Conservation of Moisture The Moisture Equation Equation of

Conservation of Moisture The Moisture Equation

• Equation of State • 1 st Law of Thermodynamics (Conservation of Energy) • Moisture Equation (Conservation of Moisture) • Continuity Equation (Conservation of Mass) • Equations of Motion (Conservation of Momentum) – Coming to an ATMS 251 lab near you on March 22

Hydrologic Cycle – What can happen to moisture?

Moisture Equation • Mathematical representation of what can happen to water in a column of the atmosphere Change of moisture storage in the column Evapotranspiration from ground Moisture Inflow from atmosphere Precipitation Moisture Outflow from column

Precipitable Water • The vertical integral of the specific humidity for a column of atmosphere • Represents the upper limit to the total precipitation that may fall • Units: m (mm)

Average Specific Humidity for the layer Pressure Interval Sum up the number of levels This will yield the precipitable water in units of kg/m 2. To get PW in units of meters, divide by the density of water (ρw=1000 kg/m 3)

http: //www. osdpd. noaa. gov/PSB/IMAGES/images/amsua_tpw_des. gif

Moisture Advection • Of course, moisture can be transported horizontally and vertically in the atmosphere – Moisture Advection

http: //ww 2010. atmos. uiuc. edu/guides/mtr/af/adv/gifs/madv 1. gif