[schiffern]

As I understand it, the concern is not just AlO but specifically nanoparticles with high reaction surface area and long lofting lifespans.

The importance of this distinction is acknowledged in Brady et al (1994):

  >The exact chemical nature, as well as size distribution (and total surface area) of particles formed in rocket exhaust in the stratosphere is currently unknown. Preliminary experiments at Aerospace by L. R. Martin indicate that plausible particle compositions give highly variable rates of direct ozone destruction.

The 17 t/year and 360 t/year figures are specifically for AlO nanoparticles (formed by hypersonic ablation), whereas Brady et al gives numbers for all AlO particles, regardless of size.

Nice username btw.