Bay

A bay is a coastal body of water connected to a larger sea or ocean that forms a curved, recessed shoreline, with land surrounding the water on three sides. The waters within a bay are often calmer and warmer than the open coast, and bays vary widely in size, depth, and openness. Some bays are large enough to host major harbors, while others are small indentations along a coast. Examples include the Bay of Bengal, San Francisco Bay, and the Bay of Biscay.

Formation and characteristics: Bays form through a range of geological and hydrological processes, including coastal erosion of softer rocks, differential land movement, sediment deposition that creates peninsulas and promontories, and sea-level changes that flood river valleys or coastal basins. Some bays are estuarine, containing brackish water where freshwater mixes with seawater, while others are more seawater-dominated. The mouth of a bay, where it opens to the sea, and the shape of its coastline influence tidal patterns, currents, and sedimentation.

Ecology and use: The sheltered waters of bays support diverse habitats, such as seagrass beds, mangroves, and estuarine zones that serve as nurseries for fish and invertebrates. Bays are frequently important for human activity, providing harbors, commercial and recreational fishing grounds, shipping routes, and tourism. They can be sensitive to pollution, sedimentation, and coastal development, affecting water quality and ecosystem health.

Notable examples and etymology: Notable bays include the Bay of Bengal, San Francisco Bay, Bay of Biscay, and Hudson Bay. The term bay derives from Old French baie, meaning an opening or inlet.