1. When _____ moist air passes over a surface which is _____ than the dew point of the air, _____ fog can form. This occurs over _____.
a. Cool. Warmer. Radiation. The sea.
b. Warm. Cooler. Radiation. The land only.
c. Cool. Warmer. Frontal. Land.
d. Warm. Cooler. Advection. land and sea.
2. Radiation fog is most likely at an inland airfield in the UK with a relative humidity of 80% in the _____ with _____ and a wind of _____.
Autumn. Clear skies. 2-8 knots.
Spring. 6/8 ST and SC. 2-10 knots.
Winter. Clear skies. 15/20 knots.
Summer. Clear skies. no wind.
3. Fog may be defined as:
A reduction of visibility to less than 1000 metres due to the presence of water vapour in the atmosphere.
A reduction of visibility to less than 1000 metres due to the presence of water droplets in suspension in the atmosphere.
A reduction of visibility to less than 1500 metres due to the presence of water droplets in suspension in the atmosphere.
A reduction of visibility to less than 1000 ft due to the presence of water vapour in the atmosphere.
4. Several types of pressure distribution may be associated with radiation fog but all have one feature in common which is:
Closely spaced isobars.
A tight pressure gradient.
A slack pressure gradient.
A rapidly falling pressure.
5. Advection fog:
Only occurs at night and early morning.
Is most likely with Polar Maritime air.
Will only clear by insolation.
Can sometimes last for 24 hours in winter.
