How does the Atlantic Ocean affect Rio de Janeiro's climate?

The Atlantic Ocean plays a significant role in shaping the climate of Rio de Janeiro through several mechanisms:

• Temperature Regulation: Along the coast, breezes blowing alternately onshore and offshore help modify local temperatures. Additionally, the city’s warmth is influenced by the warm ocean currents that bathe the Brazilian coastline.12
• Precipitation Patterns: The ocean is a primary source of humidity for the region. Coastal mountains act as a barrier to humid winds blowing in from the Atlantic, forcing the air upward and resulting in higher rainfall in those mountainous areas. For instance, the urban district of Jardim Botânico records the highest rainfall rates in the city because the nearby coastal mountains trap these humid Atlantic winds.1

Overall, while Rio de Janeiro maintains a generally tropical, hot, and humid climate, its proximity to the ocean is a defining factor in its daily weather and temperature variations.1