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ESC1000 • Earth Science • Summer 2016

Oceans and Coastlines

(Chapter 13)

The Atmosphere

(Chapter 14)

Weather Systems

(Chapter 15)

Chlorophyll and

net primary productivity

NASA animationshttp://earthobservatory.nasa.gov/GlobalMaps/view.php?d1=

MY1DMM_CHLORA&d2=MOD17A2_M_PSN

In-Class Activity: Observe the animation.

1. What do you see?

2. Why do you think this is important to oceanography?

Part of In-Class Activity #5: Today throughout lecture, I will ask you to

write down your observations about short animations and videos.

Look for the purple-highlighted sections in the slides.

Please submit your work before you leave (or before my office hours

end at 4 pm).

These animations, videos, and figures represent the major points

related to the ocean, atmosphere, and weather.

Take one breath. Then take a second breath.

Thank phytoplankton for your second breath.

Half of the world’s oxygen comes from the microscopic plant-like organisms

(phytoplankton) in the ocean. The other half comes from land (trees, other plants).

What are unique features of some bodies of water in

Florida?

- Kissimmee River, Lake Okeechobee, the Everglades

Which areas of Florida are prone to flooding, and why?

What are the major types of groundwater systems and

aquifers here? Which factors influence them?

How have the Everglades changed over time?

What is unique about this ecosystem?

Why are there so many invasive species in South Florida?

Unit 3 of ESC1000 (also known as the next two weeks)Learning Goals: Florida Ecosystems

5In boldface: These are the questions that you should focus on studying.

• Meandered 103 miles between

Lake Kissimmee and Lake

Okeechobee

• 1-3 mile wile floodplain, which

would hold excess water after

heavy rains

• Floodplain supported birds,

largemouth bass, eagles, alligators,

amphibians, and other wildlife

http://www.ces.fau.edu/riverwoods/kissimmee.php

Kissimmee River Changes

• Meandered 103 miles between

Lake Kissimmee and Lake

Okeechobee

• 1-3 mile wile floodplain, which

would hold excess water after

heavy rains

• Floodplain supported birds,

largemouth bass, eagles, alligators,

amphibians, and other wildlife

• 1947: extensive flooding due to hurricanes; flooding went into nearby cities

• People wanted flood control: 1948: Congress authorized the US Army

Corps of Engineers to start the Central and South Florida Project

• 1960-1971: Kissimmee River was transformed into one 56-mile-long canal

(300 feet wide, 30 feet deep): the C-38 canal

• Six water-control structures to manage flooding

• 90% decrease in birds overall; 70% decrease in bald eagles

• Largemouth bass replaced by fish that could tolerate lower oxygen levels

http://www.ces.fau.edu/riverwoods/kissimmee.php

Kissimmee River Changes

• C-38 canal gets backfilled

• Goal: restore flow and function to the river and reverse the stagnant, low-

oxygen conditions that drastically decreased the life in the river

• Measuring 25 criteria: water quality, vegetation, animals

• Return of wildlife that disappeared after the river was channelized

• 1992: Kissimmee River

Restoration Water

Resources Development Act

• Restore the middle third of

the channelized Kissimmee

• Project of the US Army

Corps of Engineers, plus the

South Florida Water

Management District

Kissimmee River Restoration:Largest river restoration project in the world

http://www.ces.fau.edu/riverwoods/kissimmee.php8

Exam 3 Bonus Opportunity

Rivers and wetlands:

What are the connections

among the Kissimmee River,

Lake Okeechobee, and the

Everglades?

Exam 3 Bonus Opportunity• Over the same time frame (1960-present), how have Lake

Okeechobee and/or the Everglades changed?

• How do you think that the Kissimmee River channelization

and restoration has played a role in these changes?

• What other factors may have influenced changes in these

water bodies?

(1) Lake Okeechobee – up to 3 points added

(2) The Everglades – up to 3 points added

You can do both of these, for up to 6 points added to Exam 3.

Exam 3 Bonus & Study Guide(1) Lake Okeechobee – up to 3 points added

(2) The Everglades – up to 3 points added

• Deadline: Monday, July 25 at 10 am, by email

• I will add highlights of your work to the exam reference

sheet, and most of the river/wetlands exam questions

will be based on what you find.

• I will post the study guide tomorrow and it will cover:

– Chapter 13 (Oceans and Coastlines)

– Chapter 14 (The Atmosphere – basics only!)

– Chapter 15 (Weather – hurricanes only)

– Climate Change and Sea Level Rise (use Chapters 16 and 17 as

reference: I will mostly present material related to South Florida)

Chapter 13: Oceans and Coastlines

1. Our Changing Oceans

2. Ocean Floor

3. Ocean Waters

4. Oceanic Circulation

5. Tides

6. Wave Action and Coastal

Processes

7. Shoreline Features

8. Shoreline Protection

The Good Earth/Chapter 13: Oceans and Coastlines

About 71% of Earth is covered with seawater.

The Oceans were mostly in place by ~4 billion years ago.

They are the final frontier for research on Earth.

Our Changing Oceans

• Oceans are

dynamic! Water is

continually in

motion. Oceanic

and atmospheric

circulation patterns

move heat around

and strongly

influence climate.

• Coastlines are also

dynamic, advancing

and retreating

depending on the

balance of erosion

and deposition. The Good Earth/Chapter 13: Oceans and Coastlines

The rugged coastline near Malibu, CA

Our Changing Oceans

• How do oceans/coastlines change?

− Coastlines can advance or retreat

− Short term, the position of the coastline can change depending

on daily tides and seasonal variations in stream flow

− Climate cycles measured over decades, centuries, or millennia

can show rises and falls in sea level

− Tectonic cycles occurring over thousands to millions of years

can revitalize coastlines through uplift

− Humans can influence oceans and coastlines as well, and be

strongly affected by oceans and their weather (e.g. hurricanes)

− More than ¼ of the U.S. population lives along the Atlantic and

Gulf coasts

Our Changing Oceans Self Reflection Survey

Answer the following questions as a means of uncovering what

you already know about oceans and coastlines:

How have you interacted with the world’s ocean,

either directly or indirectly?

Bathymetry (depth) of the Ocean Floor

− From what you learned about plate tectonics would you expect

the depths to be the same throughout the world’s oceans?

• The depth of the ocean (surface to floor) varies from zero meters (along

the coast) to a maximum of nearly 11 km (7 miles) along the Mariana

trench.

• Mt. Everest would sit in the trench with over 2,000 meters to spare!

(More than 1500 people have stood atop Everest – only 3 have visited

the deepest region of the ocean floor).

• Average land elevation is less than 1 km, but average ocean depth

is about 3.6 km (about 2 miles). Note: you may see different

numbers for the average ocean depth. The main point is that the

ocean is much deeper than the land is high.

• Volume of water in the oceans is nearly 10 times the volume of dry land

that lies above sea level.

• If erosion leveled the continents, all the eroded material would fit in the

ocean basins with room to spare! 17

Depth of the Ocean Floor

Sea Level is assumed to be zero meters

Sea level changes are due to changes in the shape of the ocean basins, or

long-term climate changes that trap water in ice caps or cause ice caps to melt.

The sea surface has bumps and low points – a satellite measures the

difference in height between the “bump” over a volcano and the

surrounding ocean. Radars on satellites are used to measure

variations in gravity, revealing ocean floor topography. 18

The Four Major Depth Zones = Continental shelf, Abyssal

plain, Oceanic ridge, Oceanic trenches

Passive margin zones: Continental shelf,

Continental slope, Continental rise, Abyssal

Active margin zones: Continental

shelf, Continental slope, Trench,

Abyssal Plain 19

Zone 3 - The Oceanic Ridge

• The oceanic ridge system is a submarine mountain chain that can be traced

around the world

• Ocean floor rises from the abyssal plain to the ridge

• 90% of Earth’s volcanic activity happens at ocean ridges

• Doesn’t heat the water much (rapidly dissipates)

• Depth is ~3 km above ridge crest

• Central valley beyond ridge crest – region of submarine hot springs (hot

smokers). They are home to some strange life!

A white crab and

tubeworm colony

found near a

hydrothermal vent.

The Origin of the Ocean(recall overview of Geologic Time)

− Early Earth was a hot mass of nearly molten rock

− Violent volcanic eruptions put gases, including water vapor, into

the air

− As Earth cooled this water vapor condensed into liquid water

− The more the planet cooled, the more water could collect in

hollows (“baby” oceans that grew into our present oceans)

− Although the water in the oceans has been around for ~4 billion

years, the present ocean basin configuration is the result of plate

tectonics, and no ocean basin is older than about 200 million

years old

− Even now, oceans and seas continue to grow or shrink as plates

diverge or converge

Ocean Waters: Water Chemistry

The oceans are “salty” because seawater contains dissolved salts and

minerals

Most of the dissolved solids in seawater is common salt (NaCl)

Salinity = the measure of the concentration of salt in seawater

More salt = higher density

Q: What variables

might influence

what parts of the

ocean (locations

around the globe)

are saltier than

others?

Ocean Waters: Salinity

Salinity is influenced

-Temperature

-Mixing caused by

currents

-Freshwater input

from rain, streams,

and melting ice

Salinity is highest

where temp is high

and precipitation is

(evaporation leaves

behind salts)

Properties of Water

In-Class Activity:

Why is water important?

Make a list of at least four important

properties of water,

during class today.

We’ll also review water properties during the

Atmosphere/Weather portion of class

(to be continued on Monday, 7/25).

Ocean Waters: Temperatures

Temperature of the oceans also varies with depth

decrease

in temps

with depth

in upper

meters

Rapid change in temperature with depth = thermocline

N-S profile

through Pacific

Ocean (150°W)

Factors influencing Density

Temperature and salinity are the most important factors

influencing density; also a uniform increase in pressure with

depth slightly increases density of the underlying water.

Temperature, Salinity, Pressure

Salinity, temperature,

and pressure combine

to create density profile.

Pycnocline = rapid

increase in density from

200 – 1,000 meters

depth.

“Cline” means a rapid

change in a certain

property.26

Gyres – surface currents

circulating around ocean basins

Three major causes

of gyres:

1.Surface winds

2.Sun’s heat

3.Coriolis effect

Oceanic Circulation

Ocean water is in constant motion!

Circular patterns (gyres) of ocean currents.28

Earth has 2 northern gyres, 4 southern.

North Pacific Gyre

Atlantic Gyre

South Pacific GyreSouth

Atlantic Gyre

Indian

Ocean Gyre

Circum - Antarctic Gyre

Surface currents can be illustrated by

sea surface temperature.

Red: 25°–28°Celsius (77°–82°F).

Yellow: 20°–25°C (68°–77°F);

Green: 15°–20°C (59°–68°F);

Blue: 0°–15°C (32°–59°F).

Purple: below the freezing point of fresh water.

Note the distortion of the temperature patterns we might expect

from the effects of solar heating alone—the patterns twist

clockwise in the Northern Hemisphere, counterclockwise in the

Southern.

Oceanic Circulation

• Coriolis Effect: Atmospheric

and oceanic circulation

patterns deflected to right in N

Hemisphere and to left in S

Hemisphere

• Earth rotates from west to east

• Objects near equator are

moving faster than those near

the poles (more distance to

cover in a day’s rotation)

• The planet beneath the

circulating wind/water moves

its position, leading to the

deflection

Imagine you are in Panama City, FL.

At noon you fire a rocket directly

north towards Columbus, OH. The

rocket has a northward velocity, but

also has a faster easterly velocity

due to Earth rotating east. The

rocket will land east of the city of

Columbus – the apparent deflection. 30https://www.youtube.com/watch?v=_36MiCUS1ro

Watch video for a simulation of the

Coriolis Effect:

The Coriolis Effect causes upwelling.

Upwelling: deep, cold, nutrient-rich waters move to the surface waters.

Upwelling stimulates growth of phytoplankton.

Upwelling:

cold water brings nutrients to the surface.

There are four major upwelling zones, and they are eastern boundary currents:

Where are they? 32

Upwelling:

cold water brings nutrients to the surface.

Canary Current

There are four major upwelling zones, and they are eastern boundary currents:

Where are they?

Benguela

Current

California Current

Humboldt Current

Oceanic Circulation: Thermohaline Circulation

Gulf Stream

• Carries high-salinity, warm waters from central Atlantic to higher

latitudes

• Water slowly cools as it travels north

• Cold, salty water sinks to the bottom of N Atlantic near Greenland and

Iceland

• Sinking water is then carried southward along bottom of the Atlantic

(North Atlantic Deep Water, NADW)

• Reaches Antarctica and is diverted eastward to the Indian and Pacific

• Deep current eventually comes up in N Indian and Pacific Oceans

(upwelling) – brings nutrients to surface waters

The pattern of deep currents is termed thermohaline circulation

(driven by both temperature and salinity)

Oceanic Circulation: Thermohaline Circulation

In-Class Activity, continued:

Watch this short video (link below) and describe what is happening.

How does density influence the water movement?

https://www.youtube.com/watch?v=EafneRiy1ls

Global Thermohaline Circulation

Oceanic Circulation: El Niño

El Niño and La Niña: The Earth system in action

Normal Year

Pacific ocean waters heated

Trade winds blow warm

water west

Cold upwelling occurs off

coast of SA

El Niño Year

Western trade winds diminish

Warm water remains in Pacific

Heavy rains occur in SA

Surface salinity decreases, reducing

upwelling

Droughts in western Pacific

La Niña Year

Cold conditions dominate

Droughts in SA, western US

Severe weather in western Pacific

Oceanic Circulation: El Niño

El Niño and La Niña: The Earth system in action

Normal Year

Pacific ocean waters heated

Trade winds blow warm

water west

Cold upwelling occurs off

coast of SA

El Niño Year

Western trade winds diminish

Warm water remains in Pacific

Heavy rains occur in SA

Surface salinity decreases, reducing

upwelling

Droughts in western Pacific 38

2015-2016 was an El Niño Year.

For South Florida, that usually means:

• Cooler temperatures

• More precipitation

• Lower likelihood of hurricanes (if it’s

colder)

There was more rain than normal, but

temperatures were not cooler. This is

because there are other things

happening with climate and

temperature: climate change and

increased atmospheric temperatures.

We are now starting La Niña, which

means that even higher temperatures

are expected. Therefore, hurricanes

are more likely this season.

Tides = changes in the sea surface height caused by the

gravitational attraction of the moon (and a bit by the sun)

• a) Spring tides – largest tidal bulges, highest tides

• b) Neap tides – smallest tidal bulges, lowest tides

Spring tide: Sun and moon exerting pull on

the Earth in same direction. Occur during

New Moon.

Neap tide: Sun and moon exerting pull on

the Earth in different directions. 39

Diurnal tides –

1 high tide in 24 hrs.

Semidiurnal tides –

2 high tides in 24 hrs.

Mixed tides –

High tides (and low tides)

vary in height

Diurnal tides –

1 high tide in 24 hrs.

Semidiurnal tides –

2 high tides in 24 hrs.

Mixed tides –

High tides (and low tides)

vary in height

Southeast Florida experiences semidiurnal tides.

Bay of Fundy: At the peak of the flood, water rises 1 meter (3.3 feet) in 23 minutes.

Tidal ranges are largest in the Bay of Fundy

(Nova Scotia, Canada).

This is partly because the Coriolis effect is

stronger, the closer you are to the poles.

Tides in the eastern Bay of Fundy on the

Atlantic coast of Canada. Tidal range is near

15 meters (50 feet). At the peak of the flood,

water rises 1 meter (3.3 feet) in 23 minutes.

Wave Action: Open Ocean

• Wave size, speed, and direction are controlled by winds

• The waves we see in the ocean are the result of wind energy

transferred to surface water

Wave action affects

only surface waters.

Motion decreases

downward to a depth

equal to about ½ of the

wavelength.

Wave Action

• Wind generated waves increase in size with increased wind

− Wind speed and distance over which wind blows (called fetch)

determine the frictional force, and ultimately the wave height

− Large waves come from high velocity, steady winds blowing

across a wide area with no obstructions

Which ocean do you think has consistently taller waves:

the Atlantic, or the Pacific? Why?

Where do you think the largest waves (5-10 m) on Earth

are found?

Southern Ocean – no continents to interrupt the

distance over which winds blow.

Wave Action

As a wave

approaches

shore and

shallower water,

it is slowed by

friction and its

length

decreases,

becoming taller

and steeper.

Wave eventually

collapses due to

gravity.

The amount of wave energy is influenced by stormy seasons

across the globe. For example, the West Coast of the U.S.

receives higher wave energy (in general) compared to the East

Coast after storms in Alaska generate waves that move across the

large Pacific Ocean, during the winter. See next two slides for

difference in beaches (winter wave energy carries sand offshore).

La Jolla, California – Summer Conditions

La Jolla, California – Winter Conditions

Wave Action

Rip Currents – Narrow currents of water flowing through gaps in

sandbars lying just offshore.

Rip currents are caused by variations in the surf zone such as

sandbars and channels.Do you see a location in the

picture at right that might be

dangerous if you were

swimming there? Do you

think you could see it from

the beach?

Rip currents cause ~100

deaths in the U.S. each year

If you get caught in one – let

it sweep you out past the

structure that is causing it.

Once past it, swim parallel to

the beach and then back

toward shore.49

Wave Action: Turning waves into energy

• Waves move energy, not water mass

• If that energy could be harnessed, it

would be clean and renewable

What is the best location to build an

ocean wave-driven power

generation facility?

What problems might you face? 50

Shoreline Features

What do waves do to coastlines?

• Cause erosion (wearing away headlands and filling in

bays – straightens out coastline)

• Transport material

• Deposit sand and other materials

Twelve homes in Pacifica,

CA were condemned when

the cliff retreated 33 feet.

Sea levels also impact the shape of coastlines.

About 18,000 years ago,

during the last ice age, sea

level was much lower. The

position of the gently sloping

southeastern coast was as

much as 200 kilometers (125

miles) seaward from the

present shoreline, leaving

much of the continental shelf

exposed.

Uh-oh!

Conditions predicted under a

scenario of sea level rise of 5 meters

… to be continued next week …

Sea levels also impact the shape of coastlines.

Shoreline Features

Shorelines can also be experiencing deposition

• Shoreline grows in width with deposition of sediment

• Head-on currents carry sediment onto and off the beach, and may

deposit sand in sand bars off shore during storms

• Longshore currents transport sediment parallel to the beach in the

surf zone

Sand was moved left to right during a storm.54

The longshore current creates features like barrier islands.

http://dep.state.fl.us/coastal/habitats/estuaries.htm 56

Bar-Built EstuariesEstuaries: where

saltwater and

freshwater mix.

They are very

biologically productive

and are important for

many organisms to

reach adulthood, such

as shrimp in Florida.

Seagrass in estuaries

provides safe habitat

for juvenile shrimp,

where they can hide

from predators.

Shoreline Protection

Natural features that protect coastal residents of Florida

from erosion:

-Tall dunes behind beaches protect against large storms

-Wide, stable beaches absorb wave energy

-Exposed offshore sand bars absorb the force of breaking waves

-Coral reefs and mangrove forests

These features are not found at all beaches.

Humans can erect artificial barriers to help slow

erosion, but these features may speed up

erosion in other coastal locations.

Shoreline Protection

Groins – wall-like structures built perpendicular to

the shoreline as barriers to longshore currents

• Causes deposition on upcurrent side, but erosion on

downcurrent side

Miami Beach is a barrier

island, which naturally

changes in shape over time.

There, many groins are built

to try to stop this

(but end up causing more

erosion over the long term).

Biological Oceanography

Images from Puget Sound:

M. Guannel/H. van Tol 60

Question:

Why do phytoplankton

have so many different

structures?

(Why are there so many

kinds of phytoplankton?

Ernst Haeckel

diatoms

Diatom drawings by Ernst Haeckel

Diatom art –

under a microscope

61Phytoplankton (plant like) –

autotrophs in photic zone.

Diatoms (a type of phytoplankton) inspire art.

Phytoplankton vary widely in size.

Finkel et al. 201062

Phytoplankton vary widely in size.

Finkel et al. 201063

Prochlorococcus and Synechococcus

are cyanobacteria, similar to the first

oxygen-producing life forms. Karenia brevis forms harmful

algal blooms in Florida.

Emiliana is a coccolithophore,

which forms sedimentary rock

like the White Cliffs of Dover.

Pseudo-nitzschia present (ARISA*)

* Automated Ribosomal Intergenic Spacer Analysis

Satellite-derived chlorophyll data (mg chl / m3)

Pseudo-nitzschia were detected in open ocean and coastal waters.

What are these two

regions called?

Pseudo-nitzschia present (ARISA*)

* Automated Ribosomal Intergenic Spacer Analysis

Satellite-derived chlorophyll data (mg chl / m3)

Pseudo-nitzschia were detected in open ocean and coastal waters.

What are these two

regions called?

Upwelling Zone

“Red Tide”:

Sometimes red, never a tide.

It is an accumulation of

microscopic algae

(usually dinoflagellates)

The more accurate term is

harmful algal bloom (HAB).

Karenia brevis causes

most Florida HABs.Why are red tides harmful?

Many red tides produce toxic chemicals

that can affect both marine organisms and

humans. The Florida red tide organism, K.

brevis, produces brevetoxins that can

affect the central nervous system of fish

and other vertebrates, causing these

animals to die. Wave action can break

open K. brevis cells and release these

toxins into the air, leading to respiratory

irritation. For people with severe or chronic

respiratory conditions, such as

emphysema or asthma, red tide can cause

serious illness. The red tide toxins can also

accumulate in molluscan filter-feeders such

as oysters and clams, which can lead to

Neurotoxic Shellfish Poisoning in people

who consume contaminated shellfish.

http://myfwc.com/research/redtide/faq/

Ocean Eutrophication & Dead Zones:

another way that algal blooms cause harm

http://www.tcpalm.com/opinion/guest-columns/richard-baker-indian-river-

lagoon-may-be-close-to-becoming-a-dead-zone-2e03ca8e-2862-50e9-e053-

01000-374618771.html69

Prochlorococcus

Prochlorococcus is so far the

most abundant photosynthetic

organism on Earth

(100 million cells in one liter of

seawater, from the open ocean)

This genus alone carries out

10-20% of all photosynthesis

in the ocean … and yet it was

only discovered about 30

years ago.

Photosynthetic bacteria

1985: Prochlorococcus was discovered by Dr. Sallie (Penny) Chisholm

of MIT and her postdoctoral researcher, Dr. Rob Olson.

2013: Dr. Chisholm received the National Medal of Science

(the nation’s highest award in science and engineering)

https://www.youtube.com/watch?v=m_43nR11PW8

Videos by Dr. Durkinhttps://cdurkin.mlml.calstate.edu/index.php/videos/

In-Class Activity: The Biological Pump –

Watch this video and observe what you see.

In-Class Activity:

What do you notice?

Note: the correct plural form of octopus is “octopuses”73

Corals have symbiotic relationship with

zooxanthellae, which are a type of

dinoflagellate.

Corals provide safe environment,

source of CO2 & nutrients.

Corals are invertebrate

animals, inhabited by

phytoplankton.

Zooxanthellae provide corals with oxygen,

carbohydrates and

alkaline pH to enhance CaCO3 deposits.

75Limestone

Animations and videos related to

the atmosphere and hurricanes

https://media.pearsoncmg.com/bc/bc_0media_geo/interactiveanimatio

ns/noqzs/042_GlobalWindsHC_HS_GG_Ins.html

Global Atmospheric Circulation animation:

https://www.youtube.com/watch?v=qh011eAYjAA

Global Air Circulation (clouds and water vapor = white; precipitation = orange):

http://media.pearsoncmg.com/ph/streaming/esm/atmospheric_science/wim/

wim_video.htm?wim=2005HurricaneSeason

2005 Hurricane Season: (takes some time to load)

http://video.nationalgeographic.com/video/101-videos/hurricanes-101

Hurricanes 101:

For the end of the in-class activity,

watch all four animations and videos

and take notes on the major points.

Chapter 14: The Atmosphere

Chapter 15: Weather

(we will only focus on hurricanes)

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