Vayudoot Aviation

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

convergence and subsidence

divergence and subsidence

divergence and widespread ascent

convergence and widespread ascent

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

Cold air undercuts a warm air mass

Warm air overrides a cold air mass

Cold air overrides a warm air mass

Warm air undercuts a cold air mass

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

reduced to sea level

at flight level

at height of observatory

at a determined density altitude

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

rising pressure and likely formation of clouds

falling pressure and likely formation of clouds

falling pressure and likely dissipation of clouds

rising pressure and likely dissipation of clouds

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

Convergence with lifting.

Divergence with descending air.

Divergence with lifting.

Convergence with descending air.

6. Subsidence is

horizontal motion of air

the same as convection

vertically upwards motion of air

vertically downwards motion of air

7. 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

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

Convection.

Convergence.

Subsidence.

Advection.

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

thick low level cloud.

Calm winds, haze.

cumulus clouds and thunderstorms

showers and thunderstorms.

10. 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

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

Instability

Rising air

Sinking air

Divergence at higher levels

12. In an area of converging air

convective clouds can be dissolved

clouds can not be formed

stratified clouds can be dissolved

clouds can be formed

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

loses water vapour

reaches warmer layers

is heated by expansion

is heated by compression

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

strong

light

blowing perpendicular to the isobars

changing direction rapidly

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

An inversion over a large area with poor visibility.

Wide spread NS and AS clouds and intense precipitation

Clear air turbulence at higher altitudes.

CB-clouds and thunderstorms over a large area.

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

thick stratus with continuous rain.

The possibility of snow showers.

Thunderstorms.

A tendency for fog and low stratus

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

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

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

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

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

Question Bank

Questions for PRESSUE SYSTEM1