Anticyclone

Part of speech: noun

Definitions

1. A large region of high atmospheric pressure leads to descending air that diverges, often causing fair weather conditions and influencing local meteorological phenomena
2. This atmospheric system involves a central area of elevated pressure with outwardly flowing winds, contributing to notable weather stability and prevention of cloud formation
3. A weather system characterized by a center of high pressure that promotes downward airflow, resulting in clear skies and generally stable weather patterns

Etymology: Sir Francis Galton, the Victorian polymath better known for his work on heredity and fingerprints, is the man who coined this term in the 1860s. He needed a name for the weather system that was the opposite of the cyclone, a storm-like rotating mass of low pressure that had only recently been described as a single phenomenon. Rather than inventing a fresh word, he took the existing "cyclone" and attached the Greek prefix "anti-", meaning "against" or "opposite". The result is a neat piece of scientific shorthand. A cyclone draws air inward and upward around a low-pressure core, while an anticyclone does the reverse: air sinks and spreads outward from a high-pressure centre. That descending air warms as it falls, which suppresses cloud formation and is why these systems so often bring calm, clear skies.

Synonyms: high pressure system, weather system, anti-cyclonic system, stable air mass, aerial dome

Antonyms: cyclone, low pressure system, depression, storm, tropical cyclone