Met (winds)

Question 1

surface winds on land and sea

Answer 1

Land 50% 30°, sea 70% 10°

Question 2

Friction layer depends on

Answer 2

1. Stability of air
2. Time of day: Strongest at mid-afternoon, weakest at night
3. Wind speed: Thicker when higher
4. Type of surface

Question 3

condition for the formation of mountain/standing/lee winds

Answer 3

• Wind speed more than 20kts, turbulence downwind side of range
• Wind blows at right angles to the mountain range or within 30°
• Wind speed increases with altitude up to tropopause but does not change direction
• Stable atmosphere, less stable above and below/inversion just above the crest
• Creates altocumulus lenticularis (Lens), rotor & cap clouds. Does not form when air is too dry

Question 4

Jet streams properties

Answer 4

Properties:
Length: 1000NM
Width: 150NM
Thickness: 18000ft
Height to width ratio = 1:100 
Wind speed: >60kts

Question 5

Summer Jets (July)

Answer 5

Polar Jet - 350FL
Subtropical Jet - 400FL
Equatorial Jet- 450FL

Question 6

Winter Jets

Answer 6

Arctic Jet- 200FL
Polar Front Jet- 300FL
Subtropical Jet- 380FL