[Amelia]

Volcanic activity on Earth also has an impact. The 1993 Mount Pinatubo eruption in the Philippines caused ozone levels to backslide for several years, according to the researchers.

I think sunspot activity also has an effect.

[maine-iac7]

I think sunspot activity also has an effect.

Yep -

there was almost no to low sun spot activity during the coldest part of the Little Ice age - (about the mid 1300's to 1770's) and we are now heading into a high sun spot activity period...scientists (not the ones goreBore talks too) say that we are experiencing (and have been for the past 70 years) more sunspot activity than in the past 8000 years.

better get goreBore suited up. He needs to get up there and do something about it.