2 STANDARDExplain that a large portion of Earth’s surface is water, consisting of oceans, rivers, lakes, groundwater, and ice.
3 Lesson 10 A Wet PlanetEQ: How is Earth’s water distributed among saltwater and freshwater sources?
4 How is Earth’s water distributed among saltwater and freshwater? Some people call Earth the “blue planet” because over 70% of Earth’s surface is covered with water.Most of Earth’s freshwater is found in the polar ice caps near the North and South Poles.From largest to smallest, the amounts of water on Earth are salt water (97%), solid fresh water (2%), liquid fresh water (1%).
5 Salt Water Most of the water on Earth is found in Earth’s oceans Oceans contain salt water.The salinity, or salt concentration, averages about 3.5%, or 35 grams of salt per 1 kg of water.In order of size from largest to smallest, Earth’s oceans are the Pacific, Atlantic, and Indian Oceans.
6 Fresh WaterMost of the Earth’s freshwater is located in the polar caps (ice).A glacier is a very slow moving river of ice.Underground water, lakes, rivers, and glaciers hold the rest of Earth’s surface freshwater.The largest portion of the Earth’s useable freshwater is trapped between underground layers of rock. This trapped freshwater is called groundwater.
7 Quick Check About how much of Earth’s surface is covered by water?
8 Quick CheckFrom the largest to smallest, the amounts of water on Earth areliquid fresh water, solid fresh water, salt water.B. salt water, solid fresh water, liquid fresh water.C. salt water, liquid fresh water, groundwater.D. groundwater, salt water, solid fresh water.
9 Quick Check A glacier is A. a river of liquid water. B. an ice cap. C. a solid lake.D. a slow river of ice.
10 Lesson 25 Sun, Wind, and Water EQ: How does a drop of water move through the water cycle?
11 Wind Earth receives heat energy from the sun through Radiation. Radiation is the movement of energy through empty space.Air at different places on Earth heats up unevenly. The uneven heating up of Earth’s air is what produces wind.Cool air moves toward warmer air. Warm air moves away from cooler air. Moving air is wind.
12 Water Very little water is ever lost on Earth The sun is the source of energy that drives the water cycle.Energy from the sun causes the water particles to move faster and escape into the air as water vapor.
13 WaterWater vapor rises into the air and cools down. The water molecules move slower and come closer together, or condense. This is called condensation.Condensation forms clouds and precipitation such as rain, sleet, hail, and snow.The precipitation falls to the ground and gathers there in puddles, ponds, rivers, lakes, and oceans. (Accumulation)Some water seeps into the ground and collects there. This underground water is called groundwater. (runoff)
14 Water Some groundwater finds its way into oceans. Water on the surface is warmed again by the sun and will evaporate. So will water in the soil.Water vapor also enters the air from plants. This is called transpiration.This keeps the water cycle going.
15 Quick CheckWhat is the source of energy that produces winds and causes evaporation?A. lightningB. Earth’s rotationC. the moonD. the sun
16 Quick CheckHeating liquid water produces A. snow. B. rain. C. water vapor. D. groundwater.
17 Quick Check The sun’s energy reaches Earth through A. evaporation. B. condensation.C. radiation.D. wind.
18 Quick Check What process produces rain? A. condensation B. evaporation C. warmingD. solidification
19 Quick Check Water vapor is a A. liquid B. solid C. gas D. form of energy
20 Quick Check The cooling of water vapor leads FIRST to A. cloud formation.B. evaporation.C. formation of groundwater.D. precipitation.
21 Quick Check What process produces a cloud? Evaporation Condensation Radiationwarming
22 Lesson 11 The World’s Oceans EQ: How does the composition and topography of earth’s oceans vary by location?
23 Location of the World’s Oceans The Pacific Ocean is the largest ocean. It is bordered by North America, South America, Asia, Australia, and AntarcticaThe Atlantic is the second largest ocean. It is bordered by N. America, S. America, Africa, Europe, and Antarctica.The third largest ocean is the Indian Ocean. It lies between the countries of India, Pakistan, Australia, and the continents of Africa and Antarctica.
24 Composition of the World’s Oceans The main substance dissolved in ocean water is sodium chloride (NaCl) or table salt.Other dissolved solid substances are sulfate, magnesium, calcium, and potassium.Solid substances dissolved in sea water come from rivers, streams, rocks from the shore, volcanoes and underwater hot springs.The concentration of all the dissolved substances in sea water is about 3.5%.
25 Composition of the World’s Oceans The oceans also hold dissolved gases, such as oxygen and carbon dioxide.Marine life such as fish need dissolved oxygen in sea water to live.Sea plants such as seaweeds need carbon dioxide to survive. They get it from the dissolved carbon dioxide in sea water.
26 Topography of the World’s Ocean Floor Oceanographers have mapped the ocean floors by using special equipment.Echo sounding, (pings), measure the time it takes a pulse of sound to go from the ship to the ocean floor and echo back to the ship.The speed of sound in sea water averages about 1520 m per second.
27 Quick Check Which continents border the Atlantic Ocean? A. North America, South America, Asia, AustraliaB. Asia, Australia, AfricaC. North America, South America, Europe, AfricaD. South America, Europe, Asia, Australia
28 Quick CheckWhich substance do fish need to live and take in from water that you take in from air?A. saltB. oxygenC. carbon dioxideD. water
29 Quick CheckPings from an echo sounder aboard a ship make a round trip in 8 seconds. How far beneath the ship is the ocean floor?A. 2,920 metersB. 6,080 metersC. 11,680 metersD. 23,360 meters
30 Quick CheckWhich shows the order of Earth’s three major oceans from largest to smallest?A. Pacific, Atlantic, IndianB. Atlantic, Pacific, IndianC. Indian, Atlantic, PacificD. Atlantic, Indian, Pacific
31 Quick CheckIf you were to walk along the ocean bottom from a beach, which of the following features would you reach after the continental shelf?A. the abyssal plainB. a seamountC. the mid-ocean ridgeD. the continental slope
32 Quick CheckAbout how deep is the deepest pat of the world’s oceans? A meters B meters C. 11,000 meters D. 14,000 meters
34 The Water Cycle Section 11-1 How is Earth’s water distributed among saltwater and freshwater resources?How does Earth’s water move through the water cycle?Explain the steps of the water cycle.How do people and other living things use water?
35 Based on the Pie Chart, what does the blue or green represent on the graph?
36 What Does This Mean? Earth’s Water Total Water on Earth 2% is frozen in glaciers and ice capsONLY 1% IS AVAILABE FOR HUMAN CONSUMPTION.Saltwater97%Freshwater3%
37 Water on Earth Most of Earth’s water is saltwater (97%) Most saltwater is found in the oceansOnly about 3% of water is freshwaterAll living things must share about 1% of the total amount of water on Earth
38 Water on the Earth Almost all the water on Earth is salt water (97%). Of the three percent that is fresh water, 76% is frozen in the ice caps at the poles.
39 Distribution of Water on Earth Saltwater oceans and (salt) lakes (97%)Freshwater (3%)Of the total Freshwater on Earth:76% of freshwater is ice12% of freshwater is Shallow Groundwater11% of freshwater is Deep Groundwater0.34% of freshwater is found in Lakes and Rivers0.037% of freshwater is Water VaporAll living things share less than 1% of total water on Earth!
41 The Water Cycle 1Water is naturally recycled through a process known as the water cycleWater moves from bodies of water, land, and living things from Earth’s surface, up to the atmosphere and then back to Earth’s surface.Steps for the water cycle are: evaporation, condensation, and precipitation
42 The Water CycleThirstin's Water Cycle Animation
43 The Water CycleContinuous process by which water moves through the living and nonliving parts of the environment.The source of energy that drives the water cycle is the SUN!
44 EvaporationEvaporation – the process by which liquid water on the surface change to a gasMost evaporated water comes from oceans, and most precipitation falls back into the oceans.The salt does not get enough energy to become a gas, so it stays behind.
45 Cloud FormationClouds formation – water vapor loses energy, cools down, condenses into liquid water droplets, droplets clump together around tiny dust particles, forming clouds
47 The Water Cycle 3Water vapor also enters the air from plants. This is called transpiration.Condensation – process by which gas molecules change into a liquid. This process forms cloudsPrecipitation – process in which clouds become too heavy to hold the water droplets, and the droplets fall to the Earth’s surface as rain, sleet, snow or hail
50 How Do People Use Water?Humans use water for household purposes, agriculture, industry, transportation, and recreation.Agriculture/Irrigation is the process of supplying water to areas for growing cropsIndustry – to make products, cool off machinesTransportation – travel upon the oceans, lakes and riversRecreation – exercise and sports
51 Water and Living Things Water is important for living things to grow, reproduce and carry on other essential processes.Photosynthesis – plants use water, carbon dioxide and sunlight to make their own foodHabitat – place an organism lives and provides the things it needs to survive
52 Water Cycle Vocabulary Evaporation: the process of energy changing liquid water into water vapor (a gas) and rising in the airCondensation: the cooling of water vapor, which changes it back into a liquidPrecipitation: the release of condensed water that the air cannot hold any longer. Precipitation occurs in the form of rain, hail, sleet, or snow
53 Transpiration: : the process by which plants lose water out of their leaves and into the air Collection- When water collects together to form a body of water. Lakes, puddles, oceans, etc.
54 Water Cycle Vocabulary Clouds: condensed water madeup of water droplets andtiny dust particlesGroundwater: water that collect above the bedrock layer and moves like an underground river
55 Percolation/infiltration: the downward movement of absorbed precipitation by the soil, which eventually collects as groundwaterRunoff: water that flows over the surface of land
56 Answers to The Water Cycle A = precipitation B = condensation C = evaporationThe sunTranspiration is the process in which the leaves of plants give off waterWater vapor cools, cold air causes water to condense, water droplets clump together around tiny dust particles, causing clouds to formThe oceans are where most precipitation falls and where most evaporation takes placeGroundwaterirrigation
57 Quick CheckMore than 97% of Earth’s total water supply is found in A. ice sheets. B. groundwater. C. the atmosphere. D. the oceans.
58 Quick CheckThe energy the drives the water cycle comes from A. the sun. B. the Earth. C. the rain. D. oceans.
59 Quick CheckRain that falls on a steep, paved street during a thunderstorm would most likely be called: A. groundwater. B. runoff. C. a spring. D. a reservoir.
60 Quick CheckMore than two-thirds of Earth’s freshwater is found in A. rivers and streams. B. ponds and lakes. C. glaciers and icebergs. D. wetlands.
61 Quick CheckHow does the water cycle renew Earth’s supply of fresh water? A. evaporation. B. condensation C. the sun D. precipitation
62 Clouds are an example of which stage of the water cycle? Quick CheckClouds are an example of which stage of the water cycle?Condensationevaporationpercolationprecipitation
63 Ocean Water Chemistry How salty is ocean water? (5) How do the conditions in the ocean change with depth? (5)How did the ocean form, and how is it currently divided? (4)Describe one factor that increases the salinity of seawater and one factor that decreases salinity. (4)
64 The Salty Ocean (1)Salinity- the measure of the amount of dissolved salts in a given amount of waterThe average amount of salt in ocean water is about 3.5% or 35 grams of salt per one kilogram (1000 g) of waterOcean water carries many different dissolved saltsSodium Chloride (table salt) is the most abundant salt in the ocean
65 The Salty Ocean (2)The main substance dissolved in ocean water is sodium chloride (NaCl) or table salt.Other dissolved solid substances are sulfate, magnesium, calcium, and potassium.Solid substances dissolved in sea water come from rivers, streams, rocks from the shore, volcanoes and underwater hot springs.The concentration of all the dissolved substances in sea water is about 3.5%.
67 Gases Found in the Oceans The oceans also hold dissolved gases, such as oxygen and carbon dioxide.Marine life such as fish need dissolved oxygen in sea water to live.Most oxygen in oceans come from the atmosphere because it is closer to the surface of the water.Sea plants such as seaweeds need carbon dioxide to survive. They get it from the dissolved carbon dioxide in sea water.
68 The Salty Ocean Temperature decreases in the ocean with depth Pressure increases with depth in the oceanScuba divers are prevented from descending farther than 40 m because of pressureFurther depth will cause the lungs to collapse!
69 How Did the Oceans Form?About 4 billion years ago, the Earth cooled enough for water vapor to condense.The water began to fall as rain.The rain filled the deeper levels of Earth’s surface and the first oceans began to form.
70 Divisions of the Global Oceans Pacific- the largest ocean; getting smallerAtlantic- the second largest; getting largerIndian- third largest;Southern- located along the border of AntarcticaArctic- smallest ocean; most oceanographers consider it as an extension of the Pacific and Atlantic Oceans
71 Location of the World’s Oceans The Pacific Ocean is the largest ocean. It is bordered by North America, South America, Asia, Australia, and AntarcticaThe Atlantic is the second largest ocean. It is bordered by N. America, S. America, Africa, Europe, and Antarctica.The third largest ocean is the Indian Ocean. It lies between the countries of India, Pakistan, Australia, and the continents of Africa and Antarctica.
73 Increasing and Decreasing Salinity Salinity- the measure of the amount of dissolved salts in a given amount of water.Factors increasing salinity include : evaporationfreezingfactors decreasing salinity include precipitationrivers dumping water into oceans
74 Characteristics of Ocean Water Ocean water is saltyChock-full of solidsClimate affects salinityWater movement affects salinityTemperate zonesSurface temperature Changes
75 Ocean Water is SaltyMost of the salt found in oceans is sodium chloride (table salt).Salts have been added to the oceans for billions of years by running waters (rivers, streams) which dissolve various minerals, and then dump the water into the oceans.Also, solid materials come from volcanic eruptions, hot springs, ocean waves crashing against rocks
76 Chock-Full of SolidsSalinity- the measure of the amount of dissolved salts in a given amount of water.Measured in grams (g).1 kg (1000 g) of ocean water carries an average of 35 g of salt (3.5%).During the water cycle, fresh water from the ocean is evaporated leaving only the salts behind.
77 Climate Affects Salinity Some parts of the ocean are saltier than other parts of the ocean.Coastal waters in places with hotter, drier climates have a higher salinity.Coastal waters in places with cooler, more humid climates have a lower salinity.Main reason: evaporationCoastal waters in general have less salinity because more fresh water from rivers run into the oceans in these areas.
78 Water Movement Affects Salinity Some parts of the ocean (bays, seas, gulfs) move less than other parts.Also, some parts of the open ocean that do not have currents run through them can be slow moving.Slower-moving areas of water develop high salinity.
79 Temperate Zones Temperature of ocean water decreases with depth. Water in the ocean is divided into three layers by temperate.Top layer (surface zone)Middle layer (thermocline zone)Bottom layer (deep zone)
80 Temperature ChangesTemperature in the surface zones vary with latitude and the time of the year.Parts of the ocean along the equator are warm because it receives more direct sunlight per year than areas closer to the poles.
81 Answers to Ocean Water Chemistry 9. Ocean water because it contains salt10. Sodium chloride11. Because this is where oceans meet the atmosphere and where algae live12. The pressure of the water13. Submersible14. Salinity15. Water columnSurface to about 200 m17.5°CTransition zoneBottom of surface zone to 1 kmDeep zone3.5°C35g of salt per 1 kg of waterPrecipitation, rivers, evaporation, freezing
82 Quick CheckOcean water is more dense than freshwater at the same temperature because of A. pressure. B. salinity. C. the Coriolis effect. D. upwelling.
83 Quick CheckThe most common substances dissolved in ocean water are A. sodium and chloride. B. potassium and chloride. C. potassium and sodium. D. calcium and chloride.
84 Quick CheckThe concentration of all dissolved substances in seawater is 3.5%. How many grams of dissolved substances are in 200 grams of saltwater? A. 3.5 B. 7.0 C. 57 D. 200
85 Quick CheckWhich shows the correct order of Earth’s three major oceans from largest to smallest?Pacific, Atlantic. IndianAtlantic, Pacific, IndianIndian, Atlantic, PacificAtlantic, Indian, Pacific
86 Quick CheckWhich continents border the Atlantic Ocean? A. North America, Asia, Australia B. Asia, Australia, Africa C. North America, South America, Europe, Africa D. South America, Europe, Asia, Africa
87 Quick Check Salinity is the average amount of ________ Dissolved in water.sugaroxygencarbon dioxidesalt
88 Quick CheckWhat is the salinity of saltwater? As you descend deeper into the ocean temperature _____________ and pressure __________. The two sources of oxygen in ocean water are __________ and __________.
89 EQ: What are some features of the ocean floor? Exploring the OceanEQ: What are some features of the ocean floor?
90 Exploring the OceanWhat factors make ocean floor research difficult ? (2)What is SONAR? (5)What are some features of the ocean floor ? (7)
91 What factors make ocean floor research difficult? Scientists had to develop new technology to study the deep ocean floor because of three factors:cold temperatureincreased pressuredarknessAs you descend deeper into the ocean, these (3) factors increase
92 SONAROceanographers have mapped the ocean floors by using special equipment.SONAR stands for sound navigation and ranging. It is a system that uses sound waves to calculate the distance to an object.Oceanographers study the oceans by:-sonar -satelliteEcho sounding, (pings), measure the time it takes a pulse of sound to go from the ship to the ocean floor and echo back to the ship.The speed of sound in sea water averages about 1520 m per second.
93 What are some of the features of the ocean floor? The seven features of the ocean floor are:Continental shelf: a gentle sloping, shallow area of the ocean floor that extends outward from the edge of the continent.Continental slope: marks the true edge of a continent, a steady slope where rock that makes up the continent stops and the rock that makes up the ocean floor begin.Seamounts: mountains completely under water; extinct volcanoes
94 What are some of the features of the ocean floor? Abyssal plain: smooth, flat region of the ocean floorMid-ocean ridge: a continuous range of mountains that wind around Earth’s ocean floor.Volcanic Island: very tall mountains created by the cooling and hardening of erupting volcanoes on the ocean floor.Deep-sea Trench: canyons on the ocean floor that are the deepest spots on Earth.Guyot: a flat-top seamount flattened by the action of waves
96 Answers to Exploring the Ocean Darkness, cold, and extreme pressureSound navigation and ranging, is a system that uses sound waves to calculate the distance to an objectMid-ocean ridge – a continuous range of mountains that winds around EarthTrench – a steep sided canyon in the deep ocean floorContinental slope – an incline at the edge of a continental shelfAbyssal plain – the smooth, nearly flat region of the ocean floorSeamount – a mountain that is completely under waterContinental shelf – a gently sloping, shallow area of the ocean floor that extends outward from the edge of a continentVolcanic island – the peak of a volcano that beaks the ocean surface
97 Quick CheckA smooth, nearly flat region of the ocean floor is call a(n) A. trench. B. mid-ocean ridge. C. abyssal plain. D. sea mount.
98 Quick CheckWhich ocean floor feature makes up the deepest parts of the ocean? A. abyssal plain B. mid-ocean ridge. C. deep-sea trench. D. sea mount
99 Quick CheckWhat three (3) factors make ocean floor research difficult?_____________
100 Quick CheckWhat are some features of the ocean floor?__________
101 Lesson 12 Waves, Currents, and Tides EQ: What causes the ocean to move?
102 WavesA wave is a disturbance that transfers energy through matter or space.Wind transfers energy into the sea causing waves to occur.Undersea earthquakes and landslides can also put energy into the water to produce ocean waves.
103 WavesThe size of a wave depends on the amount of energy that is transferred to the water.The amount of energy transferred depends on three things:Wind speedLength of time it blowsDistance over which it blowsAs each of these factors increase, so does the size of the wave.
104 Ocean Currents Winds are responsible for ocean currents. A surface current is an ocean current that moves along the top part of an ocean.Surface currents are moved by prevailing winds.Prevailing winds are winds that blow in regular directions almost all the time.
105 Ocean Currents Surface currents can be cold or warm. Those that flow from the poles toward the equator are cold.Those that flow from the equator towards the poles are warm.The Gulf Stream is a warm current that flows northward up the east coast of the United States toward Great Britain and western Europe.
106 TidesA tide is the rise and fall of the ocean’s surface caused mostly by the gravitational pull of the moon.At high tide, the ocean water has risen as high as it will go on a shore.At low tide, the ocean water has fallen as low as it can go on a shore.
107 TidesEarth’s rotation on its axis affects which tides will occur at a certain place on Earth.High tides occur about every 12 hrs.Low tides occur about every 12 hours.The time between low tide and high tide is about 6 hrs.
108 Quick CheckWhat causes tides but NOT waves and currents? A. winds and the moon’s gravity B. mostly the moon’s gravity C. mostly the sun’s gravity D. only winds
109 Quick CheckWhat is the main cause of the Gulf Stream? A. storms B. winds that blow now and then C. winds that blow in regular directions D. the moon’s gravity
110 Quick CheckIf the first high tide of the day occurs at 1:00 a.m., the next high tide will come closest to A. 7:00 a.m. B. 7:00 p.m. C. 1:00 a.m. the next day D. 1:00 p.m.
111 Quick CheckWhat is the cause waves and currents but NOT tides? A. wind B. the moon’s gravity C. the sun’s gravity D. Earth’s gravity
112 Quick Check What is the cause of most ocean waves? The climate The large ships in the oceanThe moonThe wind
113 Quick CheckA wave will increase in height when the distance over which the wind blows over the seaA. increases.B. decreases.C. stays the same.D is 0 kilometers.
114 Quick CheckThe wave will increase in height when the speed of the windA. remains unchanged for a long time.B. decreases.C. increases.D. changes direction.
115 Quick CheckWhich will produce the highest wave? A. wind speed of 10 km/h B. wind speed of 20 km/h C. wind speed of 30 km/h D. wind speed of 40 km/h
116 Quick CheckWhich unit of measurement would you use to express the area of the Atlantic Ocean? A. m B. km C. m² D. km²
118 Wave ActionHow does a wave form?How does wavelength and wave height change as a wave enters shallow water?What factors determine the size of a wave?
119 EQ:What Causes a Waves to Form? A wave is a disturbance that transfers energy through matter or space.Most waves form when winds blowing across the water’s surface transmit their energy to the water.Wind transfers energy into the sea causing waves to occur.Undersea earthquakes and landslides can also put energy into the water to produce ocean waves.
121 Describing Waves Crest – highest part of a wave Trough – lowest part of a waveWavelength – horizontal distance between crests or troughsWave height – vertical distance from the crest to the troughFrequency – number of waves that pass a point in a certain amount of time
123 How does the water move in a wave? Like the bottle in the picture, water remains in the same place as wave travel through it.
124 Size of a WaveThe size of a wave depends on the amount of energy that is transferred to the water.The amount of energy transferred depends on three things:Wind speedLength of time it blowsDistance over which it blowsAs each of these factors increase, so does the size of the wave.
125 How Waves Change Near Shore In deep waters, waves travel as long, low waves called swells.Near shore, the wave height increases and the wavelength decreases.When the wave reaches a certain height, the crest of the wave topples. The wave breaks onto the shore, forming surf.
127 How Waves Affect the Shore Longshore Drift – movement of sand along the beach at an angleRip Currents – a rush of water that flows rapidly back to sea through a narrow openingSandbar –as waves slow down, they deposit the sand they are carrying on the shallow, underwater slope in a long ridge
130 Reducing Beach Erosion Over time, erosion can wear away a beachThreatens homes, buildings, propertygroin – a wall of rocks or concrete to reduce erosion along a stretch of beachBuilding groins can increase the amount of erosion father down the beach
131 Answers to Wave Action Crest Wavelength Trough Wave height The waves height increases and its wavelength decreasesWhen the waves come into the shore at an angle, resulting in a movement of sand along the beachBuild a groin8. Wave – the movement of energy through water (b)9. Frequency – the number of waves that pass a point in a given amount of time (d)10. Longshore drift – the movement of sand down a beach (a)11. Sandbar – a long, low ridge of sand deposited offshore as waves go back out to sea (c)12. Rip current – a rush of water that flows out from the shore through a narrow opening (f)13. Groin – a wall of rocks or concrete built outward from a beach to prevent erosion (e)
132 Quick Check What is the cause of most ocean waves? The climate The large ships in the oceanThe moonThe wind
133 Quick CheckA wave will increase in height when the distance over which the wind blows over the seaA. increases.B. decreases.C. stays the same.D is 0 kilometers.
134 Quick CheckThe wave will increase in height when the speed of the wind A. remains unchanged for a long time. B. decreases. C. increases. D. changes direction.
135 Quick CheckWhich will produce the highest wave? A. wind speed of 10 km/h B. wind speed of 20 km/h C. wind speed of 30 km/h D. wind speed of 40 km/h
136 Quick CheckRolling waves with a large distance between crests have a longwave heightwavelengthfrequencytrough
137 Quick Check Groins are built to reduce the effect of tsunamis. longshore drift.rip currents.deep currents.
138 Quick Check Sand is gradually carried down the beach by groins sandbarscrestslongshore drift
139 EQ: What forces cause surface currents and deep currents? SectionCurrents and ClimateEQ: What forces cause surface currents and deep currents?
140 What Causes Surface Currents to Move? What force causes surface currents? How do surface currents affect climate on land? What force cause deep currents? What is El Niño?
141 What is the difference between a wave and a current? Studyjams Watch the Study Jams video!
142 Surface CurrentsSurface currents are driven mainly by winds and follow global wind patterns, moving in circular patterns in ocean basins.Surface currents affect water to a depth of several hundred meters.Coriolis effect- the effect of Earth’s rotation on the direction of winds and currents
144 Surface Currents Winds are responsible for ocean surface currents. A surface current is an ocean current that moves along the top part of an ocean.Surface currents are moved by prevailing winds.Prevailing winds are winds that blow in regular directions almost all the time.
147 How Surface Currents Affect Climate A surface current warms or cools the air above it, influencing the climate of the land near the coast.Currents are large streams of moving water that flow through the oceansCurrents affect climate by moving cold and warm water around the globe.Climate is the pattern of temperature and precipitation typical of an area over a long period of time.
150 Deep CurrentsDeep currents are caused by differences in density rather than surface winds.Cold waters at the bottom of the ocean creep slowly across the ocean floor.Deep currents move and mix water around the world.They move much slower than surface currents.
152 UpwellingUpwelling is the upward movement of cold water from the ocean depths.As wind blows away the warm surface water, cold water rises to replace it.Upwelling brings up tiny ocean organisms, minerals, and other nutrients from the deeper layers of the water.
154 El NiñoEl Niño- an abnormal climate event that occurs every 2 to 7 years in the Pacific Ocean.This causes a sheet of warm water to move eastward toward the South American coast.El Niño can last for one to two years before the usual winds and currents return.This damage in Southern California was the result of excessive rain caused by El Niño in 1997
155 Answers to Currents and Climate SurfaceWarm or coldDifferences in densityColdBy moving warm or cold water around the globe, warming or cooling the air above6. Upwelling increases the supply of nutrients by bringing up tiny ocean organisms, minerals and other materials from the deeper layers of the water7. CurrentsCoriolis effectClimate10. El Niño
156 Quick Check Currents are caused by gravitational pull of the moon. gravitational pull of the sun.Winds, the earth’s rotation, and differences in water density.the earth’s rotation.
157 Quick Check Winds and currents move in curved paths because of the Coriolis effect.longshore drift.wave height.tides.
158 Quick Check What is the MAIN cause of the Gulf Stream? A. storms B. winds that blow now and thenC. winds that blow in regular directionsD. the moon’s gravity
159 Tides EQ: What causes tides? SectionTidesEQ: What causes tides?
160 TidesWhat causes tides? How can tides be used to generate electricity? Describe the positions of the sun and the moon, in relation to Earth when spring tides occur.
161 What causes tides?Tides are caused by the interaction of Earth, the moon, and the sun.The moon pulls on the water on the side closest to it more strongly than it pulls on the center of the Earth.This pull creates a bulge of water, called a tidal bulge, on the side of Earth facing the moon.The water opposite the moon is pulled toward the moon less strongly than the water facing the moon.This water is “left behind,” forming a second bulge.
162 The Daily Tide CycleAs Earth turns completely around once each day, people on or near the shore observe the rise and fall of the tides as they reach the area of each tidal bulge.The high tides occur about 12 hrs. and 25 mins. Apart in each location.
163 Tides occur at different locations on Earth because the Earth rotates more quickly than the moon revolves around the Earth.
165 The Monthly Tide CycleChanges in the positions of Earth, the moon, and the sun affect the height of the tides during a month.Twice a month, at the new moon and the full moon, the sun and moon are in a straight line.Their combined gravitational pull produces the greatest range between high and low tide, called a spring tide.In between spring tides, at the first and third quarters of the month, the sun and moon pull at right angles to each other, producing a neap tide.A neap tide is a tide with the least difference between low and high tide.The movement of large amounts of water between high and low tide are a source of potential energy—energy that is stored and waiting to be used.
167 Answers to Tides A and D C or E Spring Lower Greater 7. Neap tide – tide with the least difference between high and low tide (c)8. High tide – tide in which water reaches its highest point on the beach each day (d)9. Spring tide – tide with the greatest difference between high and low tide (a)10. Low tide – tide in which water reaches its lowest point on the beach each day (b)
168 Quick Check What causes tides but NOT waves and currents? A. winds and the moon’s gravityB. mostly the moon’s gravityC. mostly the sun’s gravityD. only winds
169 Quick CheckAt the full moon, the combined gravitational pulls of the sun and the moon produce a A. surface current. B. neap tide. C. spring tide. D. rip current.
170 Quick CheckA tide which water reaches its lowest point on the beach each day is called A. neap tide. B. high tide. C. spring tide. D. low tide.
171 Quick CheckTide with the least difference between high and low tide is called A. neap tide. B. high tide. C. spring tide. D. low tide.
172 Quick CheckA tide in which water reaches its highest point on the beach each day is called a A. neap tide. B. high tide. C. spring tide. D. low tide.
173 Quick CheckIf the first high tide of the day occurs at 1:00 am, the next high tide will come closest toA. 7:00 amB. 1:00 am the next dayC. 7:00 pmD. 1:00 pm
174 Quick CheckTide with the greatest difference between high and low tide is called a A. neap tide. B. high tide. C. spring tide. D. low tide.
175 Quick CheckHigh tides occur A. once every two days. B. once a day. C. twice a day. D. four times a day.