The time in this zone is determined by the mean solar time of the of the Greenwich Observatory. Geographic Coverage Atlantic Time is primarily used in the following regions:
Puerto Rico, the U.S. Virgin Islands, Bermuda, the Dominican Republic, and several other island nations. atlantic time
is a time zone observed in parts of North America, South America, and the Caribbean. It is defined by two primary offsets from Coordinated Universal Time (UTC): Atlantic Standard Time (AST): UTC−04:00. The time in this zone is determined by