chapter 4

Question 1

mesoscale circulation in tropics:

Answer 1

Diurnal variation of solar radiation and temperature are greater than annual variation

Question 2

mesoscale circulation in mid lat:

Answer 2

annual variation is greater than diurnal variation

Question 3

what causes land and sea breeze and mountain circulation

Answer 3

• land and sea boundaries and topography
  
  • cause differential diurnal heating
    
    • more pronounced in the tropics
    • initiate
      
      • mesoscale circulation
        
        • land sea breeze
        • mountain circulation

Question 4

from sea to land is called

Answer 4

land breeze

Question 5

Land sea breeze

Answer 5

• Difference in land sea breeze extend between tropics and mid lat

Question 6

land sea breeze is due to

Answer 6

• weaker corriolis acceleration in the tropics
  
  • can be explained by using rossby radius of deformation

Question 7

rossby radius of deformation is a measure of

Answer 7

• the effect of corriolis parameter (earth rotation) on circulation
• the ratio of gravity wave speed (c) to the corriolis parameter (f)

L=c/f = sqrt(gH)/2(omega)sin(o|)

Question 8

H is …….. and is proportional to …………….

Answer 8

equivelent depth

• stability
• the acceleration due to gravity

Question 9

……….. and ………. change from mid latitude to tropics

Answer 9

only H and o|

Question 10

Range of H in tropics:

Answer 10

(10-500m) 400 m > the value of H in mid lat (by order of 1 mag)

Question 11

compare Lr in tropics and midlatitude

Answer 11

• large in tropics
  
  • H is greater
  • o| is smaller
• small in mid lat
  
  • H is smaller
  • o| is larger

Question 12

calculate Lr where H is 400 m assume f=10^-5 s^-1

Answer 12

6300 km (radius of deformation)

Question 13

radius of deformation

Answer 13

if circulation smaller than the calculated value the corriolis have no effect

Question 14

tropics circulation ……………. than the radius of deformation ………………….

Answer 14

smaller

are not effected by that circulation

Question 15

Mid latitude circulation ……………. than the radius of deformation ………………….

Answer 15

is larger

limits the horizontal extent of the land sea breeze by turning the wind and thus limiting its inland or offshore influence

Question 16

what is mountain valley circulation

Answer 16

thermally forced circulation

Question 17

land sea circulation and mountain valley circulation is due to

Answer 17

• Land sea circulation:
  
  • due to differential heating induced by land water distribution (differences)
• mountain valley circulation:
  
  • due to differential heating induced by elevation differences

Question 18

Mountain valley circulation types

Answer 18

• upslope breeze (valley breeze)
• downslope breeze (mountain breeze)

Question 19

valley breeze (upslope)

Answer 19

• occur in after noon (as the solar radiation heats the surface)
• give rise to cloudiness over mountains
• maximum rainfall at around 1000 m above the valley floor
• rainfall decreases at teh foot or toward the top of the mountain (due to evaporation)

Question 20

mountain breeze (downslope breeze)

Answer 20

• occur at night
• clear sky over the mountains

Question 21

where convective clouds dominate:

Answer 21

• Rain fall is maximum at 1000m (convective clouds)
• rain fall decrease:
  
  • above: lack of moisture
  • below:
    
    • dont experience much orographic lift
    • evaporation of rain bellow the cloud base

where stratiform cloud dominate the maximum rainfall tend to occur near the top of the mountain

Question 22

Stress differential:

Answer 22

air flowing parallel to a coastline is subjected to more drag by land than by the sea due to abrupt change in friction

Question 23

cross isobaric angle large and small (graphs)

Answer 23

Question 24

the cross isobaric angel from o|

Answer 24

o|= C_D/F

C_D: drag coef

F: corriolis parameter

Question 25

o| depend on:

Answer 25

• cp: if Cd is more -> larger o|
• f: if f is small (low lat) –> larger o|

Question 26

the two sinarios where low is once to the right and once to the left (graph)

Question 27

Coastal influence in summer: (graph)

Answer 27

• stress differential (and induced div) overland
  
  • increase temperature gradient between land and sea which
    
    • strengthen summer monsoon circulation