EVALUATION OF SEA-SALT ORIGIN POLLUTANTS IN PRECIPITATION AT AKITA USING CONSTRAINED OBLIQUE ROTATIONAL FACTOR-ANALYSIS

The validity of the classification of sea-salt and non-sea-salt origin s of pollutants in precipitation was evaluated using a constrained obl ique rotational factor analysis. The precipitations used for this anal ysis were collected from April, 1993 to March, 1995 in Akita and from January to March of 1994 and 1995 in Yuzawa on a day-after-day basis. The chemical compositions in these precipitations were analyzed and th eir four sub-data-sets (a two-year data-set of Akita, a data-set of wi nter season in Akita, a data-set of seasons except for winter in Akita and a data-set of winter season in Yuzawa) were analyzed using the fa ctor analysis. Three or four pollutant sources were quantitatively ext racted for each data-set. The factor analysis has extracted a factor a scribed to the sea-salt (ss) component without using any information c oncerning its composition. However, a part of the sodium and chloride ion is also involved in another acidic factor, which contains sulfuric acid. This means that part of sea-salt particles suffered a chemical reaction while coming to the precipitation place from the Sea of Japan .