Both bands share the physics of low microwave: humidity and refractivity
gradient build ducts the same way, and rain + gas absorption are
effectively zero at VHF/UHF. humidity_effect is :beneficial, rain_k /
rain_alpha are (0, 1), and o2_db_km / h2o_coeff are 0.
Range estimates reflect tropo reality: 2m ducts can reach 2500+ km
under exceptional conditions (e.g. documented Hawaii ↔ California
openings), 70cm a bit less. The seasonal base matches the low-microwave
summer-peak curve.
These configs do NOT capture sporadic-E, meteor scatter, or aurora —
those need ionospheric data (GIRO ionosondes, NOAA SWPC) we don't yet
ingest. The scoring on these bands is therefore "tropo-only" and will
underestimate openings driven by ionospheric modes.
Graham McIntire
91c8cc9bc7