What is the approximate dry adiabatic lapse rate per 100 meters?

What is the approximate dry adiabatic lapse rate per 100 meters?

• A. -1 C
• B. -0.5 C
• C. -2 C
• D. +1 C

Answer: (A)

Dry adiabatic lapse rate describes how the temperature of a rising air parcel changes without heat exchange with its surroundings. It’s about 9.8 C cooler for every 1,000 meters of ascent, which works out to roughly 0.98 C cooler per 100 meters. Since the parcel cools as it climbs, the rate is negative, about -1 C per 100 meters. So the approximate dry adiabatic lapse rate per 100 meters is -1 C. The other options don’t fit: -0.5 C would be a gentler cooling (about 5 C per 1,000 m), -2 C is steeper cooling (about 20 C per 1,000 m), and +1 C would imply warming with height, which isn’t correct for a rising dry parcel.

Dry adiabatic lapse rate describes how the temperature of a rising air parcel changes without heat exchange with its surroundings. It’s about 9.8 C cooler for every 1,000 meters of ascent, which works out to roughly 0.98 C cooler per 100 meters. Since the parcel cools as it climbs, the rate is negative, about -1 C per 100 meters. So the approximate dry adiabatic lapse rate per 100 meters is -1 C.

The other options don’t fit: -0.5 C would be a gentler cooling (about 5 C per 1,000 m), -2 C is steeper cooling (about 20 C per 1,000 m), and +1 C would imply warming with height, which isn’t correct for a rising dry parcel.