Atmospheric sciences is an umbrella term for the study of the atmosphere, its processes, the effects other systems have on the atmosphere, and the effects of the atmosphere on these other systems.
Meteorology includes atmospheric chemistry and atmospheric physics with a major focus on weather forecasting.
Climatology is the study of atmospheric changes (both long and short-term) that define average climates and their change over time, due to both natural and anthropogenic climate variability. Climatology considers the past and can help predict future climate change.
Aeronomy is the study of the upper layers of the atmosphere, where dissociation and ionization are important.
Scope: Meteorologists are best-known for forecasting the weather. Many radio and television weather forecasters are professional meteorologists, while others are merely reporters with no formal meteorological training. The American Meteorological Society and National Weather Association issue "Seals of Approval" to weather broadcasters who meet certain requirements.
Indian Institute of Tropical Meteorology - Pune functioned under Ministry of Earth Sciences (MoES), Doing Basic Research on the Ocean-Atmosphere Climate System required for improvement of Weather and Climate Forecasts.