4.0 Waves, tides and currents

DEMOWhat happens when you blow across the

surface of the water? Make a sketchKnow what happens when the cork is added,

does it move across the pan?Why or why not

What is a wave?Transfer of energy (through any material)Most water waves are caused by windWaves crashing into the shoreline can cause

changesLarge waves erode, small waves deposit sandThis is one reason why some lakes have

restrictions on the size of motorboats allowed in the lake

Regional ClimatesRain- occurs more around big bodies of water

as they heat up faster and cause convection currents (think of wearing a black shirt and how fast it heats up)

Thunderstorms- caused by unstable atmospheric conditions where warm, moist air rises but doesn’t cool

Ocean currentsWater move because of currents

Caused by Wind Temperature differences Salinity differences Earth’s rotation

Surface Currents:Caused by wind and prevailing winds (always

blow in the same direction)Convection Currents:

Water is heating differentially (ie equators get more heat than poles) causing warm water to rise

Bill Nye