Meteo 431 Atmospheric
Thermodynamics Spring 2002
Problem set # 5
assigned:
8 February 2002
due:
15 February 2002
1. Consider an air parcel with the following characteristics: T = 300 K;
p =950 hPa; z = 0 km.
a. What is the parcel’s potential temperature?
b. What is its dry static energy?
Suppose this air parcel rises adiabatically to 4 km (e.g., the top of the PBL in Arizona in summer).
c. Find the air parcel’s temperature at 4 km by using conservation of dry static energy.
d. Find the air parcel’s temperature at 4 km by using the dry adiabatic lapse rate.
2. Suppose an air parcel has a temperature of 310 K when the environment has a temperature of 290 K. The pressure is 960 hPa.
a. What are the densities of the parcel and its environment?
b. What is the upward acceleration (buoyancy) of the air parcel?
c. Assumes that the air parcel ascends adiabatically. Explain the behavior of the air parcel for a typical vertical temperature profile.
3. Consider two air parcels with the following characteristics:
parcel 1: T = 310 K; p = 900 hPa; e = 40 hPa; V = 105 m3
parcel 2: T = 290 K; p = 900 hPa; e = 10 hPa; V = 3x105 m3
a. What are the enthalpies of the two air parcels?
b. What are the number of molecules of dry air and of water vapor in the two air parcels?
c. If the two parcels mix isobarically, what are the final T and e?
4. B&A, Chapter 3, #34.