Quiz #4 Study Guide
 
Newton's 1st law of motion (15 pts).  Given a picture of an object's motion, you should be able to determine whether a net force is acting on the object or not. If a net force is present, you should have some idea what direction it must point.  Here are some examples. 

Forces that determine horizontal wind (25 pts).   Pressure gradient force (PGF), Coriolis force (CF), and frictional force (F) (surface winds only). Rules that determine the direction and strength of these forces. Which force can start stationary air moving? Which of these forces will only change the direction of the wind and not the wind speed? Which one of these forces can only change the speed of the wind?  Which of these forces is always perpendicular to the contours on a weather map, which is always perpendicular to the wind? 

Upper level and surface winds (40 pts).  Upper level winds blow parallel to the contours, surface winds blow across the isobars toward low pressure.  You should know the directions that upper level winds blow around circular high and low pressure centers in the northern and southern hemisphere.   In each case you should be able to determine the directions of the PGF and CF.  Here are lots of examples to study. 

How do surface winds blow around H and L pressure centers in the northern and southern hemispheres? Where do you find rising and sinking air motions?  Here are several examples.
Sample Questions from the Fall 2000 quiz packet      Quiz #5: 4, 5?, 7, 12, 13, EC2        Final Exam: 10, 13, 18, 26, 27

Thunderstorms (25 pts). Ordinary single cell (air mass) and severe thunderstorms. How might you distinguish between an air mass and a severe thunderstorm?  Life cycle of an air mass thunderstorm (3 easy to remember stages). How can the dissipation of one storm lead to the formation of another? Thunderstorm features and, in some cases, processes that produce them: gust front, anvil cloud, shelf cloud, mammatus clouds, microburst. Wind shear. Why can a storm with a tilted updraft become stronger and last longer than a storm with a vertical updraft? Supercell thunderstorms.  Mesocyclone, wall clouds, and hook echoes (on radar).

Tornadoes (25 pts). Average characteristics: low pressure core, duration, length of path on the ground, diameter, speed of rotating winds, speed and usual direction of the movement on the ground. Tornado season (when do the most tornadoes occur, when do the strongest tornadoes occur).  Life cycle.  What causes the tornado cloud?  Fujita (and the newer EF) scale. Tornado winds and damage. Multiple vortices, suction vortices.  Tornado watches and warnings. 

Lightning (20 pts). What creates the electricity in thunderstorms? Normal distribution of electrical charge in a thunderstorm. Types of lightning discharges, intracloud, negative and positive cloud-to-ground lightning, and upward lightning. Sequence of events in a multi-stroke cloud-to-ground lightning flash: stepped leader, upward connecting discharge, first return stroke, dart leader(s) and subsequent return stroke(s). Unusual types of lightning and rocket-triggered lightning. Lightning hazards and safety. What produces thunder? Determining the distance to a lightning strike.  How/why do lightning rods and cars offer protection from lightning?

Sample Questions from the Fall 2000 packet.
Quiz #6: 1-5, 7-11, 13-16      Final Exam: 4, 28, 33, 39, 51

Hurricanes (25 pts).  Formation (where and when). Eye, eye wall, spiral rain bands, low pressure & converging winds at surface, high pressure & diverging winds aloft. Stages of storm development. Storm surge and hurricane damage, Saffir-Simpson scale.

Sample Questions see this list of questions.

Reviews

Tues., Dec. 2
 4 - 5 pm
 Haury (Anthropology) 129
Wed., Dec. 3
 4 - 5 pm
Haury (Anthropology) 216