Here is my personal analysis of the Fukushima Daiichi 1 explosion that occurred March 12, 2011. It is possible that the cooling water level in the spent fuel storage pool dropped enough to expose the fuel elements. This could generate hydrogen gas, and is a potential source of the explosion. Hat tip to the Nuclear Energy Institute for providing an image of the reactor design and secondary containment area.
I have created a Prezi to walk you through my thoughts.
I welcome your thoughts in the comments area.
Thanks for watching, and keep praying for the Japanese people as they continue to battle the after effects of this earthquake.