Chapter 18 Vocabulary

Question 1

Pressure tendency

Answer 1

a low moving toward or away by falling or rising pressure

Question 2

wind

Answer 2

horizontal movement of air due to pressure differences caused by solar heating

Question 3

Pressure Gradient Force (PGF)

Answer 3

has both magnitude and direction and is the driving force of wind. Measured on weather maps and shown as isobars

Question 4

steep gradient

Answer 4

high speed & closely packed isobars

Question 5

Coriolis effect

Answer 5

freely moving objects turn to the right of their apparent direction of motion in the northern hemisphere and to the left in the southern hemisphere; a product of the rotating earth

Question 6

jet stream wind effects

Answer 6

geostrophic winds paralleling isobars several kilometers above the earth. Jet stream is a fast moving river of air from 75-150 mph moving west to east. One is situated over the polar front and sometimes splits into two jet streams, a northern and a southern branch

Question 7

cyclones

Answer 7

low pressure centers; winds blow inward and counterclockwise around a low pile up and rise (convergence) and diverge at high altitude and perpetuate itself. If upper air divergence increases the low may intensify

Question 8

anticyclones

Answer 8

high pressure with surface divergence; balanced by high altitude convergence and produces adiabatic heating of the air and tendency to clear conditions

Question 9

List the five basic assumptions

Answer 9

1. hot air rises; 2. pressure flows from high to low; 3. warm air can hold more moisture than cold air; 4. pressure decreases in the atmosphere as altitude increases; 5. Coriolis effect

Question 10

sea breeze

Answer 10

develops as air over land heats and rises, pulling in cooler air from the water beginning about noon