Climatology is the scientific study of Earth's climate, typically defined as weather conditions averaged over a long-term period. It is a subfield of physical geography and atmospheric sciences concerned with both the description of climate and the analysis of the causes of climatic differences and changes and their practical consequences. It is one of the fundamental fields for the undergraduate students in geography and earth sciences to understand the fundamental concept of climatology and its interactions with other components (hydrology, morphology, ecology, and geology) in physical geography and earth system sciences.