Geological and solar climates: Their causes and variations

"Geological and solar climates by Marsden Manson" is a scientific thesis from the late 19th century. It advances a physical explanation for geological climates, especially the Ice Age, arguing that climate history reflects a shift from dominantly internal (earth) heat to dominantly external (solar) heat.

The book contends that when the young Earth’s surface was above the boiling point of water, dense clouds blocked solar radiation and climate depended on internal heat, progressing through broadly uniform torrid, tropical, and temperate eras independent of latitude. As internal heat waned, water’s special properties governed the transition: vapor trapped heat, liquid water’s high specific heat stored it in the oceans, and ice stored cold. When the 32°F isotherm reached land, widespread glaciation followed in all latitudes; only after ocean heat was exhausted did the clouds clear, letting solar energy establish modern latitudinal belts and seasons. The thesis critiques orbital and other external explanations as insufficient, interprets geological evidence (fossils, moraines, sea-level shifts) through this framework, notes local exceptions from volcanic heat, and argues that the postglacial world has been slowly warming due to atmospheric heat trapping, with natural limits set by clouds and the cold reservoir of the deep oceans, while drawing parallels with planets like Jupiter and Mars.