Isn't Sulfur ok if it is in upper atmosphere, but in lower atmosphere causes acid rain??? So we could seed the upper atmosphere by shooting rockets into it (as

Isn't Sulfur ok if it is in upper atmosphere, but in lower atmosphere causes acid rain??? So we could seed the upper atmosphere by shooting rockets into it (as in book Termination Shock), and thus bypass the layer where the sulfur was being added by pollution and causing acid rain.