We divided the region into 26 sub-regions as shown in Fig.7, and analyzed occurrence frequencies of high salinity water. Salinity values from 34.70 through 35.0 at interval of 0.05 were selected as reference salinity values. The occurrence frequency of observation where salinity higher than each of these selected values was computed
for each sub-region. The frequencies in % are plotted against the selected salinity values in Fig. 8. The distribution pattern may be classified into 3 groups as shown in the figure. The region of the occurrence of these 3 grups are illustrated in Fig. 7. The important characteristics of the distribution patterns are that the all of the curves in Fig. 8 have tendency to reach to almost zero value near the salinity value a little larger than 34.90. Presumably, The ordinary salinity value in this region would be smaller than, say, 34.92.
However, small but significant occurrence frequency can be seen up to the salinity value a little larger than 35.00. Jusding form this distribution nature, we may set two kinds of salinity parameter, 34.92 and 35.02 for this region. If the observed salinity exceeds 35.02, the data would be erroneous, while, if the value exceeds 34.92, it night be real, but it is worth to be checked with original records or original field note.
