Answer
These large jumps occur because removing core electrons from an element requires much more energy to remove than valence electrons. Valence electrons are held more loosely and can therefore be transferred or shared most easily. Core electrons, on the other hand, are held tightly and are not easily transferred or shared.
Work Step by Step
We can predict when these jumps will occur for elements by examining their electron configurations and determining the number of valence electrons that they have. Once all of the valence electrons are removed, a stable noble gas configuration results, and a large jump for the next ionization energy will occur when a core electron is removed from this ion.