Dynamics Exam 2 Review Flashcards
Coriolis Acceleration
-dependent on Earth’s rotation (Omega does not equal 0)
-only present in motion relative to Earth’s exits (v does not equal 0)
-force acts only at right angles to the velocity therefore can only change direction not speed
An ________ in the _________ direction due to the Coriolis Force can occur when motion _____ to earth occurs in the _________ or ________ directions
Acceleration, zonal, relative, meridional, vertical
East ward motion (u>0) generates _______ centrifugal force relative to that due to earths _______ alone. This leads to an upward an _________ acceleration (dw/dt)>0 and (dv/dt)<0 we label this as an effect of the __________. Likewise, with ______ motion (u<0) results in an overall ______ of the centrifugal force causing a ______ and poleward acceleration.
Excess, rotation, equatorward, Coriolis force, westward, deficit, downward
How is the flow in Inertia circles?
Completely Horizontal
What is the only force present in inertia circles?
Coriolis Force
Will get _______ nearly circular motion not exactly a circle
Anticyclonic (CW)
The faster you go the greater the__________
Distance travelled
Pressure Gradient Force (P.G.F)
-Driving force for the winds
- a force that acts from high pressure regions towards low pressure regions in the atmosphere
PGF qualities (more in depth)
A vector quantity with a preferred direction
-atm pressure itself is a scalar quantity; in fact, atm pressure is isotopic in all directions at a point in space
Horizontal and vertical pressure _______ generate a ______ which when acting by itself accelerate air parcels from _______ to _______ pressure regions
Difference, force, high, low
Higher ______ weaker ______
Density, pgf
Lower______ stronger _____
Density, pgf
Force of Friction
Acts to resist motion; represente in vector form; acts opposite to the flow
Friction due to molecular “viscosity” of the air
Important only at the surface
Friction due to “turbulence”
Sheared flow, and convective motion due to uneven heating
Sheared flow
Turbulent motion mixes momentum eliminating the shear
Convective motion due to uneven heating
Convective turbulence
Turbulent motion typically occurs in the _______________________
Planetary Boundary Layer (PBL) only
Planetary Boundary Layer (PBL)
The part of the troposphere that is directly influenced by the presence of the Earth’s surface
Eulerian system of equations
-equations are formulated in terms of partial (local) time derivatives
-changes due to advection explicitly appear on the right hand side of the equation
Numerical Weather Prediction (NWP) model is an example of what type of system of equations?
Eulerian
Lagrangian System of Equations
-equations are formulated in terms of total time derivatives
-isolating an air parcel, examining changes as parcels moving through space
Air Pollution Trajectory Model is an example of what type of system of equations?
Lagrangian
Hydrostatic Balance
-vertical component of the pgf balancing the gravitational force
Geostrophic Balance
-horizontal component of the PGF balancing the horizontal component of the Coriolis Force
Divergence is associated with the _______ part of the flow
Ageostrophic
Gradient Balance
A force “balance” between the pressure gradient force and a centrifugal force
Gradient Wind
Theoretical wind that results from gradient balance; a wind that flows parallel to curved isobars at a constant speed; direction changing therefore accelerated flow
Cyclostrophic Balance
A balance between the horizontal pressure gradient force and the centrifugal force; representative of small scale curved flow associated with high wind speeds an phenomenon at low latitudes (tornadoes, dust devils, eye-wall circulation of hurricanes)
Rossby Number
The ratio of the acceleration due to the centrifugal force to that due to the Coriolis force
