meteorology- winds and waves

Question 1

What are wind waves and swell waves

Answer 1

Wind waves (sea waves) are generated by the wind blowing at the position considered.
Swell waves are former wind waves that have travelled out of the area of generation or continue in an
area after the wind causing them has ceased.

Question 2

Waves form in the water surface that reacts with, what?

Answer 2

The airflow

Question 3

The characteristics of waves depend on what?

Answer 3

The wind speed

Question 4

Period, seconds, is the time taken between, what?

Answer 4

passage of one crest past a point and the passage of the next crest.

Question 5

Speed, knots, is what?

Answer 5

the speed of movement of the wave crest through the water.

Question 6

Speed kts = . x Period s.

Answer 6

3.1

Question 7

Length, meters is what?

Answer 7

the distance from the crest of one wave to the crest of the next wave.

Question 8

Height, meters is what

Answer 8

is the vertical distance between crest and trough of a wave.

Question 9

As wave height increases the shape changes to what?

Answer 9

Trochoidal, with sharper crests and broader troughs

Question 10

______, _______, _______, and ________ increase as waves grow with increasing wind speed, duration, and
fetch.

Answer 10

height
length
speed
period

Question 11

Steepness of a wave is the ratio of what

Answer 11

height to length

Question 12

What is steepness limited by

Answer 12

physical characteristics of water

Question 13

Waves break at a steepness of approximately what

Answer 13

1:13

Question 14

The ratios of waves exceeding the average height are:

Answer 14

2x 1:23
3x 1:1175
4x 1:300000

Question 15

Significant wave height is the average of what?

Answer 15

The highest third of waves

Question 16

Calm 0
Rippled 0-0._
Smooth 0.1-0._
Slight 0.-1.25
Moderate 1.25-._
Rough 2.5-_
Very rough 4-6
High 6-_
Very high 9-__
Phenomenal >__

Answer 16

1
5
5
2.5
4
9
14
14

Question 17

Wind wave height varies directly as

Answer 17

• wind speed, governing the energy available for wave generation.
• duration, the length of time over which the sea is influenced by the wind.
• fetch, the distance over which the wind affects the sea.

Question 18

What does the beaufort scale give

Answer 18

probable and probable maximum wave heights associated with wind force

Question 19

Swell waves are decreasing in ________ as the viscosity of the water absorbs _______.

Answer 19

magnitude
energy

Question 20

High waves contain most ______ and have long periods.

Answer 20

energy

Question 21

Swell wave height decreases and period _________.

Answer 21

increases

Question 22

Descriptive terms for swell waves.
Length
____ <100m
Average 100—___m
Long >200m

Height
Low <_m
_________ 2-4m
Heavy >4m

Answer 22

short
200
2
moderate

Question 23

Wind waves and swell waves are named by what?

Answer 23

The direction from which they come