McKnight's Physical Geography: A Landscape Appreciation by Hess and Tasa
Understanding Earth by Grotzinger and Jordan
Undergraduate
The Solid Earth: An Introduction to Global Geophysics by Fowler
Planetary Surface Processes by Melosh
Atmospheric Science: An Introductory Survey by Wallace and Hobbs
Atmosphere, Ocean and Climate Dynamics: An Introductory Text by Marshall and Plumb
Geodynamics by Turcotte and Schubert
Atmospheric Chemistry and Physics: From Air Pollution to Climate Change by Seinfeld and Pandis (Prerequisites: thermodynamics, transport phenomena/[fluid mechanics and/or heat and mass transfer], and differential equations)