Stratospheric aerosols from the El Chichón eruption weakened in August over Japan, Hawaii, and Virginia.

The following is a report from William Fuller. "An airborne lidar mission supporting the SAGE II/SAM II correlative measurement experiment was flown on the NASA Wallops P-3 aircraft on 7, 8, and 9 August 1985 from Fairbanks, Alaska. SAGE II missions were flown on 7 and 9 August just south and north of Fairbanks (64.8°N, 147.9°W) and SAM II measurements were conducted to 74°N. Other correlative measurements supporting the experiments were as follows: in-situ balloon-borne aerosol, water vapor, ozone measurements, and higher-altitude sampling from a NASA U-2 aircraft. Sun photometer data were also obtained on the P-3 flights. One set of data was taken at the Wallops flight facility on 2 August prior to departing for Alaska. Peak scattering ratios from 63°N to 74°N were approximately the same as at 38°N latitude, on the order of 1.4. The peaks occurred at lower altitudes because of the lower tropopause heights at high latitudes (10 km at 64°N, 16 km at 38°N."

Information Contacts: W. Fuller, NASA; M. Hirono, Kyushu Univ. Japan; T. DeFoor, MLO.