Rising Air Cools-Sinking Air Warms
8 m/s
494 m/s
502 m/s
502 m/s
494 m/s
Rising Expanding
Sinking Contracting
¥Rising air parcel expands
¥Expansion requires work against outside air
¥Air molecules rebound from ÒwallsÓ at a slower speed, resulting in a cooler temperature
¥Assuming no transfer of heat across parcel walls (adiabatic expansion), cooling rate is 10oC/km
10oC
20oC
no heat transfer
Ahrens, Fig 5.2
502 m/s