Thermodynamics and Atmospheric Stability Flashcards
6 cards from real AMS practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Thermodynamics and Atmospheric Stability flashcards as text
What does the CIN (Convective Inhibition) represent on a sounding?
Answer: Energy that must be overcome by lifting to reach the LFC
CIN represents the negative buoyancy energy that must be overcome before a parcel can reach the LFC and convect freely.
The moist adiabatic lapse rate (MALR) is approximately what value near the surface?
Answer: 4–7°C/km
The MALR varies from about 4°C/km in warm moist air to 7°C/km in cooler air, less than the DALR due to latent heat release.
What is potential temperature (theta) and why is it useful?
Answer: Temperature a parcel would have if brought adiabatically to 1000 hPa; conserved in dry adiabatic motion
Potential temperature is conserved during dry adiabatic processes, making it ideal for identifying airmass properties and stability.
What type of lapse rate produces absolutely unstable conditions?
Answer: Lapse rate greater than the DALR
Absolute instability occurs when the environmental lapse rate exceeds the dry adiabatic lapse rate (~9.8°C/km), causing any parcel to accelerate upward.
On a Skew-T log-P diagram, the dew point profile indicates what?
Answer: Moisture content as a function of pressure
The dew point profile on a Skew-T shows the moisture content of the atmosphere as a function of pressure level.
What stability index combines wind shear and instability to assess severe weather potential?
Answer: Storm Relative Helicity (SRH)
Storm Relative Helicity (SRH) measures the potential for rotating updrafts by combining low-level wind shear with the storm motion vector.