Weather

Question 1

One atmosphere is how many PSI?

Answer 1

14.7 PSI

Question 2

Wind Isobars

Answer 2

Contour lines on a weather chart representing equal pressures.

Question 3

Pressure Gradient

Answer 3

Is indicated by the spacing between isobars. Strength of wind is dependent on the Pressure Gradient. The closer the “contour lines” on a weather map the steeper the pressure gradient.

Question 4

Wind Velocity

Answer 4

Varies based directly with the pressure gradient.

Question 5

Direction

Answer 5

The direction from which the wind flows.

Question 6

Fetch

Answer 6

The distance over which the wind contacts the water (in the direction the wind is blowing.

Question 7

Swells

Answer 7

After being formed in the area of fetch, SWELLS can travel thousands of miles before breaking in shallow waters.

Question 8

Breakers

Answer 8

Formed by the distant wind / fetch.

Width of the fetch area.

Wind duration.

Water depth.

Question 9

Wave Trough

Answer 9

Lowest part of the wave

Question 10

Wave Crest

Answer 10

Highest part of the wave

Question 11

Wave Dimensions

Answer 11

Height = Trough to Crest
Length = Trough to Trough distance
Period = Time in seconds between Crests

Question 12

Northern Hemisphere

Answer 12

Wind flows counter clockwise around a LOW and clockwise around a HIGH.

Question 13

Buy Ballots Law

Answer 13

In the Northern Hemisphere if you stand with your back to the wind, the low pressure area will be on your left side.

Question 14

Backing Wind Shift

Answer 14

COUNTER clockwise shift of wind.
Example: SE Wind shift to a NE Wind
Pressure system will pass to your south

Question 15

Veering Wind Shift

Answer 15

CLOCKWISE shift of wind.
Example: SW wind shift clockwise to West Wind
Pressure system will pass to north

Question 16

Sea Breeze

Answer 16

High pressure cool air blowing off the water into warm air heated by the land.

Question 17

Warm Front

Answer 17

Occurs when a warm air mass advances and overtakes colder air mass.
-Less dense and slow moving
-Several days of grey rainy weather generally follow

Question 18

Cold Front

Answer 18

Occurs when a cool air mass advances and overtakes a warm air mass.
-Cold air is denser and buries under warm air, lifting it up.
-Cold fronts are faster and more intense than warm fronts.

Note: Cold fronts are frequently associated with:
-A line of clouds
-Sharp changes in wind direction
-Squalls

Question 19

Occluded Front

Answer 19

Formed when a cold front overtakes a warm or quasi-stationary front, pushing the warmer air up over the two cooler air masses.

Question 20

Types of Clouds

Answer 20

Cirrus, Cumulus, Stratus, Altocumulus, Cirrocumulus, Altostratus.

Question 21

Northern Hemisphere Storms

Answer 21

Dangerous RIGHT HAND semi-circle

Navigable LEFT HAND semi-circle

Question 22

Advection Fog

Answer 22

-Warm moist air moves over cold water.
-Known as coastal fog.
-Can last for days because the temp of seawater is fairly constant.

Question 23

Radiation Fog

Answer 23

Produced at night over the land when radiation cooling reduces air temp to or below the dew point.

Also called ground fog.

Question 24

Steam Fog

Answer 24

Cooler air lies over warmer air

Also called sea smoke

Question 25

Frontal Fog

Answer 25

Rain falls from warm air, down through cold air. Additional water vapor causes air to reach dew point.

Also called rain fog

Question 26

Frost

Answer 26

USCG describes frost as a light feathery deposit of ice caused by the sublimation of water vapor directly into crystalized form, on objects whose temperatures are below freezing.