern value, though based on an imperfect method.

Pouillet also suggested that water vapour and carbon dioxide could absorb infrared radiation and help warm Earth. His work was not the complete modern theory, and later researchers such as John Tyndall and Svante Arrhenius refined the physics. Still, Pouillet provided a crucial bridge between Fourier’s concept and quantitative climate science.