MEASUREMENT OF AEROSOL OPTICAL DEPTH IN THE PACIFIC-OCEAN AND THE NORTH-ATLANTIC

The results of spectral aerosol optical depth measurements in the Paci fic Ocean and in the North Atlantic are presented. Comparisons of aero sol optical depth spectra indicate that the optical properties of the maritime aerosols influencing Pacific Ocean measurements ate substanti ally different than those of the North Atlantic data. The values of th e Angstrom parameter calculated in the 461-to 1016-nm range for the Pa cific Ocean data are about a factor of 2 less than those for the North Atlantic. For the Pacific Ocean data an increase in optical depth wit h increasing wavelength in the 1016-to 1640-nm range is attributed to a narrow mode coarse size distribution. This mode is found to be subst antially independent of the fine mode variability. In contrast the fin e and coarse modes are well correlated for the North Atlantic data.