SAGE II Observations

The SAGE II satellite instrument, launched in 1984, observed the dispersal of volcanic aerosols following the massive eruption of Mt. Pinatubo in 1991. These measurements were crucial in linking a decline in the globally averaged surface temeprature in mid-1992 of about 1 degree Fahrenheit to the large aerosol concentrations from the volcanic eruption. Aerosols from Mt. Pinatubo also strongly influenced the observed ozone trend--an effect that would not have been detected without measurements like those from SAGE II. The data provided unique insight into the complex flow of air in the stratosphere that is needed to gain a better understanding of how the upper atmosphere will respond to climate change.