The mathematic expression for the extinction of contrast =oeXp[-b× b: scattering coefficient or absorption coefficient x: distance I: light intensity or contrast b=b+b+b.+b g p bsa and bsn are extinction coeff. caused by light scattering due to gas and particles respectively sp>+b are broken into contributions due to dr particles and water associated with particles b and bn are extinction coeff. caused by light absorption due to gas and particles respectivelyThe mathematic expression for the extinction of contrast: I =Io exp[-bx] b: scattering coefficient or absorption coefficient, x: distance I: light intensity or contrast. b = bsg + bsp + bag + bap bsg and bsp are extinction coeff. caused by light scattering due to gas and particles respectively. bsp = bsdp + bsw are broken into contributions due to dry particles and water associated with particles. bag and bap are extinction coeff. caused by light absorption due to gas and particles respectively