Abstract
The decay of stratospheric aerosol content after the volcanic eruption of Mt. Fuego (Oct. 1974) is discussed on the basis of laser radar measurements at Nagoya (35°N, 137°E). The results show that the decay time constant of stratospheric aerosol content is about 2 years, and this value is a little longer than the previous measurements (Hofmann and Rosen, 1977; Russell and Hake, 1977). This discrepancy is due to mainly the difference of observational periods between present and previous analysis, and observational periods were too short to make clear the decay time scale in previous investigations. More recently, Reiter et al. have summarized the results measured at many different laser radar sites (1980). It can be easily found out in their results, though they didn't present the value of decay time scale, that the decay time scale was about 2 years. This value is comparable one with present result.
