OSX-1005 tom lectures

Question 1

what is earth the only planet on the solar system to have on it’s surface

Answer 1

liquid water

Question 2

what % of the earth’s surface is covered in water

Answer 2

71% of the earth’s surface is covered in water

Question 3

where is the oceans water stored

Answer 3

96% in oceans 
2.9% in ice and snow 
1.0% underground water 
surface water 0.02% 
atmosphere 0.001%

Question 4

how is river input in the northern hemisphere compared to the southern hemisphere

Answer 4

river input is larger in the northern hemisphere compared to that of the southern hemisphere

Question 5

does melting of sea ice cause sea level to rise

Answer 5

melting of sea ice does not cause sea levels to rise due to Archimedes principle

Question 6

name two factors that cause sea levels to rise

Answer 6

addition of extra water to the ocean

warming of the ocean

Question 7

how can extra water be added to the ocean

Answer 7

by the melting of land ice

Question 8

how does the warming of the ocean cause sea levels to rise

Answer 8

warmer water is less dense than cold water as the same mass of water occupies a larger volume
so sea levels rise

Question 9

what is the oil and gas we burn today

Answer 9

the oil and gas we burn today is carbon that has been fixed by ancient plankton

Question 10

what is the current CO2 concentration in the atmosphere and how much has it risen by the last 50 years

Answer 10

currently 400ppm

risen by 85ppm in the last 50 years

Question 11

what would the atmospheric CO2 concentration be without ocean biology

Answer 11

it would be 200ppm higher without ocean biology

Question 12

what is the average depth and max depth of the Atlantic ocean

Answer 12

average depth 3330m

max depth 9144m

Question 13

name 3 special features of the Atlantic ocean

Answer 13

stretches from the arctic to the Antarctic
the gulf stream/ Atlantic gyres
gulf of Mexico / Caribbean sea(2% sa)
Extensive continental shelf seas

Question 14

what is the function of the gulf stream

Answer 14

it carries heat across the atlantic

warming the atmosphere

Question 15

what do the ocean currents link

Answer 15

the oceans current link the ocean basins(thermohaline circulation)

Question 16

what is the role of the ocean during storms

Answer 16

the ocean is a major heat source powering storms

Question 17

what is specific heat capacity of water

Answer 17

the energy required to raise the temperature of 1kg of water by 1 degrees Celsius

Question 18

what is thermal expansion of sea water

Answer 18

as seawater is warmed it expands
so the same mass occupies a greater volume
so density decreases as sea water is warmed

Question 19

how will a change to salinity affect sea water density

Answer 19

it will change the density as it changes the mass in the same volume

Question 20

name 3 ways you can change the salinity of sea water

Answer 20

add fresh water
formation of sea ice
evaporation

Question 21

what is a gravity

Answer 21

a natural phenomena by which objects attract each with force proportional to their masses

Question 22

how does the moon’s gravitation act on the earth

Answer 22

the moon’s gravitation force on earth acts on all parts of the earth

Question 23

what is the strength of the gravitational force proportional to

Answer 23

the strength of the gravitational force is proportional to the inverse square of the distance of the moon

Question 24

where will the ocean bulge

Answer 24

directly under the moon where the earth-moon distance is shortest and so force is strongest

Question 25

why are there two tides in a day

Answer 25

moon gravity 1st bulge

centrifugal force 2nd bulge

Question 26

where are tide’s formed

Answer 26

where there is a significant difference in the moon’s gravitational attraction