Which 5 forces explain all relationships between the winds we observe and the patterns of isobars/height contours on weather maps?
Gravity, Coriolis effect, friction, pressure gradient force, centripetal force
_________ air wind are parallel to isobars while _____________ winds go at different angles to isobars.
Upper, surface
Pressure gradient = change in ____________ over change in _____________
pressure, distance
Air goes from _________ to _________ pressure.
high to low
The Coriolis force causes winds to deviate __________ in the northern hemisphere, ________ in the southern hemisphere and _____________ at the equator
right, left, not at all/none
The Coriolis force is more exaggerated at _______ __________ __________ or closer to the __________
higher winds speeds, equator
The force of friction increases with 2 things :
movement (wind speeds) and the roughness of surfaces (the Earth)
What are the two types of momentum exchange? Which is has more dramatic effects on Earth?
The random movement of molecules in laminar flow and eddies, eddies are more dramatic
Momentum due to eddies transfers the effects of friction higher into the atmosphere and produces _______ ________________ which we experience as _______
eddy viscosity, wind
The effects of friction transfer better with what 3 things?
high wind speeds, lots of surface roughness, and lots of surface heating
What 3 things work to increase the planetary boundary layer?
rough surfaces, fast winds, unstable environmental lapse rate
What is the correct order?
- feedback processes
- balanced forces
- Air moves from high to low pressure (pressure gradient force)
- other forces take action
- Air moves from high to low pressure (pressure gradient force)
- other forces take action
- feedback processes
- balanced forces
What are the 3 types of winds we discussed?
Geostrophic winds (Vg), Gradient winds (Vgr), and surface winds
Geostrophic winds happen (above/below) the planetary boundary layer because _____________ is negligible there.
above, friction
Regarding geostrophic winds, what is happening after the first step in this timeline (ie, what forces are taking action?, what feedback processes are happening? what does it mean when the forces are balanced?)?
Air moves from high to low pressure (pressure gradient force) ---> other forces take action ---> feedback processes ---> balanced forces
Air moves from high to low pressure (pressure gradient force) ---> Coriolis force takes action ---> feedback processes (continuous changing of direction) ---> balanced forces (wind parallel to isobar because PGF and CF are equal)
Regarding gradient winds, what is happening after the first step in this timeline (ie, what forces are taking action?, what feedback processes are happening? what does it mean when the forces are balanced?)?
Air moves from high to low pressure (pressure gradient force) ---> other forces take action ---> feedback processes ---> balanced forces
Air moves from high to low pressure (pressure gradient force) ---> centripetal force and Coriolis effect take action ---> feedback processes (PGF, wind speed, Coriolis force and centripetal force if isobars are curved) ---> balanced forces (net force is being directed at centre of rotation, wind parallel to isobars)
Why does wind deaccelerate coming out of a ridge? Why does it accelerate coming out of a trough?
converges (like a pileup on the highway), diverges to fill a void (lots of space for it)
In the upper atmosphere gradient winds affected by areas of high pressure extend ________ and areas of low pressure extend _______
north, south
Regarding surface winds, what is happening after the first step in this timeline (ie, what forces are taking action?, what feedback processes are happening? what does it mean when the forces are balanced?)?
Air moves from high to low pressure (pressure gradient force) ---> other forces take action ---> feedback processes ---> balanced forces
Air moves from high to low pressure (pressure gradient force) ---> friction and Coriolis force take action ---> feedback processes (friction reduces wind speed which weakens the Coriolis force, no longer kept perpendicular to the PGF)---> balanced forces (slowed wind crossing isobars at an angle)
In cyclones air is crossing isobars going around a _____ pressure point and causing ____________. In anticyclones air is crossing isobars around a _________ pressure point and ____________ _________.
low, clouds, high, dispersing clouds
Which is faster, horizontal or vertical movements in the atmosphere?
horizontal
Pressure ___________ slower with height in ___________ air than with cold air
decreases, warm
In barotropic weather ______________ and ______________ are parallel, wind speed ____________ with height and its _____________ is constant.
isotherms and isobars, increases, direction
In baroclinic weather isotherms and isobars (are/are not) parallel, wind speed ____________ with height and its direction (is/is not) constant.
are not, is not
Baroclinic weather produces thermal ______________.
advection
Baroclinic weather is most common in the ___________ _________________.
lower troposphere