Ocean Currents and Tides Flashcards

Grade 6 · Science · Flashcards

Review key vocabulary about ocean currents, tidal forces, and their effects on Earth.

Flashcards

Ocean current: A continuous, directed flow of ocean water; can be surface or deep depending on driving force.
Surface current: Wind-driven ocean current in the upper layers of the ocean.
Thermohaline circulation: Deep ocean circulation driven by density differences from temperature (thermo) and salinity (haline).
Density: Mass per unit volume; cold, salty water is denser and sinks; warm, fresh water is less dense and rises.
Coriolis effect: Deflection of moving objects by Earth's rotation; right in Northern Hemisphere, left in Southern.
Gyre: A large circular system of ocean surface currents created by wind and the Coriolis effect.
Gulf Stream: A powerful warm-water surface current flowing north from the Gulf of Mexico along the US East Coast and to Europe.
Tide: The daily rise and fall of sea level due primarily to the Moon's gravitational pull.
High tide: When the ocean level is at its highest point along a shore.
Low tide: When the ocean level is at its lowest point along a shore.
Spring tide: Strong tide during new or full moon when Sun, Moon, and Earth align; largest tidal range.
Neap tide: Weaker tide during quarter moon when the Sun and Moon are at 90°; smallest tidal range.
Tidal range: The difference in water level between high tide and low tide.
Salinity: The concentration of dissolved salts in ocean water; about 3.5% on average.