Meteorology Skew-T Log-T Problem:
A parcel of air with temperature 15C, dew point 6C and pressure 950 hPa is moving over a mountain.
Use the SkewT/log-P chart as fit
a) Using the chart, find the potential temperature (To) and mixing ratio (w) of the parcel at an air pressure (P) of 950 hPa on the windward side of the mountain. Calculate the relative humidity (RH). b) Using the chart, determine and label the lifting condensation level (LCL). What are P, dew point temperature (Ta), To, w and RH of the parcel at the LCL? c) Precipitation occurs as the parcel rises to the top of the mountain where P is approximately 690 hPa. If the new w is 4 g/kg, what are the air temperature (Ta), Td, To, and RH? d) The air parcel then descends on the leeward side of the mountain back to a P of 950 hPa. What are Ta, Ta, Te, w and RH of the parcel when it reaches 950 hPa? LCL Surface Level Windward Side Top of Mountain Surface Level Leeward Side Pressure 950 hPa 690 hPa 950 hPa Air Temperature 15C Dew Point 6C Potential Temperature Mixing Ratio 4 g/kg Relative Humidity e) Did Ta and RH of the parcel change as it moved over the mountain? Why, or why not? Temperature (C) a o o 6 o 37.5 St 40 - 35C 8 os oc 32.5 5 OX 30 2 6 27,5 386 os 25 CM 371 s 22.5 358 . By ocio- 346 20 Temperature (C) 2 336 327 15 12.5 318 70C 10 311 60 305 1 5 50 293 0 O 40 283 5 02 -10 275 20 -15 A 268 -20 261 10-6 -25 255 0 SA 249 -30C 2004 400 500 600 700- 800 -006 1000 Pressure (hPa) 151 14 131 127 + N 31 P Height of Standard Atmosphere (km) TZA a) Using the chart, find the potential temperature (To) and mixing ratio (w) of the parcel at an air pressure (P) of 950 hPa on the windward side of the mountain. Calculate the relative humidity (RH). b) Using the chart, determine and label the lifting condensation level (LCL). What are P, dew point temperature (Ta), To, w and RH of the parcel at the LCL? c) Precipitation occurs as the parcel rises to the top of the mountain where P is approximately 690 hPa. If the new w is 4 g/kg, what are the air temperature (Ta), Td, To, and RH? d) The air parcel then descends on the leeward side of the mountain back to a P of 950 hPa. What are Ta, Ta, Te, w and RH of the parcel when it reaches 950 hPa? LCL Surface Level Windward Side Top of Mountain Surface Level Leeward Side Pressure 950 hPa 690 hPa 950 hPa Air Temperature 15C Dew Point 6C Potential Temperature Mixing Ratio 4 g/kg Relative Humidity e) Did Ta and RH of the parcel change as it moved over the mountain? Why, or why not? Temperature (C) a o o 6 o 37.5 St 40 - 35C 8 os oc 32.5 5 OX 30 2 6 27,5 386 os 25 CM 371 s 22.5 358 . By ocio- 346 20 Temperature (C) 2 336 327 15 12.5 318 70C 10 311 60 305 1 5 50 293 0 O 40 283 5 02 -10 275 20 -15 A 268 -20 261 10-6 -25 255 0 SA 249 -30C 2004 400 500 600 700- 800 -006 1000 Pressure (hPa) 151 14 131 127 + N 31 P Height of Standard Atmosphere (km) TZA
