From AMS Glossary
An approach to the study of climate based on physics and mathematics rather than the more empirical and descriptive methods of traditional climatology.
This term was coined by H. Lettau (1969) to describe his one-dimensional representation of climate based on the energy and water balances at the surface.
Lettau, H., and K. Lettau 1969. Shortwave radiation climatonomy. Tellus. 21. 208–222.