Geographical distributions of Halogen Occultation Experiment (HALOE) aerosol extinction data for 1993--1998 are analyzed in the troposphere and stratosphere at pressures between 121 and 46 hPa. The El Ni¿o conditions of 1997 increased upper tropospheric cirrus over the mid-Pacific and decreased cirrus over Indonesia. Longitudinal centroids of cirrus in the Pacific and over Indonesia shifted eastward by 25¿ in the troposphere in 1997. Longitudinal centroids of aerosol in the lower stratosphere do not exhibit longitudinal shifts in 1997, indicating that the effects of El Ni¿o upon equatorial particle distributions are confined to the troposphere. The correlation of the longitudinal centroids of outgoing longwave radiation and HALOE extinction confirms the spatial relationship between deep convective clouds and upper tropospheric cirrus. The number of cirrus events observed each year in 1993--1998 in the upper troposphere are quite similar for the region from the Indian Ocean to the mid-Pacific (30 ¿S to 30 ¿N, 50¿ to 240 ¿E). ¿ 2000 American Geophysical Union