What is the Mesoscale?

Question 1

For flow to be geostrophic, the Ordinary Rossby Number (advective) needs to be ____

Answer 1

small

Question 2

What is the equation for the Rossby Number?

Answer 2

R0 = U / Lf

where U = velocity of the fluid
L = horizontal length scale
f = Coriolis parameter

Question 3

R0 &laquo_space;1 for ____ flow

Answer 3

geostrophic (rotationally balanced)

Question 4

R0 is essentially a ratio of the ____ ____ and the ____ parameter

Answer 4

local acceleration (U/L) and Coriolis parameter

Question 5

Name 3 ways to make R0 larger?

Answer 5

1) decreasing the size of a system (decrease L)
2) decrease the latitude (decrease value of f)
3) Increasing the wind speed (increase U)

Question 6

A system is less likely to conform to geostrophic balance (larger R0) if? (3 things)

Answer 6

1) The system is small
2) A system is located at low latitudes (closer to the equator)
3) system contains strong winds

Question 7

Rw stands for what?

Answer 7

Wave Rossby Number

Question 8

What is the equation for Rw?

Answer 8

Rw = c / Lf

where: c = gravity wave speed
L = horizontal length scale
f = Coriolis parameter

Question 9

What is the Lr?

Answer 9

Rossby Radius of Deformation

Question 10

What is the equation for Lr?

Answer 10

Lr = c / f

c = gravity wave speed as a function of static stability (buoyancy) of the fluid
f = Coriolis parameter

Question 11

The Rossby Radius of Deformation is the horizontal scale at which ____ effects become as important as ___ effects

Answer 11

rotation | buoyancy

Question 12

When the scale of a weather system is ____, buoyancy dominates over rotation

Answer 12

smaller

Question 13

When the scale of a weather system is ___ than Lr, rotation dominates over buoyancy

Answer 13

larger

Question 14

When the scale of a weather system is smaller than Lr, this defines the ____, or smaller

Answer 14

mesoscale

Question 15

When the scale of a weather system is smaller than Lr, the ___field adjusts to the ____ field

Answer 15

mass | wind

Question 16

When the scale of a weather system is smaller than Lr, ____ ____ dominate over ____ ____

Answer 16

gravity waves | geostrophic flow

Question 17

When the scale of a weather system is larger than Lr, ___ ___ dominates over ___ ____

Answer 17

geostrophic flow | gravity waves

Question 18

When the scale of a weather system is larger than Lr, the ____ field responds to the ___ field

Answer 18

momentum (wind) | mass (height or pressure)

Question 19

The maximum size of the mesoscale is essentially whatever the ____ is at that Location

Answer 19

Rossby Radius of Deformation

Question 20

What are the Lr values of:

1) mid-lat convection
2) equatorial convection
3) near-equatorial convection
4) tropical cyclone

Answer 20

1) Lr ~ 300 km
2) Lr ~ infinity
3) Lr ~ 1500 km
4) Lr ~ 5 km

Question 21

____ ____ in a barotropic model is a product of rossby wave generation in the tropical upper troposphere

Answer 21

Tropical Plumes

Question 22

With a broad trough, (L ___ Rossby Radius), and ___ balance dominates over ___

Answer 22

L>Rossby Radius

rotational balance dominates over buoyancy

Question 23

With a contracting trough, L ___ rossby radius, and rotational and buoyancy ____

Answer 23

L~rossby radius

rotational and buoyancy equal

Question 24

With sharp trough, L __ rossby radius, ___ dominates over ____. A ___ ____ forms

Answer 24

L < rossby radius

buoyancy dominates over rotation

Tropical plume forms