Um, didn't we intentionally denotate at least that much in the 1950s?
Between China, The USSR, and the US, I would think that we easily blew up 100 MT of stuff in a 20 year period.
The author mentions these tests. In fact he credits them with temporarily stopping the planetary temperature rise. The figures showing this are in his paper They were not at as high an altitude, most were surface or subsurface detonations and most were not nearly so large individually. (the largest was bigger however, the Soviets did a one time demonstration of 50 MT, which was detonated at 4 km altitude)