The OceansThe Oceans

A Presentation on Atmosphere-Ocean Interaction

National Weather Service

Shreveport, LA

Presented by:

Why study major bodies of water?Why study major bodies of water?

• Water covers nearly ¾ of the earth’s surface

• More than 50% of the world’s population lives within an hour of the coast

• Plays a role in both climate and day-to-day weather

• FOOD!– Cost of your food could depend on it

The “Basics”The “Basics”

There are FOUR oceans• ATLANTICATLANTIC

• PACIFICPACIFIC

• INDIANINDIAN

• SOUTHERNSOUTHERN

Around the World in 4 Slides…Around the World in 4 Slides…

Begins at 60°SBegins at 60°S

Mediterranean SeaMediterranean Sea

Arctic SeaArctic Sea

Gulf of MexicoGulf of Mexico

Caribbean SeaCaribbean Sea

Around the World in 4 Slides…Around the World in 4 Slides…

Begins at 60°SBegins at 60°S

Gulf of AlaskaGulf of Alaska

Bering SeaBering Sea

Sea of JapanSea of Japan

Around the World in 4 Slides…Around the World in 4 Slides…

Begins at 60° SBegins at 60° S

Red SeaRed Sea

Persian GulfPersian Gulf

Arabian SeaArabian Sea

Around the World in 4 Slides…Around the World in 4 Slides…

Begins at 60° SBegins at 60° S““Defined” in 2000Defined” in 2000

Ocean or Sea, What’s the Big Deal?Ocean or Sea, What’s the Big Deal?

SEASSEAS• Delineated by land massesDelineated by land masses

– Doesn’t matter if they’re largely enclosedDoesn’t matter if they’re largely enclosed

• Also “communicate” with the oceanAlso “communicate” with the ocean

Strait of GibralterStrait of GibralterBlack Sea

Mediterranean Sea

AfricaAfrica

Europe

Gulf of MexicoGulf of Mexico

United States

MexicoMexico

Bragging Rights…Bragging Rights…

Which ocean is the biggest?

OCEANOCEAN SURFACE AREA [kmSURFACE AREA [km22]] OF ALL OF ALL OCEANS…OCEANS…

Atlantic 90,818,000 27.1%

Indian 68,556,000 20.4%

Pacific 155,557,000 46.4%

Southern 20,327,000 6.1%

Bragging Rights…Bragging Rights…

Which ocean has the most coastline?

OCEANOCEAN COASTLINE LENGTH [km]COASTLINE LENGTH [km]

Atlantic 111,866

Indian 66,526

Pacific 135,663

Southern 17,968

Water is Water…or is it?!Water is Water…or is it?!

FRESHWATERFRESHWATER• Rivers• Streams• Lakes

SALTWATERSALTWATER• Oceans• Gulfs• Seas

Water is Water…or is it?!Water is Water…or is it?!

QUESTION:QUESTION:Is saltwater the same everywhere?Is saltwater the same everywhere?

ANSWER:ANSWER:Nope.Nope.

In general, the Atlantic Ocean is the In general, the Atlantic Ocean is the “saltiest.”“saltiest.”

Please Pass the Salt…Please Pass the Salt…

• “Run-of-the-mill” concentration?– 3.5 grams/liter

• Like weather, there are areas of – HIGH salinity– LOW salinity

So, where are these “highs” and So, where are these “highs” and “lows”?“lows”?

Please Pass the Salt…Please Pass the Salt…

HH

HH

HH

HH

HH

LL

LL

LL

Mmmmm…Salty!Mmmmm…Salty!

DEAD SEA FACTS:DEAD SEA FACTS:• Really a large lakeReally a large lake• Water gets in, but not Water gets in, but not

out!out!– Fed by River JordanFed by River Jordan– Evaporation only way Evaporation only way

outout

• Has nearly 10 times the Has nearly 10 times the salinity of the oceans!salinity of the oceans!– Leads to increased Leads to increased

densitydensityDead Sea was named

because it had no life!

So??So??

The increased The increased

density means density means

just about just about anythinganything

will float!will float!

We can see this through the use of eggs!We can see this through the use of eggs!

We’re Goin’ Down, Down, Down…We’re Goin’ Down, Down, Down…

Just like the atmosphere, the Just like the atmosphere, the ocean has layers!ocean has layers!

The Epipelagic ZoneThe Epipelagic Zone

• ““Sunlight Zone”Sunlight Zone”– Most solar heatingMost solar heating– Lots of temperature Lots of temperature

changechange

• Surface to 200mSurface to 200m

• Influenced by Influenced by windwind

Bridge Over Troubled Waters…Bridge Over Troubled Waters…

• A transition layerA transition layer• Temperature Temperature

decreases rapidlydecreases rapidly• Relevance to you?Relevance to you?

– Higher bass Higher bass concentrations concentrations (oxygen is just right)(oxygen is just right)

The Mesopelagic ZoneThe Mesopelagic Zone

• ““Twilight Zone”Twilight Zone”– Most temperature Most temperature

change near top of change near top of layerlayer

• Between 200 and Between 200 and 1000m1000m

• Animal Animal characteristics characteristics begin to changebegin to change

The Bathypelagic ZoneThe Bathypelagic Zone

• ““Midnight Zone”Midnight Zone”– No light No light at allat all– Only light comes Only light comes

from animalsfrom animals

• Very little Very little temperature temperature changechange

• Pressure reaches Pressure reaches over 5800 p.s.i.over 5800 p.s.i.

The Abyssopelagic ZoneThe Abyssopelagic Zone

• ““The Abyss”The Abyss”– Greek word Greek word

meaning “no meaning “no bottom”bottom”

• Between 4000 Between 4000 and 6000mand 6000m

• Water Water temperature near temperature near freezingfreezing

The Hadalpelagic ZoneThe Hadalpelagic Zone

• ““The Trenches”The Trenches”

• Anything below Anything below 6000m6000m

• Worth repeating:Worth repeating:– Deepest trench is Deepest trench is

the Mariana Trenchthe Mariana Trench– ““Weight”: >8 t.s.i.Weight”: >8 t.s.i.

• Life still exists Life still exists here!here!

That’s That’s TONSTONS per per square inch!square inch!

Our Mr. SunOur Mr. Sun

• ““Driving Force”Driving Force”

• Solar radiation Solar radiation affects the ocean affects the ocean differentlydifferently– More on this laterMore on this later

• Ultimate cause of Ultimate cause of windwind

Ocean Currents – Just the FactsOcean Currents – Just the Facts

• Two types:Two types:– Wind-driven CurrentsWind-driven Currents– Deep Water CurrentsDeep Water Currents

• 40% of the global heat transport40% of the global heat transport

• Move slower than surface windsMove slower than surface winds– Kilometers per day vs. kilometers per hourKilometers per day vs. kilometers per hour

• Long-term climate impactsLong-term climate impacts– Gulf Stream most important in our regionGulf Stream most important in our region

Ocean Currents -- DevelopmentOcean Currents -- Development

• Oceans near Oceans near equator “heat up” equator “heat up” more than the polesmore than the poles

• Sets up…Sets up…– Temperature Temperature

imbalanceimbalance– Semi-permanent Semi-permanent

pressure areaspressure areas– Constant push of Constant push of

wind on waterwind on water

Ocean Currents – The Big PictureOcean Currents – The Big Picture

The Gulf StreamThe Gulf Stream

Dust in the Wind – During the DayDust in the Wind – During the Day

• Beach heats faster Beach heats faster than oceanthan ocean

• Air rises onshoreAir rises onshore• Slightly cooler, Slightly cooler,

denser air moves denser air moves onshore to replace onshore to replace the “lost” airthe “lost” air

• Results:Results:– Onshore breezeOnshore breeze– Possible storm Possible storm

developmentdevelopment

Dust in the Wind – At NightDust in the Wind – At Night

• Beach cools faster Beach cools faster than oceanthan ocean

• Air rises offshoreAir rises offshore• Slightly cooler, Slightly cooler,

denser air moves denser air moves offshore to replace offshore to replace the “lost” airthe “lost” air

• Results:Results:– Offshore breezeOffshore breeze– Possible storm Possible storm

developmentdevelopment

Wave ActionWave Action

• Another byproduct of windAnother byproduct of wind• Size depends on Size depends on THREETHREE things: things:

– SpeedSpeed– DurationDuration– DistanceDistance

• Longer the wave, the faster it movesLonger the wave, the faster it moves• Here’s a Here’s a cool factcool fact::

– You can estimate the wind speed using You can estimate the wind speed using the size of wavesthe size of waves

Battle of the BulgeBattle of the Bulge

• Tides are another Tides are another type of wave actiontype of wave action

• Definition:Definition:– A change in the A change in the

ocean water level, ocean water level, which results from which results from the gravitational pull the gravitational pull of the moonof the moon

POP QUIZPOP QUIZ

Where are the largest ranges Where are the largest ranges from high to low tide in the from high to low tide in the world?world?

Battle of the BulgeBattle of the Bulge

• Why the moon?Why the moon?– Sun’s gravitational Sun’s gravitational

pull is greaterpull is greater– But the moon is But the moon is

closercloser

• Mariners have Mariners have known for a long known for a long time that tides were time that tides were related to the moonrelated to the moon

Battle of the BulgeBattle of the Bulge

• Famous dead Famous dead people who have people who have studied tidal motion:studied tidal motion:– GalileoGalileo– DescartesDescartes– NewtonNewton– LaplaceLaplace– Lord KelvinLord Kelvin– KeplerKepler

POP QUIZPOP QUIZ

Where are the largest ranges Where are the largest ranges from high to low tide in the from high to low tide in the world?world?

HINT: HINT: It’s in North AmericaIt’s in North America

Two tides? Four tides?Two tides? Four tides?

• Number of tides per day related to…Number of tides per day related to…– Shape of the coastlineShape of the coastline– Sea floor elevationSea floor elevation

• Some places have one high/low tide Some places have one high/low tide cyclecycle– Called a Called a diurnal tidediurnal tide– Examples:Examples:

• Lake Charles, LALake Charles, LA• Gulfport, MSGulfport, MS• Gulf Shores, ALGulf Shores, AL• Pensacola, FLPensacola, FL

Two tides? Four tides?Two tides? Four tides?

• Number of tides per day related to…Number of tides per day related to…– Shape of the coastlineShape of the coastline– Sea floor elevationSea floor elevation

• Other places have two high/low tide Other places have two high/low tide cyclescycles– Called a Called a semi-diurnal tidesemi-diurnal tide– Examples:Examples:

• Galveston, TXGalveston, TX• Apalachicola, FLApalachicola, FL

Largest Tidal Range in the WorldLargest Tidal Range in the World

Bay of Fundy!Bay of Fundy!

High TideHigh Tide Low TideLow Tide

Where is the Bay of Fundy?Where is the Bay of Fundy?

The Knights Who Say “Neap”The Knights Who Say “Neap”

• Occur when the pull Occur when the pull of the moon and of the moon and sun partially cancel sun partially cancel each othereach other

• RESULT:RESULT:– Very little change Very little change

between high and between high and low tideslow tides

Springing Onward…Springing Onward…

• Occurs when the Occurs when the pull of the sun and pull of the sun and moon act togethermoon act together

• RESULT:RESULT:– Greater than normal Greater than normal

tidal range tidal range experiencedexperienced

About the Cost of Your Food…About the Cost of Your Food…

• Normally…Normally…– Warm waters over Warm waters over

Central PacificCentral Pacific– Cooler waters off Cooler waters off

Peruvian coastPeruvian coast

• Colder, nutrient-rich Colder, nutrient-rich waters pulled up waters pulled up from western coast from western coast of South Americaof South America

About the Cost of Your Food…About the Cost of Your Food…

• El Nino:El Nino:– Equatorial Equatorial

Countercurrent Countercurrent strengthensstrengthens

– Nutrient-rich water Nutrient-rich water supply lessenssupply lessens

• RESULT:RESULT:– Waters warm off Waters warm off

Peruvian CoastPeruvian Coast

About the Cost of Your Food…About the Cost of Your Food…

• La Nina:La Nina:– Weaker Equatorial Weaker Equatorial

CountercurrentCountercurrent– Nutrient-rich water Nutrient-rich water

supply increasessupply increases

• RESULT:RESULT:– Warm waters “pile Warm waters “pile

up” in the western up” in the western PacificPacific

What Does This Mean Weatherwise?What Does This Mean Weatherwise?

For El Nino Events – For El Nino Events –

What Does This Mean Weatherwise?What Does This Mean Weatherwise?

For La Nina Events – For La Nina Events –

So???So???

• A lot of fishing takes place off the coast A lot of fishing takes place off the coast of Peruof Peru

• Anchovy fish thrive in the nutrient-rich Anchovy fish thrive in the nutrient-rich waters of this areawaters of this area

• Anchovies are caught and used to Anchovies are caught and used to make chicken feedmake chicken feed

So???So???

• During big El Nino events:During big El Nino events:– Waters are not full as nutrientsWaters are not full as nutrients– Not as many anchoviesNot as many anchovies– Cost of chicken feed increasesCost of chicken feed increases– Therefore, the cost of chicken increasesTherefore, the cost of chicken increases

Thank You!!!Thank You!!!

Douglas ButtsDouglas ButtsSenior ForecasterSenior ForecasterWFO ShreveportWFO Shreveport

5655 Hollywood Ave.5655 Hollywood Ave.

Shreveport, LA 71109Shreveport, LA 71109

318.631.3669318.631.3669

CREDITS:CREDITS:

Texas A&M University Oceanography DepartmentTexas A&M University Oceanography Department

www-ocean.tamu.eduwww-ocean.tamu.edu

NWS Southern Region Jetstream ProgramNWS Southern Region Jetstream Program

www.srh.noaa.gov/srh/jetstreamwww.srh.noaa.gov/srh/jetstream

CREDITS:CREDITS:Texas A&M University Oceanography DepartmentTexas A&M University Oceanography Department

www-ocean.tamu.eduwww-ocean.tamu.edu

NWS Southern Region Jetstream ProgramNWS Southern Region Jetstream Program

www.srh.noaa.gov/srh/jetstreamwww.srh.noaa.gov/srh/jetstream