it is very important to determine the stable nitrogen isotope ratio for the nitrogenous substances in aerosols and the geochemistry behavior of stable nitrate ion isotopes in aerosols in order to elucidate the chemical and physical functions of clouds. hence, aerosol field sampling was conducted in the skies offshore from malibu beach and santa barbara, california, u.s.a. on 16 and 18 july 2009...