1. Marine Biology
Chapter 8
Michael Slemp

2. Octopus Is cephalopod mollusc Octopuses have two eyes
8 arms with suction cups
Hard beak in the mouth
Octopuses have no internal or
external skeleton
One of the most intelligent of all invertebrates
To defend themselves, they release ink (melanin = same as your hair and eye color), use camouflage and arm autonomy (detaching of arm)
All octopuses are venomous
Short life expectancy (6months-5 years). Die shortly after reproduction
They have 3 hearts ( 2 pumps blood thru gills and 1 thru body)
They eat crabs, other molluscs (clams), fish, other cephalopods

3. What is AIR (atmosphere)?
Gases
Water vapor
Aerosol
Nitrogen 78 %
Oxygen 21 %
Argon 1%
Carbon Dioxide 0.03%
All other gasses 0.01%
See pie chart in your book page 8-4
Water vapors are invisible. The reason clouds are white is because the water have condensed
Aerosol is liquid and solid particles suspended in air (like dust, pollen, ash)
Water vapor and aerosol makes about 4% of air)

4. Atmospheric layers
Thermosphere: beyond 110,000 meters (360,800 feet) into space
Mesosphere: up to 100,000 meters (360,800 feet)
Stratosphere: up to 50,000 meters (164,000 feet)
Has the most ozone!
Troposphere: from sea level up to 15,000 meters (49,200 feet)
Contains most of the air. Air compresses under its own weight = higher air pressure

5. What is ozone? Gas composed of 3 oxygen atoms (O3)
Normally oxygen molecule has 2 oxygen atoms (O2)
Extra oxygen in ozone causes instability and increased reactivity
Ozone is mostly in stratosphere and absorbs the UV light (radiation from sun)
Ozone protect us. If there would be no ozone, the UV light would kill the life on our planet
In 1974, scientist came out with theory that ozone interacts with CFCs (chemical found in aerosols and air conditions)
Reaction of ozone with CFCs can cause ozone hole and effect life on planet Earth!
Scientists are monitoring the size of the ozone hole existing over Antarctica

6. How much water vapor is in the air?
That depends on temperature, density and pressure
As temperature increases, pressure increases and density decreases
Adding water vapor decreases air density even more
Air is denser than water vapors
Warm, moist air is less dense than cold air.
Two air masses of the same temperature can have different densities
It depends on the amount of water vapor
Air with more water vapor is less dense
Evaporation
Adds water vapors into the air
Condensation
Removes water vapors from the air

7. Saturated air
Air in which the rate of evaporation and the rate of condensation are the same.
The amount of water vapors is unchanged.
What happens when saturated air cools down?
There is increased condensation
Water vapors are removed from air in form of rain or snow (if temperature is low enough)
Initially water droplets or ice crystals are very small and remain suspended in air
As they collide, they form bigger drops or clusters or ice crystals. This lead to rain or snow
Rain and snow happens when warm moist air mass collide with cooler air mass
What happens when saturated air warms up?
It becomes undersaturated.
Evaporation adds more water vapors into undersaturated air.

8. Why is this important?
Air movements redistribute heat around the Earth
Precipitation is our main source of fresh water
All underground water, rivers, lakes get their water from rain and snow. They return water and nutrients back to the ocean

9. Earth’s heat balance
Sun is the major energy source for Earth’s surface
25%
20% absorbed by clouds and atmosphere 5%
25% reflected by clouds and atmosphere
20%
Atmosphere either absorbs or reflects 45% of sunlight
50% is absorbed by Earth’s surface
55% of sun’s energy reaches Earth’s surface
5% is reflected by Earth’s surface
50%

10. Earth’s heat balance
At any time, only half of the Earth’s surface receives sunlight
(makes day and night)
The energy coming to earth is ultimately lost as heat radiating back into space

11. UV light (ultraviolet light)
What is solar energy?
UV light (ultraviolet light)
Visible light
Infrared light
Makes it through the atmosphere to Earth with little absorption
Is absorbed mostly in stratosphere by the ozone layer
Some is absorbed by carbon dioxide and water in stratosphere and troposphere

12. Unbalanced energy = Earth gets hotter, less likely we survive!
Earth’s heat balance
Solar Energy is reflected from various surfaces like
clouds
atmospheric particles
snow
reflective objects on Earth’s surface
ALBEDO
The measure of amount of energy something reflects
Snow has high albedo
Black sand has low albedo
To maintain balance between incoming energy from sun, eventually all energy Earth absorbs reradiates through various paths back to space as infrared radiation
Unbalanced energy = Earth gets hotter, less likely we survive!
Yellow = reflection, red = absorption
Left arrow – snow, right arrow -water

13. Greenhouse effect Important for life on Earth
Atmosphere, after it absorbed infrared radiation, reradiates a lot of the heat back to Earth’s surface
Most of the heat is collected in troposphere and stratosphere layers
Without Greenhouse effect Earth would be on average 35°C (95°F)
The concern is that increased carbon dioxide and other heat-retaining gasses will cause global warming and increase the overall temperature on Earth!

14. Uneven Heating
If there would be even heating on earth, there would be little changes in temperature and no seasons
But we know that there are seasons and temperature changes
There are 3 primary factors that cause the Earth to heat unevenly:
Earth is spherical
Earth’s axis of rotation is tilted
Distance between Earth and sun varies with the time of the year

15. Uneven Heating Earth is spherical
In order to be perpendicular rays, they would have to come from this direction, which does not happen in this area!
Earth is spherical
Small part of sphere receives perpendicular light rays (mainly in areas around equator)
Most of the sphere receives slanted light rays
These slanted rays have same energy but got to cover larger area (means less energy per area unit)
The farther North and South you go, the more slanted the sunlight reaching the surface
Slanted rays
Perpendicular rays

16. Uneven Heating Earth’s axis of rotation is tilted
Earth does not spin with its axis perpendicular to the plane of its orbit
Earth’s orbit inclines 23.5 degrees off
Equator does not always receives perpendicular rays from the sun
Depending on the time of the year, perpendicular sun rays fall anywhere between the Tropic of Cancer (23.5° north latitude) and Tropic of Capricorn (23.5° south latitude)
Longest day of the year for each hemisphere is when the sun is directly overhead at the Tropic line

17. Uneven Heating Earth’s axis of rotation is tilted
The Amount of sunlight falling on different parts of Earth changes and creates seasons
When the Earth is tilted with North Pole toward the sun = there is summer in North hemisphere (and winter in South hemisphere)
When the Earth is tilted with North Pole away from the sun = there is winter in North hemisphere (and summer in South hemisphere)

18. Uneven Heating Earth’s orbit is not circular
Earth’s orbit is slightly elliptical
Earth gets more heat when its orbit brings it closer to the sun
Earth is closer to the sun during winter in North hemisphere and farther away from the sun during summer in North hemisphere
This explains why North hemisphere has warmer winters and cooler summers than South hemisphere

19. Uneven Heating Biological Importance
Based on seasons we can predict migratory patterns
Gray whales annually migrate to Arctic waters to feed off blooming krill and plankton in summer
In winter gray whales swim south to breed in warmer waters around the Mexican Baja Peninsula

20. Uneven Heating Convection
Convection is vertical movement of currents caused by temperature differences in a fluid (like air)
On Earth, equator is the “kitchen stove” warming up all the Earth’s air and the poles are the cold parts.
Equator: air heats up and rises, travels towards the poles
Poles: Air cools down and sinks, and moves back towards equator where it replaces warm air
Solar energy absorbed by Earth surface causes a general global pattern of winds moving air between equator and poles
Sun warms up Earth
Earth warms up air in contact with it
Warm air is less dense and raises
High above, warm air cools down and becomes denser (moves down towards the Earth surface)
Cold air replaces warm air (and cycle continues creating circular pattern)

21. Is the tendency for the path of a moving object to deflect
Coriolis effect
Is the tendency for the path of a moving object to deflect
To the right on the Northern hemisphere
To the left on the Southern hemisphere
Coriolis effect
Explains why we have winds in all directions, not just from north or south
Effects also the ocean currents
Is major factor affecting the distribution of the Earth’s heat, nutrients and many types of life
Is caused by Earth’s rotation
Is greater at higher latitudes
Is zero at equator because the rotational velocity does not change

22. The wind
Recall
Convection causes general circulation pattern that moves air between the equator and the poles
The Coriolis effect deflect air to the right as it travels (to the left in the southern hemisphere)
This gives the air circular flow pattern rather than a straight north-south pattern
It is not as simple as above!
Wind patterns exists in small regions called atmospheric circulation cells
Atmospheric circulation cells are six distinct air masses (3 in each hemisphere) with individual airflow patterns

23. The wind – 1. Hadley cells Most important atmospheric circulation cell
They lie between the equator and 30 degree north or south latitude
Warm air rises at the equator and moves northward due to convection
Air does not make it all the way to the north pole
By the time it reaches 30°N it becomes dense enough from cooling and moisture loss to sink
Most of the air descends and flows back to the equator, deflecting to the right (westward) as it flows
This causes trade winds (flow westward between equator and 30° latitude
Trade winds are what brought ships to Europe and America centuries ago

24. The wind – 2. Ferrel cells Between approximately 30-60 degree latitude
These cells exist because some of the wind that descends from Hadley cells does not turn toward the equator
They continue towards the poles shifting to the right or left (depends on the hemisphere)
The airflow forms the westerlies (because they are from the west) and blows towards the east
The vertical circulation in Ferrel cells is opposite of what you would expect from convention because it is “sandwiched” between the Hadley cells and the Polar cells

25. The wind – 3.Polar cells
These lie between approximately 60 degrees and the pole
Airflow in the polar cell is similar to the Hadley cell
Warm air at 60 degree rises and flows towards the pole, where it cools, descends, and flows back to the equator
Coriolis effect deflects it, so that the prevailing polar winds go to the west
The south –flowing cold air from the polar cells affects the air flowing north and eastward in the Ferrell cells.
Two air masses do not easily mix due to the different densities and temperatures.
Polar cell air rises and heads northward again from convection, and causes the Ferrell cell air to deflect upward

26. INTERTROPICAL CONVERGENCE ZONES
This is where the trade winds meet from both hemispheres
30 degrees north and south latitude
Trade winds rise in this region
Vertical movement of air in ITCZ transports large amounts of heat and moisture
Water vapor condenses in the rising and cooling air, and rainstorms form.
Some of the world’s wettest climates are in the ITCZ
Surface winds are weak
Sailors call this area doldrums because they could be stranded there without winds
ITCZ influences climates and weather, and the seasons and landmasses affect the ITCZ

27. INTERTROPICAL CONVERGENCE ZONES
This is the reason why there is a difference between the geographical equator and the meteorological equator (ITCZ)
Geographical equator is 0 degrees latitude
ITCZ is an imaginary line marking the temperature equilibriums between the hemispheres that shift North and south with seasonal changes.
It shifts because land has lower heat capacity than water, and there is more land mass in the northern hemisphere.
Not a straight line due to the landmass affects its location
The ITCZ equator is important because atmospheric circulation is approximate symmetrical on either side of it
30 degree latitude leads to high evaporation and little rain fall
Most of the earth’s desert are at this latitude
There is a higher salinity around 30 degree latitude
More water is evaporated that returns to the ocean making a higher salinity concentration

28. Monsoons
Seasonal wind pattern changes caused by heating or cooling on the continents
Causes summers with significant rainfall and winters with very little
Results when air warmed by a hot landmass rises
Warm, moist air from the ocean flows in to replace it; this in turns also rise
Cools, which causes rain
When winter comes the cycle is reversed
Wind reverses and land has very little rain
Common in India and southeast Asia

29. Cyclones
Large rotation storm systems of low pressure air with converging wind at the center
Also called typhoon or hurricanes
Two types: extra tropical and tropical

30. Cyclones - Tropical From within a single atmospheric cell
Form in low latitudes
Experience explosive growth because of extremely rapid transport of heat and moisture into the atmosphere from the surface of the warm, tropical ocean
They quickly dissipate once they hit land due to the loss of heat
Cyclones move tremendous amounts of heat from the tropics to higher latitudes very quickly
One cyclone can release about as much energy as the USA uses in an entire year
This redistribution of heat is important to life on earth

31. Cyclones - Extratropical
Form in higher latitude
Forms as an area of low air pressure intensifies
Occurs between the westbound polar winds and eastbound westerlies
These do not become hurricanes or typhoons
They do cause hurricane strength winds, huge ocean waves rain and snow outside the tropics