Vayudoot Aviation

1. A blocking anticyclone on the northern hemisphere is

quasi stationary/situated between 50°N and 70°N,/a cold anticyclone

situated between 50° and 70°N/a cold anticyclone/steering depressions

a cold anticyclone/steering depressions/situated over Scandinavia

a warm anticyclone/quasi stationary/situated between 50°N and 70°N

2. Divergence in the upper air results, near the surface, in

rising pressure and likely dissipation of clouds

falling pressure and likely formation of clouds

rising pressure and likely formation of clouds

falling pressure and likely dissipation of clouds

3. How do air masses move at a warm front?

Cold air undercuts a warm air mass

Warm air overrides a cold air mass

Warm air undercuts a cold air mass

Cold air overrides a warm air mass

4. Where are you likely to find the strongest winds close to the ground?

In the transition zone between two air masses

At the centre of a high-pressure system

Where there is little variation in pressure over a large area during the winter months

At the centre of a low-pressure system

5. In temperate latitudes what weather conditions may be expected over land during the summer in the centre of a stationary high pressure zone?

showers and thunderstorms.

cumulus clouds and thunderstorms

thick low level cloud.

Calm winds, haze.

6. What is the correct term for the descending air flow in a large high pressure area?

Convergence.

Subsidence.

Convection.

Advection.

7. Extensive cloud and precipitation is often associated with a non frontal thermal depression because of

surface divergence and upper level convergence causing widespread ascent of air in the depression

surface convergence and upper level divergence causing widespread descent of air in the depression

surface convergence and upper level divergence causing widespread ascent of air in the depression

surface divergence and upper level convergence causing widespread descent of air in the depression

8. A trough of low pressure on a surface synoptic chart is an area of

divergence and widespread ascent

divergence and subsidence

convergence and subsidence

convergence and widespread ascent

9. What surface weather is associated with a stationary high pressure region over land in the winter?

The possibility of snow showers.

thick stratus with continuous rain.

A tendency for fog and low stratus

Thunderstorms.

10. Subsidence is

horizontal motion of air

vertically upwards motion of air

vertically downwards motion of air

the same as convection

11. What is the most likely cause of a lack of clouds at higher levels in a stationary high?

Divergence at higher levels

Rising air

Sinking air

Instability

12. Which of the following is a common result of subsidence?

CB-clouds and thunderstorms over a large area.

Clear air turbulence at higher altitudes.

Wide spread NS and AS clouds and intense precipitation

An inversion over a large area with poor visibility.

13. In an area of converging air

stratified clouds can be dissolved

convective clouds can be dissolved

clouds can be formed

clouds can not be formed

14. What type of air movement is associated with the centre line of a trough?

Convergence with descending air.

Divergence with descending air.

Divergence with lifting.

Convergence with lifting.

15. Areas of sinking air are generally cloudless because as air sinks it

reaches warmer layers

is heated by compression

loses water vapour

is heated by expansion

16. The isobars drawn on a surface weather chart represent lines of equal pressure

at height of observatory

reduced to sea level

at a determined density altitude

at flight level

17. When isobars, for an area in the mid-latitudes on a weather map, are close together, the wind is most likely to be

strong

blowing perpendicular to the isobars

light

changing direction rapidly

Question Bank

Questions for PRESSUE SYSTEM1