oceans exam 2

terrigenous

The weathered remains of continental rocks moves from land to see

terrigenous comes from

comes from rivers wind, Saharan dust, volcanic dust and glaciers

Biogenous

The remains of marine life

where does biogenous come from?

calcareous ooze and siliceous ooze

heterogeneous

Minerals out of seawater

calcareous ooze

made of calcite. uncommon in deep and cold deep water

hyrogenous comes from

Seawater

Polymetallic nodules

Type of hydrogenous sediment usually found in areas with low amounts of other sediments

Cosmogenous

Material from space

why is marine sediment significant?

climate regulation and scientific value

sediments affect on climate regulation

The oceans are a major part of the Earth carbon dioxide cycle

Scientific value of marine sediment

within sediments, we can find a clue to ancient oceanography in atmosphere conditions

average shelf pressure

13 atmosphere

average abyssal plains

500 atmospheres

deepest trench pressure

1100 atmospheres

at 1 m how much of light is absorbed

60% light

a 10 m how much light is absorbed

80%

at 100 m how much of light is absorbed

93%

at 1 km how much of light is absorbed

100% of light is absorbed

which light is absorbed first

heat

what light is absorbed second

Red and ultraviolet

what light is absorbed last?

Blue light

High frequency

Absorbed quickly

Low frequency

Travels farther

SOFAR layer

The zone of minimum stand velocity, but greatest efficiency

What is the freezing point of seawater?

28°F

Sea ice forms..

directly from frozen seawater in the same way ice forms on a lake

Iceberg’s form…

From glacial ice, which forms from compressed snow

pinnacle iceberg

Mainly from small glaciers. The most common.

tabular iceberg

massive flat top arctic continental glaciers

what is salt in the oceans?

Everything in the ocean, other than carbonate and organic materials

salinity

Total quantity of dissolved in organic material in water

what is the average salinity of the ocean water?

35PPT

what causes salinity to decrease?

Heavy rainfall, major, rivers, ice, melting

what causes salinity to increase?

High evaporation rates, isolation

how does salinity change with latitude?

30° latitude have higher salinity. Around the equator and around 60° latitude salinity decreases.

what are the major gases in the ocean?

Nitrogen, oxygen, carbon dioxide

nitrogen

Enters the ocean, mainly by atmosphere gas exchange

oxygen

Enters through the atmospheric exchange and life

carbon dioxide

Enters partially by atmosphere, but also under sea volcanic activity and life

what are the three major layers of the ocean?

surface zone, pycnocline, deep zone

surface zone

uppermost zone. Temperatures in salinity are relatively constant from top to bottom within this layer due to wind waves and surface currents

pycnocline layer

Transitional zone density increases sharply in increasing depth, not present in higher latitudes

the deep zone

below pycnocline, starting below approximately 1000 m.

thermohaline circulation

cold water tends to sink beneath the warmer water. Higher salinity sinks below, lower salinity water.

Antarctic bottom water (AABW)

Deepest dens and coldest water. Forms approximately 60° latitude near the coast of South America and flows to the north.

north Atlantic deep water (NADW)

forms in the Arctic ocean and flows south. Pretty cold, but not as cold as AABW.

antarctic intermediate water (AAIW)

A somewhat warmer mass of water that forms in southern latitudes

mediterranean outflow (MOW)

saltier but warmer than other currents so it’s less dense. It is found above the north Atlantic deep water and flows west

pressure gradient force

The driving force of wind. affects wind direction. Wind blows from high pressure towards low pressure.

Coriolis effect

Because the Earth rotates, the wind can’t go in a straight line so it appears to curve

High pressure winds flow…

Outward and clockwise

Low pressure winds flow…

Inward and counterclockwise

Tradewinds

East to West (warm)

prevailing westerlies

West to east (yellow)

polar Easterlies

East to West (cold)

The intertropical convergence stone

Low pressure zone circulating the Earth near the thermal equator

coastal deserts.

Where cold water continuous leak circulates near a coastline local humidity is greatly decreased, lowering cloud formation in precipitation

offshore breeze

wind blows from the land to the water (land is cooler)

onshore breeze

wind blows from the water to the land (land is warmer)

monsoon

seasonal wind patters- not storms as commonly believed.

summer monsoon

brings in large amounts of rain to india. the coriolis effect causes these up winds to be deflected to the northeast, so southeast asia is affected

winder monsoons

india cools and acts as high pressure.wind blows from the land to the ocean, so the rainy season ends and dry conditions take over

where do monsoons happen

india, west central africa, southwestern north america, northern gulf/southern US