Lidar observation of stratospheric aerosol increase after the El Chichon eruption: Nagoya, April to December 1982

摘要

The volcano El Chichon (Mexico) erupted violently over several days at the end of March and at the beginning of April 1982. After the eruptions a sudden increase of backscattered light from the stratospheric aerosol layer was detected by a lidar (0.6943μm) at Nagoya (35°N, 137°E) in mid-April 1982. At the end of May the observed scattering ratio reached the maximum value about 44. The effect of the eruption of El Chichon on the stratospheric aerosol layer seems to be larger than that of the volcan de Fuego eruption or Mt. St. Helens eruption. Immediately after the eruption, an apparent two-layer structure of scattering ratio profiles was observed. According to the radio sonde data over Japan, the aerosols in the upper layer were possibly transported by easterly wind and those in the lower layer by westerly wind, respectively. After September 1982 the centroid height of particulate backscattering and the main peak height decreased gradually due to the effect of sedimentation.