CBM Atmospheric Thermodynamics 5

Question 1

Which conditions most favor a strong surface-based radiation inversion overnight?

Accepted Answer

Clear skies, light winds, and dry air

Answer

Clear, calm, dry nights let the ground lose longwave radiation efficiently and cool the air just above it.

Question 2

A subsidence inversion is most commonly associated with which feature?

Accepted Answer

Sinking air within a high-pressure system

Answer

Air sinking under high pressure warms by compression and dries, creating a warm, dry inversion aloft.

Question 3

What is the convective temperature on a sounding?

Accepted Answer

The surface temperature needed for a parcel to rise freely and form cumulus without forced lifting

Answer

Once the surface reaches the convective temperature, surface heating alone can start free convection and cumulus formation.

Question 4

A 'loaded gun' sounding typically features what?

Accepted Answer

Moist low levels capped by a warm, dry elevated mixed layer with steep lapse rates above

Answer

A cap holds back rich low-level moisture under steep mid-level lapse rates, so large instability builds until the cap breaks.

Question 5

Why do forecasters watch the wet-bulb zero height for hail?

Accepted Answer

A lower wet-bulb zero means less melting, so hail is more likely to reach the ground

Answer

A low wet-bulb zero, often about 7,000-10,000 ft, reduces melting of falling hailstones.

CBM - Certified Broadcast Meteorologist Practice Test