But not so high as the Tunguska event, which is estimated at 10 km for the center of the explosion. Although it's the effect on the water vapor in the troposphere and mesosphere that the author argues is different between the volcanoes and nuclear tests on the one hand, and the Tunguska event.
He also argues that the effect is at permanent, or at least of longer lasting effect than events lower in the atmosphere.
When a nuclear charge explodes at the Earth’s surface or in the atmosphere, the shock wave vents water vapor from the troposphere to the stratosphere through tropopause.
For some period (approx. 3 years) water vapor in the stratosphere and aerosol, and dust in the troposphere and stratosphere suffice for the defense of the Earth from solar radiation. But then all gradually settled, and global warming continued.
All nuclear explosions above the ground and the sea together gave rise to tendency for decreasing the global temperature of Earth’s surface. The last nuclear test in open atmosphere was on the 16th October 1980.
Interesting.
If the Tunguska event was an exploding meteorite (or even a comet), and the explosion pushed water vapor higher up or even added some of its own to the mix, then according to the paper, the conclusion could be drawn that atmospheric nuclear testing is all that has interrupted a linear trend in temperature increases since 1908.
Further the conclusion could be drawn that the cause of the warming is not human, or even necessarily solar activity (although that may be a factor), but the Tunguska event and the associated displacement of water vapor. Hmmmmm.