Visibility

Question 1

What is a visibility?

Answer 1

Maximum distance for recognising black object on bright background

Question 2

What determines atmospheric visibility?

Answer 2

Atmospheric visibility is determined by the number of particles suspended in the air.
- MAY SCATTER OR OBSCURE LIGHT

Question 3

How many meters for Fog (FG)?

Answer 3

less than 1000 m

Question 4

How many meters for mist (BR)?

Answer 4

1000 - 5000 m

Question 5

How many meters for haze (HZ)?

Answer 5

less than 5000 m

Question 6

How many meters for smoke (FU)?

Answer 6

less than 1000 m

Question 7

How many meters for volcanic Ash (VA)?

Answer 7

No specific number

Question 8

What is difference between haze and volcanic ash?

Answer 8

Haze has particles of water while volcanic ash has solid particles

Question 9

How many meters for Widespread Dust (DU)?

Answer 9

less than 5000 m

Question 10

What is fog comprised of?

Answer 10

It is comprised of water droplets or ice crystals

Question 11

How many meters for Widespread Sand (SA)?

Answer 11

less than 5000 m

Question 12

What is radiation fog?

Answer 12

Fog that is confined to low ground\
- typical on non-tropical regions and far away from coasts
- Usually in Autumn

Question 13

What are the three ingredients to make a fog?

Answer 13

High humidity, light wind and clear sky

Question 14

How can fog clear away?

Question 15

When does the fog form?

Answer 15

Usually at the winters, just after sunrise

Question 16

What is advection fog?

Answer 16

It is when warm moist air from source regions colds down in colder region, which creates the fog
(it can be a stratus cloud)

Question 17

Wat is steam fog?

Answer 17

When the air is colder than the water which creates steam fog

Question 18

Where can steam fog typically be found?

Answer 18

By the lakes

Question 19

What is a frontal fog?

Answer 19

The front of Nimbostratus cloud where the could rains

Question 20

What is Hill/Upslope fog?

Answer 20

Mountain or hill fog, usually created by the föhne effect

Question 21

How is radiation Fog formed?

Answer 21

Forms over the land on calm, clear nights in the autumn and winter months

Question 22

How is Advection fog formed?

Answer 22

Created when warm moist air moves over a colder surface

Question 23

How is steam Fog formed?

Answer 23

Created when cold dry air passes over a warm moist surface

Question 24

Reduced visibility for Precipition?

Answer 24

It depends on rain, heavy rain and drizzle

Question 25

Reduced visibility for solid particles?

Answer 25

Like smoke, or pollution suspended on air from industrial areas

Question 26

Reduced visibility for volcanic ash

Answer 26

extreme reduction in visibility

Question 27

What is blowing snow and drifting?

Answer 27

any loose snow lifted from the ground surface and suspended by strong winds at less hight of 2m, and beyond that is drifting snow

Question 28

Reduced visibility - Dust and Sand

Answer 28

Sand particles exceed 15-20kt

Question 29

Reduced visibility - windshield icing

Answer 29

Restricted visibility to window

Question 30

Reduced visibility - glare

Answer 30

light from the sun blinding the visibility

Question 31

Shallow angles?

Answer 31

The slant range is grater than vertical range

Question 32

What is ground visibility?

Answer 32

The prevailing horizontal visibility near earth’s surface

Question 33

RVA?

Answer 33

The distance over which a pilot of an aircraft on the centreline of the runway can see the runway surface marking delineating the runway or identifying its centreline
- RVR is higher than meteorological distance

Question 34

Transmissometer

Question 35

What is vertical visibility?

Answer 35

The distance one can see upward into a surface based on obscuration, or the maximum height from which a pilot in flight can recognise the ground through a surface based obscuration