Properties of Ocean Water

Today you are going to… complete the salinity lab. So you can… calculate salinity problems and understand the effect salinity has on density and organisms. You’ll know you’ve got it when…you can • Create 3 layers of water with different salinities • Answer the lab questions

Where did Earth come from?

Where did Earth come from? • Nebular theory

Where did Earth from? • Nebular theory

Where Earth’s water come from? • • • •

4.6 billion years ago, Earth’s surface formed. Comets had smashed into Earth, bringing water. Volcanoes vented gasses, including water vapor. At first, Earth was so hot that water just stayed in the atmosphere as clouds. • Eventually, hot rains fell, only to boil on Earth’s hot surface & rise back into the atmosphere. • It rained constantly for 20 million years, but gradually Earth’s surface cooled and oceans formed.

How much water is in the ocean? • About 1,300,000,000 km3 (340,000,000 mi3) of water in the oceans (an estimate by NOAA) – Some other estimates are a bit lower or higher – so much water that it is impossible to comprehend how much it is.

• 36,000,000,000,000,000,000 • That’s 36 quintillion gallons!

(3.6 x 1019 gal)

How much water is in the ocean? • If you poured all of the world's water on the United States, you'd create a lake 145 km (____ miles) deep. – In the thermosphere! – Above all clouds, birds, planes. – Above most shooting stars! – That’s only 9 miles below the Lowest satellite! Is about the distance from here to Breezewood!

• It would take 19 Shamwows to dry up the Global Ocean. • Shamwows are amazing.

• About 70 % of freshwater is locked in ice caps. • Less than 1 percent of the world's water is readily accessible, and not all of that water is clean.

Water Wars? • 6 countries (Brazil, Russia, Canada, Indonesia, China and Colombia) have 50 percent of the world's freshwater reserves • One-third of the world's population lives in "waterstressed" countries. – – – –

They use more water than they have, so they have to import it. consume 20 percent more water than their available supply. If they have 200 gallons, they’re consuming _______ gallons. Conflict could arise when one country uses up or pollutes a river that flows into another country.

How much water is consumed annually? • • • • •

About 5,000,000 billion liters according to the UN That’s 5,000,000,000,000,000,000 liters 5 quintillion liters About 1 quintillion gallons http://www.worldometers.info/water/

Properties of Ocean Water • Polarity – Surface tension, cohesion, & adhesion – Specific heat – climate control – Dissolves gasses & solids

• Temperature • Density

H2O (Water) is a Polar Molecule • • • •

The oxygen atom has a slight negative charge The hydrogen atoms have a slight positive charge The – O atoms & +H atoms attract, so they kind of “stick together” Called hydrogen bonding

H2O & Hydrogen bonding • Hydrogen bonding leads to: – Cohesion – water sticks together – Surface tension – tendency of surface of a liquid to resist an outside force • Water’s high surface tension bugs walk on water!

Kill Fruitflies!

1. Where did the oceans come from? 2. There are _____ gallons of water in the ocean. Humans consume _____ gallons of water each year. 3. If you poured all the worlds water on the USA, you’d create a lake _____ miles deep. 4. ______% of Earths water is fresh water, and _____% of the fresh water is frozen. Less than _____% of Earth’s water is available. 5. _____ of Earth’s population lives in water stressed countries, which means they have to _____ water because they don’t have enough. 6. What makes water molecules special? They’re _____! 7. Water molecules “stick together”, which is called c_____. 8. _____ is the tendency of surface of a liquid to resist an outside force. 9. Why can water bugs sit on water? (water has a high ___ ___)

Heat Capacity • Heat Capacity – measure of the heat required to raise temperature of 1 g of a substance 1oC • Water has an extraordinarily high heat capacity because of the hydrogen bonds – Some of the heat energy goes to weakening hydrogen bonds

• This means water’s temperature doesn’t change much when heat energy is added or removed.

Heat Capacity • Water heats up & cools off much slower than land (or anything else). • Important! Since 71% of Earth’s surface is water, Earth heats up & cools off slowly. (slower than land)  – Keeps Earth from getting really hot or cold.

Student Demo!!!!! Take a paperclip, cup, water bottle or beaker, & pipette Fill the water as high over the lip as you possibly can Add a paperclip

Solubility • Water is the universal solvent! It dissolves lots of stuff. Even gases!

Dissolved Gases • 3 most common are N2, O2, CO2 • Sources – Underwater volcanic eruptions – Gases released by marine organisms – Waves dissolve the gases in our atmosphere. – Stream/river water bring gasses into ocean

Dissolved Gases • Carbon dioxide is one of the most important gases that dissolve in the ocean.

Oceans & Global Warming (Climate Change) • https://www.youtube.com/watch?v=ztWHqUFJRTs

The Oceans as a Carbon Sink • Ocean holds 60x as much carbon as air – Called a “carbon sink” • Carbon sink - anything that absorbs more carbon than it releases • Carbon source - anything that releases more carbon than it absorbs

• Where does the carbon go? – Some CO2 stays as dissolved gas, but most reacts with the water to form carbonic acid or bicarbonates. This removes dissolved carbon dioxide from the water. – Plants & animals use carbonates in water to form shells. – Shells sink to the bottom when plants & animals die.

The Oceans as a Carbon Sink • The ocean absorbing CO2 is great, because CO2 is a greenhouse gas. • The less CO2 in our atmosphere, the less global warming.

Questions! 1. 2. 3. 4. 5. 6. 7.

What is heat capacity? Why is it good for Earth that water has a high heat capacity? What are the three most common gases in the ocean? What are 4 ways gasses get dissolved into the ocean? A carbon _____ releases more carbon than it absorbs. A carbon _____ absorbs more carbon than it releases. How does the ocean absorb carbon?

Temperature & GAS Solubility • Cold water dissolves gasses more readily – Cold water holds more gasses than warm water • If ocean temperature rises, it releases gases into atmosphere • If ocean temperature drops, it absorbs gases from the atmosphere

Oceans & Global Warming (Climate Change) • https://www.youtube.com/watch?v=ztWHqUFJRTs • More greenhouse gases in our atmosphere (CO2) are warming the atmosphere • The warmer atmosphere warms the oceans • The oceans hold less CO2 because warmer water holds less gasses – An opened bottle of pop goes flat _________at room temperature than in the cold fridge.

The Oceans as a Carbon Sink

Oceans & Global Warming • Changing wind patterns caused by global warming may also be making the ocean less of a carbon sink  • In the Southern Indian Ocean, climate change is leading to stronger winds, which mix waters, bringing CO2 up from the ocean depths to the surface. – This is the conclusion of researchers who have studied the latest field measurements.

• As a result, the Southern Ocean can no longer absorb as much atmospheric CO2 as before. • Its role as a 'carbon sink' has been weakened, and it may now be ten times less efficient than previously estimated. • The same trend can be observed at high latitudes in the North Atlantic.

Could the ocean ever flood the entire Earth? • If all the ice on Earth melted… • http://ngm.nationalgeographic.com/2013/09/risingseas/if-ice-melted-map

Questions! 1. Why is the ocean salty? (3 sources, what happens when salt water evaporates) 2. How many gallons of water are in the ocean? 3. How deep would the lake over the U.S. be? 4. How much of Earth’s water is fresh water? 5. How much of the fresh water is easily accessible? 6. Where is most of Earth’s fresh water? 7. What is a carbon sink? 8. How is Earth’s increasing temperature affecting the ocean’s effectiveness as a carbon sink?

Bell Work 4/10/14 – 5 min 1. The average salinity of the Great Salt Lake is 17.2%. How many lbs of salt would be in 20,000 lbs of Great Salt Lake water? 2. In 49 lbs of water there are 3.2 lbs of salt. What’s the salinity in % and ppt?

Today you are going to… take So you can… begin Calculate percent salinity and parts per thousand, and convert between the two • Identify the dissolved gases and solids found in ocean water and their sources • Explain how temperature affects the solubility of gases and solids in water

You’ll know you’ve got it when…you can • Define:

Dissolved Solids • Ocean water also has solids dissolved in it! • Water dissolves stuff really well because it’s _____!

The Composition of Seawater Ocean water contains over 70 elements! The most common salt in ocean water is sodium chloride (NaCl), or common table salt…yum! Chloride is the most abundant ion in seawater.

Dissolved Solids • What solids are dissolved in ocean water? – Ocean water contains over 70 elements! – Cl, Na, Mg, S, Ca, K • (chlorine, sodium, magnesium, sulfur, calcium, potassium)

– most common salt is sodium chloride (NaCl), AKA halite, or table salt

• Trace elements – include gold, zinc, phosphorus

Cl, Na, Mg, S, Ca, K

Sources of Dissolved Solids • Most dissolved solids are salts • 4 main sources – chemical weathering of rock on land • Rivers dissolve salt from rocks. • Rivers - 400 billion kg (880 billion lbs) of solids per year (mostly salts)

– chemical reactions between sea water & new sea-floor – Hydrothermal vents – Volcanic eruptions

• Salt stays behind when water evaporates • Organisms take salt out of ocean water, therefore the salinity stays pretty constant

Salinity of Ocean Water • Salinity – measure of the amount of dissolved salts & other solids in given liquid • You could say it’s the “saltiness” of water. • The ocean has an average of 3.5% (35 ppt) salinity.

The ocean has an average of 3.5% salinity. • Percent or % means parts per hundred – 3.5 % means of 100 grams of ocean water, 3.5 grams are salt. (the other 96.5 grams are water)

• Ppt or %o means parts per thousand – 35 %o (35 ppt) means of 1000 grams of ocean water, 35 grams are salt. (the other 965 grams are water)

Variations in Salinity • Salinity varies from place to place because of several processes. – If you added fresh water to a cup of salt water, would the salinity increase or decrease? – If you removed some fresh water from a cup of salt water, leaving the salt behind, would the salinity increase or decrease?

Processes That Decrease Local Salinity • All involve adding fresh water to ocean! 1. Rivers entering ocean 2. Precipitation (rain, snow, sleet, hail) 3. Ice melting • Ice is fresh water…very little salt freezes in ice, even in the ocean!

Processes That Increase Salinity • Both involve removing fresh water from ocean 1. Evaporation (salt stays behind) 2. Ocean water freezing (salt stays behind)

Variations in Salinity (not in notes) • Salinity is lower in areas where: – rivers empty freshwater into the ocean. – It rains a lot. – temperatures are moderate.

Salinity is higher in areas where: -- it’s hot…ocean water evaporates, leaving salt behind, so the ocean water there has a higher salinity. -- it’s cold…ocean water freezes. The salt does not freeze with the ice, instead mixing into the rest of the ocean water, making it saltier.

Dissolved Solids *_____________ water can dissolve more solids than __________ water. It’s the opposite of gases.

The Saltiest Sea – The Dead Sea

The Saltiest Sea – The Dead Sea

• On boarder of Jordan and Israel

The Saltiest Sea – The Dead Sea • Lowest point below sea level – 1400 ft! • Average high 103oF (record 116.6oF) • Formed as Mediterranean Sea flooded during storms, water was trapped & evaporated – Eventually land between rose, so this doesn’t happen anymore. As a result, the Dead Sea is shrinking. – Dense sediments settled there, pushing salt up • Like a rock set on top a bucket of mud

• During Miocene Epoch, Straits of Gibraltar were closed off • Mediterranean sea was cut off & evaporated • Produced layer of halite & must have caused temps to rise to 120oF in neighboring landmasses

The Saltiest Sea – The Dead Sea

Dead Sea Video • https://www.youtube.com/watch?v=12HIErm CqQI • Because the water is very ___________________, it is very ____________________, making it easier for people to ________________.

Calculating Salinity • Percent: There are 83 grams of salt in a 500 gram sample of seawater. What is the percent salinity?

• PPT: There are 80 grams of salt in a 500 gram sample of seawater. What is the salinity in parts per thousand?

Calculating Amount of Salt in Water • A sample of seawater has a salinity of 12%. How many pounds of salt would be in 4 pounds of this water?

Bell Work 1. W5SAYWoS 2. Where would you like to sit?

Schedule

Thursday Review S.G. Notes on Ocean Temperature Layers Grades & Study Guide Friday Why is ocean blue? Lab Due! Pressure! Monday Why is ocean blue? Pressure! Density Tuesday Review for test Wednesday Test Thursday 24.2 Ocean Life Reading Guide

Temperature of Ocean Water • Varies depending on depth & location • 3 layers based on temperature – Mixed Layer – Thermocline – Deep

1. Mixed Layer (Surface water) – Sunlight affects temp – Surface currents also affect temp • Like rivers flowing on surface of ocean!

1. Mixed Layer (Surface water) • • • • •

Top 100 – 300 meters Warmed by sun Well mixed by currents & wind Temperature decreases slightly Temperature decreases as latitude increases • Tropical waters, temperatures of 30oC (86oF) common

• Ocean water freezes at - 1.9oC (28.6oF) • Pack ice – floating layer of ice up to 5 m (16 ft) thick – Insulates water below, keeping ocean warm – Prevents evaporation (a cooling process) • Sling psychrometer

– If ice didn’t float, the ocean would mostly freeze solid! – Coffee mug!

Pack Ice

Thermocline • Water temperature drops with increased depth • Forms because less dense warm water doesn’t mix easily with the denser cold water – Pour colored warm water

Deep Water • Water is about 2oC (36oF) • Generally colder water is denser and contains more dissolved gases

Density of Ocean Water • Density – how compact something is, mass/volume – Paper more & less dense – Container more & less dense

Density of Ocean Water • 2 things affect density of ocean water 1. Temperature – colder is denser (draw pic of molecules, ball, water 2. Salinity – saltier is denser (pic of salt dissolved in water on next page)

• Temperature affects density more than salinity does • The densest ocean water is found in _______________ regions because it’s coldest AND it gets saltier as water _________________, leaving salt behind

Density of Water • Most things are more dense in solid form than liquid form, but water is different because it is polar. • Ice is less dense than water!!!!! – Colored Ice Cube Demo

• The density of fresh water at 4oC is 1.0 g/cm3, while the density of ice at 0oC is only 0.92 g/cm3.

Pressure! • 1 gallon of water = 8 lbs

Pressure! • Pressure at sea level 14.5 psi (weight of air) • 33 feet of water = 14.5 psi • In deepest ocean, the pressure is equivalent to the weight of an elephant balanced on a postage stamp, or the equivalent of one person trying to support 50 jumbo jets! • Many animals that live in the sea have no trouble at all with high pressure. Whales, for instance, can withstand dramatic pressure changes because their bodies are more flexible. Their ribs are bound by loose, bendable cartilage, which allows the rib cage to collapse at pressures that

Pressure! • • • •

Freedive https://www.youtube.com/watch?v=YtryV9qItsg Record scuba dive is a little over 1000 feet. Can descend quickly, but must come back up slowly due to effect of pressure on blood

Pressure! • Many animals that live in the sea have no trouble at all with high pressure. Whales, for instance, can withstand dramatic pressure changes because their bodies are more flexible. Their ribs are bound by loose, bendable cartilage, which allows the rib cage to collapse at pressures that would easily snap our bones. • A whale's lungs can also collapse safely under pressure, which keeps them from rupturing. This allows sperm whales to hunt for giant squid at depths of 7,000 feet or more.

Bell Work 11/11/13 – 4 min Get study guide out so I can check it 1. Why does the ocean form layers based on temperature? 2. Which is the warmest layer? 3. Which is the thickest layer? 4. In which layer does temperature change the most? 5. W5SAYWoS

Bell Work 4/14/14 – 4 min 1. A “swamp cooler” is an inexpensive and effective method of cooling houses in dry areas. A fan is blown over wet straw. Why does this cool the house? 2. How does pack ice insulate ocean water? 3. W5SAYWoS

Why is the ocean blue?

Why is the ocean blue? • Because the sky is blue? • NOOOOOO!!!!!!!!!! THAT IS WRONG!!!!!!!!!!!!!!!! DON’T YOU SAY THAT. DON’T YOU EVER SAY THAT!

Spectrum of Light Rabbits mate in very unusual expensive gardens

White light is the blend of all colors. Pass around prism!

Why are different objects different colors? • White light is the blend of all colors. • The sun emits all wavelengths. – Really, our sun is pretty much white.

• If an object looks white, it absorbs very little visible light, reflecting almost all of it. • If an object looks red, it absorbs all light except red, which it reflects. • If an object looks green, it absorbs all light except green, which it _________________.

Why are different objects different colors? • If an object looks blue, it ______________________________ • A glass of pure water appears clear because it absorbs very little light. – Most light passes right through, but it does absorb some light. – Water absorbs red, orange and yellow (long wavelength light) more strongly than blue (short wavelength light). – When white light from the sun enters the ocean, it is mostly the blue that gets returned. – If you look through 5 meters (_____ft) of water, it starts to look blue. – The deeper the water is, the more light absorbed, and darker blue it looks. – Eventually it looks black, as all light is absorbed. (not surface of water)

Why is snow blue?

Why are Glaciers blue?

Why is the ocean blue? The apparent color of water is affected by 4 things. 1. Depth of water 2. Color of bottom of lake/ocean 3. Light reflecting off surface of water

Why is the water bluer in that circle?

But ocean water isn’t always blue! • Phytoplankton (tiny floating ocean plants) can make the water look green

• Currents cause upwelling • Greens & blues are different critters • Browns are sediments • More info at: –

http://science.nasa.gov/earth-science/oceanography/livingocean/ocean-color/

Red Tide

Why is this lake a different color blue?

Water in northern part of Great Salt Lake Pink Lemonade Colored due to bacteria!

3. Color of ocean floor can also affect color.

4. Light Reflecting From Sky (You realize it’s the sky & not the water though.)

Light Reflecting from sky

Why is Ocean Color Important? • Can indicate health of ocean • Phytoplankton – microscopic plants in ocean – Absorb red & blue light, reflect green light – Presence of phytoplankton can be studied by studying color of ocean water – Phytoplankton = healthy ocean

• The colour in most of the world’s oceans varies with the concentration of chlorophyll and other plant pigments contained in the phytoplankton, the greater the concentration of plant pigments, the greener the water. As an orbiting sensor can view every square kilometre of cloud-free ocean every 48 hours, satellite-acquired ocean colour data are valuable for determining the abundance of ocean life and to assess the ocean’s role in climate change.

Bell Work 4/15/14 1. Why is a large amount of water blue, but a glass of water is clear? 2. List 3 other things that can affect the color of water.

• Why is water blue? (Or whatever color…) – Water absorbs little light. Water in a glass appears clear because such a small amount of water absorbs very little light. – Water absorbs more red light than blue, leaving blue behind. – Water color is also affected by: • Things suspended or dissolved in water • The color of the bottom of the ocean/lake • The reflection of the sky