Along most of the Atlantic coast, tides reach their maximum height twice each day. The Gulf of Mexico has only one high and low tide each day. Some places in the gulf have tidal ranges of only a few inches or centimeters. Tides are also small in the Mediterranean. A wide variety of plant and animal life thrives in the Atlantic Ocean.
Animals live throughout the Atlantic.
The surface waters of the continental shelf support one-celled plantlike organisms called phytoplankton . These organisms are a major food for marine life. During winter months, surface waters are mixed by strong winds to greater depths. This process increases nutrient concentrations in the upper waters. When spring begins to warm the surface waters, the ocean experiences the year's largest growth of phytoplankton.