Climatology is the study of long-term weather patterns and their effects on the environment. It is a branch of physical geography that focuses on the analysis of climate systems, including the atmosphere, hydrosphere, biosphere, and lithosphere. Climatologists use data from meteorological instruments, satellite imagery, and other sources to study the Earth's climate and its changes over time. They also investigate the causes and effects of climate change, such as global warming, and develop strategies to mitigate its impacts.