Question

Air at sea level with a temperature of 24° C is forced up a mountain slope and the dew point temperature is 8° C. At what elevation will condensation begin (LCL)?

Answer 1

1968.85 meters

Step-by-step explanation:

The Lifting condensation level (LCL) is defined as the height at which a parcel of air is completely saturated i.e the relative humidity of the air parcel reaches a 100%. All this must occur through dry adiabatic lifting.

At sea level, the pressure is given as 101.3kPa

air parcel temperature = 24°C

dew point temperature = 8°C

Using the LCL calculator, the pressure at which saturation occurs to the air parcel is 79.92KPa.

NB: LCL occurs through dry adiabatic lifting whereby the pressure on the air parcel reduces with height.

Using the hypsometric formula We can now convert the pressure into height

h = ((p1/p)^1/5257)-1 X (T + 273.15))/0.0065

where h= height, p1= Sea level pressure, p= atmospheric pressure, T = air temperature

h = ((101.3/79.92)^1/5257)-1 X (4+273.15))/0.0065 = 1968.85 meters