Fundamentals of Air Pollution Meteorology Prof.JIANG Dahe
Fundamentals of Air Pollution Meteorology Prof. JIANG Dahe
1.1 Composition of air and vertical stratification Minor components of clean air Atmospheric stratification Pressure(mb) 0 200 400600800 10001200 Gas % 100000 ppm Thermosphere H20 0~7 90000 C02 80000 0.032 CH4 70000 1.5 Mesosphere co 60000 0.1 Stratopause 50000 03 0.02 40000 NH3 0.01 Stratosphere 30000 NO2 0.001 20000 S02 0.0002 Tropopause 10000 H2S 0.0002 Troposphere 0 100 -80 60 -40 -20 0 20 Temperature(C)
Gas % ppm H2O 0~7 CO2 0.032 CH4 1.5 CO 0.1 O3 0.02 NH3 0.01 NO2 0.001 SO2 0.0002 H2S 0.0002 Minor components of clean air Atmospheric stratification 1.1 Composition of air and vertical stratification
The troposphere is further divided: According to the effect of the earth surface: -planetary boundary layer(PBL,1~2000m)and free atmosphere Within PBL,according to vertical wind profile: Geostrophic wind -Ekman layer Lower atmosphere(0~150m) Constant shear layer
The troposphere is further divided: • According to the effect of the earth surface: – planetary boundary layer (PBL,1~2000m) and – free atmosphere • Within PBL, according to vertical wind profile: – Geostrophic wind – Ekman layer – Lower atmosphere (0~150m) – Constant shear layer
1.2 Principle meteorological factors Temperature Fahrenheit(F),Celsius(C),Kelvin Celsius =(Fahrenheit-32)x5/9 Kelvin Celsius 273.16 Humidity Absolute humidity a(mass/volume) Relative humidity actual water vapor P/saturation vapor P at T Dew point temperature Specific humidity
1.2 Principle meteorological factors • Temperature Fahrenheit (F), Celsius(C), Kelvin Celsius = (Fahrenheit – 32) ×5/9 Kelvin = Celsius + 273.16 • Humidity Absolute humidity a (mass/volume) Relative humidity = actual water vapor P / saturation vapor P at T Dew point temperature Specific humidity …
-Absolute humidity is the water mass per unit volume, (mg/m3). Water vapor pressure(hPa),is a partial pressure, which equals to the pressure of the air parcel where the dry air were not there but the water vapor. Saturated water vapor pressure,(hPa),is the water vapor pressure at saturation of the same temperature. Relative humidity refers to the ratio of water vapor pressure to saturated water vapor pressure,(% Dew point temperature(K)is the temperature when the air parcel is cooled to condensation under constant pressure
– Absolute humidity is the water mass per unit volume, (mg/m3). – Water vapor pressure (hPa), is a partial pressure, which equals to the pressure of the air parcel where the dry air were not there but the water vapor. Saturated water vapor pressure, (hPa), is the water vapor pressure at saturation of the same temperature. – Relative humidity refers to the ratio of water vapor pressure to saturated water vapor pressure, (%) – Dew point temperature (K) is the temperature when the air parcel is cooled to condensation under constant pressure