Download presentation
Presentation is loading. Please wait.
Published byKathlyn Benson Modified over 8 years ago
1
Waves, Tides, and Currents MOTION IN THE OCEAN
2
Write the following under your WAVES Column Write everything that is in Red
3
Waves A disturbance which moves through or over the surface of a fluid Mostly caused by winds (Also earthquakes, volcanoes, gravitational pull) (Also earthquakes, volcanoes, gravitational pull) Form of great energy
4
Wave Characteristics Parts of a Wave Crest = high point Crest = high point Trough = low point Trough = low point Height = vertical distance from crest to trough Height = vertical distance from crest to trough Wavelength = Horizontal distance between crest to crest or trough to trough Wavelength = Horizontal distance between crest to crest or trough to trough
5
Wave frequency : the number of crests that pass a certain point in an amount of time.
6
Size of Wind Generated Waves Depends on 2 things : Wind Speed Wind Speed Wind Duration (length of time wind blows) Wind Duration (length of time wind blows)
7
Importance of Waves Shaping Coastlines Erode cliffs Erode cliffs Grind rock into sand Grind rock into sand Ecology Returns O 2 to water Returns O 2 to water Stir up food for filter feeders Stir up food for filter feeders
8
Types of Waves CHOP – Short period (back bays) SWELL – Long period (boat rolls; seasickness) SWASH – water up beach BACKWASH – back down
9
Caused by undersea quake or volcano Wavelength = ~150 mi. Wave height = 6ft – 1mile Can NOT perceive in boat Speed > 500 mph Slows down to ~25 mph at shore; water builds up to ~65+ ft TSUNAMI “TIDAL WAVE”
10
Tsunami Waves
11
Creation of a Tsunami
12
Write the following under your TIDES Column Write everything that is in Red
13
Tides The rhythmic rise and fall of the ocean’s water High tide = rising, incoming tide, flow Low tide = lowering, outgoing tide, ebb Slack tide = vertical movement stops
14
Tides are very long, slow waves They have a wave period of 12 hours 25 min They have a wave period of 12 hours 25 min Tidal day is 24 hours 50 min Tidal day is 24 hours 50 min NJ has 2 high and 2 low tides daily NJ has 2 high and 2 low tides daily
15
1. Gravitational pull of sun & moon on Earth What Causes Tides? Moon closer, therefore greater effect Like magnet, pulls water away from surface = TIDAL BULGE
16
Types of Tides 2x’s/month 2x’s/month Spring Tide - Moon and sun are in direct line with one another - Results in unusually high tidal range -Tidal Range = vertical distance between high & low tides
17
Neap Tide sun and moon are at right angles sun and moon are at right angles Pulls cancel each other out – causes a weak pull Pulls cancel each other out – causes a weak pull unusually low tidal range unusually low tidal range 2 x’s / month 2 x’s / month
18
Spring vs. Neap Tides
19
Importance of Tides Expose & submerge orgs Circulate water in bays & estuaries Trigger spawning (grunion, horseshoe crab) Circulates food, wastes, etc
20
Write the following under your CURRENTS Column Write everything that is in Red
21
Currents What are currents? - “Rivers” of circulating water Causes - Wind - Rotating Earth - Density Changes
23
Surface Ocean Currents Created by wind
24
Coriolis Effect - Northern Hemisphere – clockwise; Right - Southern Hemisphere – counterclockwise; Left
25
Gulf Stream - Brings warm water from equator north along east coast of North America -Located in the North Atlantic Ocean
26
MIGRATION NAVIGATION WEATHER
27
RIP CURRENT - Caused by converging longshore currents - Very dangerous ; Red Flag - DO NOT fight rip current; swim parallel to shore to get out of channel
29
Deep Ocean Currents Separated from surface currents by the density of the water Density = mass volume volume Flow beneath surface; cross equator Move North to South
30
Importance Of Deep Currents Upwelling Upwelling Brings deep water to surf.Brings deep water to surf. Circulates nutrients upCirculates nutrients up Moves plankton & larvaeMoves plankton & larvae
Similar presentations
© 2024 SlidePlayer.com Inc.
All rights reserved.