Seasonal and Solar Cycle Atmospheric Meteoric Metal Content Changes

High temporal resolution vertical column contents of the most dominant meteoric metal species, Mg+, Mg, Fe+, Fe, and Si have been measured pole-to pole at ~ 10:30 AM using the nadir-viewing Global Ozone Measuring Experiment (GOME) UV/VIS spectrometer on the ERS-2 satellite. Emphasis initially was placed on the month of November and latitudes between 10 and 30 degrees, which encompass the Leonid meteor shower period and radiant location. Metals were more abundant in 2000 than in 1996 showing a solar cycle dependence. This reflects atmospheric control of the ablation and the metal ion and neutral chemical processes. This atmospheric control, rather than changes in the meteoroid influxes is also demonstrated by the changes in the metal abundances for equinox winter and summer months. To compare the solar activity influence to that of the seasonal atmospheric changes, the variations of the metal species vertical contents were extracted from the GOME measurements for monthly periods centered on the June and December solstices and on the March and September equinoxes for both 1996 and 2000, as in the first study.