the hydrosphere 1 Flashcards
how much of the earths surface does the ocean cover
71%
what controls the earths climate? and why?
oceans, due to high specific heat capacity
what regulates and maintain earths oxygen balance
oceans
order oceans from largest to smallest
pacific, atlantic, indian
order oceans from deepest to shallowest.
pacific, indian, atlantic
what are the 5 major forces which govern circulation on the ocean and atmosphere
gravity, pressure gradients, drag/ momentum gain or loss, Coriolis force, tidal motion
what causes differences in pressure?
differences in temperature, salinity and density
explain what happens with a greater pressure gradient
a greater pressure gradient means a larger pressure gradient force resulting in stronger winds and ocean currents
how does pressure move?
from high to low (in the absence of other forces)
wha is preseure gradient force
the horizontal acceleration of water or air due to pressure differences
what is the formula for PGF
difference in p/ distance
what is the coriolis force
force due to the rotation of the earth
what does the magnitide of the coriolis effect rely on
speed of the moving object and latittude
explain the coriolis effect inthe northern vs southern hemishpere
northern hemishpere; reflection to the right, counter clockwise. southern hemishpere reflection to the left, clockwise
what is geostrophic circulation
phenmenon the occurs when pgf and coriolis effect balacne each other out causing geostrophic flow or circulation
what couses tidal motion
interaction between earth and other members of the solar system sun and moon
what does momentum transfer and drag do
transfers momentum from the atmosphere to the ocean
topography of the ocean can be divided into 3 units
continental margins, deep ocean basin floor and mid ocean ridges
components of continental margin
continental rise, slope and self
deep sea floor topography components
abyssal plains, abyssal hills, oceanic rises, trenches and seamounts
layers of the ocean from top to bottom
epipelagic/sunlight zone, mesopelagic/ twilight zone, bathypelagic/ midnight zone, abyssopelagic/the abyss, hadal zone/ the trenches
what is salinity
amount of solid material per gram in 1kg of sea water
changes in salinity is due to
evaporation and precepitation
salinity maxima and minima are located where and why
maxima- in trade wind regions due to high evaporation
minima- near equator(high precepitation) near poles (absence of evaporation) formation of ice rejects salt, dense salt rich water sinks to bottom leaving surface water with low salinity
Sea surface temp results from
absorpbtion of incoming solar radiation/insolation
explaiint he relationship between sst and latitiude
the higher the latitude the lower the SST
rship between salinity and temp
the higher the salinity the lower the freezing point is
Average salinity and fresszing point
34.7 and -1.9 c
density
determines the depth at which water mass will settle in equilibrium
cold temps when it comes to salinity pressure and density
higher
warm temps when it comes to salinity, pressure and denity
lower
pycnocline zone
500-2000m deep when water salinity increases greatly, very stable area
deep zone
area under pycnocline zone whater density increases slowly
water mass
large volume of water where particales have similar geographic origin.
sound in water depends on what variables
temp, pressure and salinity
