emes final (exam 1 + 2)

what percentage of earth surface is covered by oceans

71%

what is the average depth of the ocean

4km

what is the average thickness of the atmosphere

100km

most to least abundant gasses in atmosphere

nitrogen, oxygen, carbon dioxide

what was concentration of CO2 prior to industrial revolution

290ppm

what is another name given to a latitude of 0 degrees

the equator

the distance equal to 1 degree of longitude

decreases from the equator to the pole

how are maps of earths surface distorted

1. dont preserve relative distances

2. dont preserve relative areas

3. dont preserve directions

what does vertical exaggeration in displays of ocean data look like

it makes vertical changes appear steeper than they actually are

express 1,000,000,000 in scientific notation

1.0x10^9

express 0.000001 in scientific notation

1.0×10^-6

early earth, soon after formation was:

hot with a molten surface

how long ago did life on earth first begin

3.6 billion years ago

what were the first forms of life

they were chemosynthetic

which form of -synthesis produces oxygen

photosynthesis

how many years ago was the peak of the last glacial maximum?

it was 20,000 years ago

how much cooler than the present were average global temperatures during last glacial maximum

10 C

is CO2 concentration in the atmosphere higher or lower during a glacial maximum

CO2 concentration is lower

what are two aspects of the ocean that make it difficult to work upon

1. waves

2. wind

why cant we “see” very far in water

because water absorbs light energy much better in air

atmospheric pressure:

decrease exponentially with height

pressure in the ocean:

increases linearly with depth

name two of the primary subdiciplines of oceanography

1. biological

2. chemical

what is the most common way at present to measure ocean bathymetry from a ship

sonar

name a device used to recover sediment sample from seafloor

grab sampler

what is the water column

is the water from the ocean surface to the seafloor

what is the name of the device used to collect discrete samples of water from a specific depth

niskin bottle

what vertical thickness of seawater equals the pressure of the atmosphere

10 meters

what is fouling

when something hard goes into the ocean, everything will stick to it

A CTD collects which types of information?

water temperature, depth and electrical conductivity

why is it difficult to collect samples of the biology of the ocean

the ocean is widely dispersed

what device includes a human operator inside of it

a submersible

name a method used to measure ocean currents

moorings

what is name given to earths innermost layer

the core

what is the physical state of the asthenosphere

it is plastic

name two types of crust on earths surface

oceanic and continental

the lithosphere is composes of the crust and:

composed of the crust and upper mantle

what force causes fluids to be layered from densest below to lightest on top

gravity and pressure gradient

what is a typical thickness of crust beneath the oceans

6-7km is typical thickness

when two oceanic lithospheric plates collide what determines which plate subducts?

whatever one is denser will subduct

what relative plate motion AND types of crust at that boundary give rise to coastal mountain range

covergent and oceanic-continental

what relative plate motion AND types of crust at that boundary give rise to mid ocean ridge

divergent and oceanic-oceanic

based on isostacy, what fraction of a floating solid with density 0.9g/cm³ would be ABOVE the surface of a fluid of density 1g/cm³

0.1

fraction submerged: 0.9/1.0 =0.9 submerged—> 0.1 left over not submerged

what is a hotspot

a region of much greater heat flow from the mantle toward the surface

name a hotspot

Hawaii. Yellowstone, galapagos

is west coast of South America an active or passive margin

active

sea level was more than 100m lower around globe during last ice age, was this a eustatic or isostatic change in sea level

this was a eustatic change in sea level

what type of chemical bond holds most salt molecules together

ionic bonds

what is the strongest chemical bond

covalent bond

what is latent heat of fusion

the energy required to convert ice to liquid water

what type of intermolecular bond gives water its amazing dissolving power

hydrogen bonds

what is the typical concentration of salts in seawater

35 PSU

what is the most common ion in seawater

chlorine is most common ion

a increase in salinity will cause what type of change in the density of seawater?

increase in density

a decrease in pressure will cause what type of change in density of seawater?

decrease in density

what is temp of maximum density of freshwater (containing no salts)

4 C

does the freezing point of seawater increase of decrease as salinity increases

it will decrease

does cold water hold more or less dissolved gases than warm water

it holds more dissolved gases

which colors of visible sunlight penetrates the deepest in pure seawater

blue or green

what is the smallest size of a sediment particle we discussed

clay and mud

does “well-sorted” sediments entering ocean have a narrow or broad range of particle sizes

they have a narrow range of particle sizes

most lithogenous sediments entering the ocean are presently derived from areas with:

derived from areas with steep topography

name a mechanism that transports lithogenous sediments which result in well-sorted sediment

rivers and wind

name a mechanism that transports lithogenous sediments which result in poorly-sorted sediment

landslides and glaciers

which two types of molecules are dominant in biogenies sediments

calcium carbonate and silicate

which molecule (calcium carbonate or silicate) tends to dissolve most readily in deep ocean

calcium carbonate dissolves most readily

what type of sediment is associated with hydrothermal vents

hydrogenous

do locations on seafloor with abundant manganese nodules have high or low sedimentation rates

low sedimentation rates

when do evaporite deposits form

form when dissolved substances precipitate out of solution

what is the typical sedimentation rate in the open ocean distant from the continents

1cm/1000 years

where is ocean sediment thickness greatest?

near coastlines on passive margins

why do we find calcareous sediments on the mid-atlantic ridge but not in the abyssal plains near Bermuda

calcium carbonate can not exist at great depth

how thick is the troposphere

it is 10km thick

what altitude is troposphere thickest

equator (0 degrees)

what happens if water vapor concentration exceeds the saturation vapor pressure

if it exceed its will rain

does warm air hold more or less water vapor than cold air

warm air holds more vapor than cold air

is water vapor more or less dense than primary components of air (oxygen and nitrogen)

water vapor is less dense than primary components of air

is surface air pressure high or low under warm rising air

surface air pressure is low under warm rising air

is surface air pressure high or low under cool rising air

surface air pressure is high under cool sinking air

name one of the major atmospheric features where persistent cloudiness is observed

the intertropical convergence zone (ITCZ)

does coriolis effect deflect flow (wind or currents) to the right of left in northern hemisphere

coriolis effect deflects flow right in northern hemisphere

what name is given to the east to west winds that are found within 30 degrees of the equator

trade winds

what latitudes would you find deserts

30N and 30S

why are deserts found at these latitudes

because air is sinking at these latitudes

what percentage of solar radiation impinging on earth reaches the ocean surface

50 percent of radiation

what is primary process that carries heat from the oceans back into the atmosphere

evaporative heat flux

what are two types of basic weather patterns

anti-cyclone and cyclone

where do extra-tropical cyclones form

they form at the polar fronts

why don’t tropical cyclones from in the tropical south Atlantic or tropical south east pacific oceans

they dont form because water is too cold here

what latitudes are sub-polar gyres found

found at 60 degrees N

what conditions of surface water in sub-tropical gyres

temps are high and nutrient concentrations are low

what conditions of surface water in sub-polar gyres

temps are low and nutrient concentrations are high

what is the warm pool

the place in the ocean with the warmest water

where is the warm pool found

found in the western equatorial pacific

ekman transport associated with the westerlies over the antarctic circumpolar current is in which geographic direction?

ekman transport would be north

how much do wind-driven currents typically extend in the ocean

these currents extend 1000m

do geostrophic currents flow parallel or perpendicular to contours of sea surface heights

these currents flow parallel to sea surface heights

would winds parallel to the coast, blowing toward the equator along the California coast cause upwelling or downwelling in coastal ocean

would cause upwelling in the coastal ocean

where are the two locations on earth where deep and bottom waters are formed

North Atlantic and near antarctica

the water column where deep waters from are expected to be weakly or strongly stratified?

deep waters are expected to be weakly stratified