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