Since that time, the explosive yield estimates varied widely, and in some cases, were inconsistent with what would be expected based on the amount of ammonium nitrate stored at the Beirut harbor. In addition, the crater size, seismic magnitude and mushroom cloud height seemed to be inconsistent.

Lawrence Livermore National Laboratory (LLNL) physicist Peter Goldstein has studied how water saturation of the explosive, ground and possibly water and debris from the near-source environment can help reconcile differences in the yield estimates obtained using these different measurements. Official records indicate that roughly 2.7 kilotons of explosive material were stored at the Beirut harbor warehouse where the explosion occurred. The detonation of these materials resulted in a large crater and seismic measurements suggested it was possible that the yield was at least a few kilotons and possibly much greater. However, there were other estimates that suggested the yield was quite a bit smaller, possibly as little as half a kiloton.

Goldstein's research, which appears in Countering WMD Journal, analyzes the crater dimensions, seismic magnitude estimates and the cloud height of the explosion and shows that all the data are consistent with a yield of around a kiloton when water/saturation is accounted for. "Water in the near-source environment can have a significant effect on many observations, including crater formation, cloud rise, seismic magnitudes and blast wave effects," he said.

Goldstein used crater-size observations from satellite imagery and empirical data for scaled crater radii from past chemical and nuclear explosions to estimate the yield.