Understanding Currents Current Video Hook Understanding Currents Bill Nye- Currents Video Understanding Currents What do currents do? Move water around the Earth Distribute heat and nutrients What two types of currents are there? Surface and deep ocean currents What happens every 3 to 7 years when winds do not blow strong enough? El Nino Understanding Tides Bay of Fundy Clip Understanding Currents How often do the tides occur? Every day What causes tides? The gravity from the sun and moon Tides can be used to generate Electricity Intertidal Zone Untamed Science- Intertidal Zone Untamed Science- Intertidal Zone Intertidal Zone What is the intertidal zone? Area between highest high tide (spring) and lowest low tide (neap) 2 Types of Intertidal Zones Based on substrate: Rocky Intertidal Western Coast of US, Eastern Canada and New England Sandy Intertidal Eastern and Gulf Coasts of US Abiotic Factors Exposure to air Threat of high temp. Higher organisms live in intertidal, more time exposed Desiccation drying out Clam up Run and hide Wave shock Bigger problem along rocky shores Hits headland the hardest Wave Refraction Other Challenges Feeding Restrictions Filter feeders cannot eat when tide is out Predators More difficult to hide when tide is out Salinity fluctuations Decreases with rain Increases with evaporation Intertidal Zone More on the Intertidal Zone More on the Intertidal Zone