Playing along for a bit...
Have you considered reverse causation? Specifically that rather than the disasters being the response to human actions on those specific dates, its possible that those dates were chosen specifically because disasters were going to strike soon?
Imagine some super-secret organization with key players in politics, science, technology, economics etc. who have the means to predict within the range of hours exactly when natural disasters are going to occur. And whatever their secret agenda is, it dictates that they oush along these treaties, while indicating that some powerful force is not happy with it - a card to be played in future. So they arrange to have these things done a day before or on the day of the disaster. Now that's a conspiracy theory.
Have you considered reverse causation? Specifically that rather than the disasters being the response to human actions on those specific dates, its possible that those dates were chosen specifically because disasters were going to strike soon?
Imagine some super-secret organization with key players in politics, science, technology, economics etc. who have the means to predict within the range of hours exactly when natural disasters are going to occur. And whatever their secret agenda is, it dictates that they oush along these treaties, while indicating that some powerful force is not happy with it - a card to be played in future. So they arrange to have these things done a day before or on the day of the disaster. Now that's a conspiracy theory.