I came up with other factors that are more significant.
1) CO2 causes hotter hemisphere in summer and cause extra evaporation. This probably create more cloud for extreme weather and block sun for other hemisphere for extreme cold winter. This explains antarctic ice increase.
2) This means more difference in temperature of earth crust and thus move potential movement due to temperature dependent size changes.
3) At certain point, cloud causes more cooling and combine with volcanic sulfuric acid and sun cycle, earth have “straw that broke camel’s back” effect and start to cool.
4) When crust start to cool it shrink and pressures magma inside and increase the chances of eruption.
I just come up with mechanics of sea level increase and increase in earthquake and volcanic activity. Japanese data shows decoupling and acceleration for tectonic movement. Basically reduction in static friction.
What is happening is two overlapping plate with high pressure moving toward each other. Basically Japan on top and pacific ocean floor as bottom plate. As sea rises, pacific plate get push down and less pressure upward pressure from pacific plate thus less static friction and faster movement.
Picture this by placing two open hand in front of you face down and left hand fingers on top of right hand nails and apply pressure which will resist hands moving toward each other inward, imagine some force that places right hand down, it will make inward movement easier.
Below is short video of tectonic plate slide explained.
As for volcanic activity in Hawaii. It is like a water bed(plastic case being pacific plate) with hole. When more pressure from higher water level squeeze lava from a hole(water from water bed).