Ocean Atmosphere Interactions

Question 1

Ocenan + atmosphere

Answer 1

• Intimately connected through:
  -exhcange of water
  -gas exchange
  -energy transfer
• This interaction:
  -controls sea surface temp
  -moderates earth’s weather and climate
  -creates waves and currents

Question 2

Composition of the atmosphere

Answer 2

Nitrogen (78.1%), oxygen (20.9%), CO2, Argon, O3

Question 3

Greenhouse effect

Answer 3

• the Earth’s heat blanket
• Incoming sunlight is converted from visible light to radiated heat, which is in the longwave spectrum
• greenhouse gases work as a heat trap for the outgoing infrared (IR) radiation
• some of that heat is re-radiated as infrared radiation from the Earth is absorbed by the greenhouse gases ____

Question 4

Ozone layer

Answer 4

• upper atmosphere works as a filter for incoming ultraviolet radiation

Question 5

Vertical structure of the atmosphere

Answer 5

weather we experience is in the troposphere and tropopause
[pic]

Question 6

Atmospheric circulation - what are the main ingredients that affect atmospheric circulation?

Answer 6

• energy from the sun (the engine)
  -global distrubution of solar heating is uneven due to: seasonal variations, angle of sun over horizon, transparency of atmosphere, local reflectivity
• Earth’s rotation (the modifier)

Question 7

Solar energy distribution

Answer 7

• solar heating is uneven in a spherical planet
• diffuse radiation at high latitudes
• Concentrated radiation at low lats
• seasons are caused by tilt of the earth’s axis by 23.5 degrees, heating is uneven seasonally
• [pic]

Question 8

Why are the polar regions cold?

Answer 8

• solar insolation/area is lower at poles (energy spread out over larger area)
• more attenuation through atmosphere
• higher albedo in polar regions: more reflected energy

Question 9

Albedo

Answer 9

percent of solar radiation reflected back to space
reflectviity of earth’s surface
contributes to keeping the earth cool
average for earth = 30%, ice sheets = 85%, oceans = 7%

Question 10

Why does abedo vary with latitude?

Answer 10

Abedo is a function of:
* angle of incidence (oblique angle more reflected)
* surface type (ice, snow, water, soil, clouds, etc)

Question 11

Positive feedback: sea ice-abedo positive feedback

Answer 11

positive feedback: increases the intial change
negative feedback: reduces or counteracts the initial change
[pic]

Question 12

Many important climate feedbacks between ocean and atmosphere

Question 13

Heat budget as a function of latitude

Answer 13

Variations in heat recieved vs re-radiated at different latitudes
* the heat engine of atmospheric circulation
* this imbalance is compensated by ______

Question 14

Uneven heating leads to ..?

Answer 14

vertical and horizontal air movement
net transport of heat from warm to cool regions

Question 15

Evaporation/precipitation also play a role in transporting (redistributing) heat

Answer 15

Where water vapor is forming: absorption of latent heat
where water vapor condenses: release of latent heat

Question 16

Vertical air moevment

Answer 16

• air expands when heated, becomes less dense, and rises
• it keeps rising until it reaches the same density –> level of neutral buoyancy
• when the air cools it contracts and sinks again

Question 17

Horizontal air movement

Answer 17

air flows from high to low pressure
uneven solar heating –> areas of high & low pressure (density)
–> a force (the pressure gradient force) that drives the air from high to low pressure
(air does not always go in the direction of this force)

Question 18

Global air circulation

Answer 18

On a fictional, non-spinning Eath: a simple cell on each hemisphere, drivem by the pole-to-equator pressure gradient force
But on a rotating planet…

Question 19

The Coriolis “force”

Answer 19

• Critical to atmospheric and ocean cirulation
• due to the rotation of Earth on its axis
• deflects moving air or water from its initial course
  (to the rifht in the NH, left in the SH)
• deflection increases with latitude (no coriolis at equator, strong at the poles)
• acts over long timescale (10+ hrs) and long distances (1+ km)

Question 20

Movement on a rotating disk

Question 21

Coriolis force effects

Answer 21

• only changes the direction by deflecting to left/right, but does not change speed
• only has an impact on motions that are slow and travel over long distances
• important for ocean currents

Question 22

common misconceptions about coriolis force

Answer 22

• acts equally on motions to the north/south or east/west - wrong, deflects same amount in any direction
• not a real force, just an artifcat of looking at motion from a rotating reference frame

Question 23

Why do hurricanes spin CCW in NH but CW in SH?

Answer 23

• low pressure system surrounded by higher pressure
  *

Question 24

Atmispheric circulation on rotating earth

Answer 24

coriolis deflection on rotating Earth produces three circulation cells in each hemisphere
Note: coriolis does not cause the wild, it impacts the direction

Question 25

Surface wind pattenrs

Answer 25

• the bottom part of the three atmospheric ciruclation cells is what produces the global wind pattern
  Easterlies (trade winds and polar easterlies) go from east to west
  westerlies: go from west to east

Question 26

Intertropical convergence zone (ITCZ)

Answer 26

• warm air rises at the equator where the two hadley cells meet, causing low pressure in the tropics and a zone of ______

Question 27

Cloud formation

Answer 27

• a cloud is a parcel of air that contains condensed water
• the amount of water that air can hold depends on the mp
• as warm air rises it cools and water condenses to form clouds
• ____

Question 28

Wind belts, pressure systems, and weather

Answer 28

[pic]