Matching Pairs Waves, Currents & TidesOnline version 5th Grade Science Unit by Julie Copeland 1 What are tides? 2 What are estuaries? 3 Trough 4 What causes surface currents? 5 Wave 6 How often do tides occur? 7 What are inlets? 8 What is a barrier island? 9 Current 10 Crest 11 Wind The highest part of a wave The area where a river meets the ocean The movement of Earth and the force and direction of wind. Pieces of land surrounded by water on all sides that protect the mainland. The regular rise and fall of the waters in oceans and seas. Water-filled spaces between barrier islands The cause of most waves to form Flowing streams of water that move along a curved path through the ocean in a specific direction The lowest part of the wave This occurs about twice a day. The repeated movement of water up and down