An analysis is made of the phenomenon of self-induced erosion and spectral
breaking of ionizing high-power microwave pulses propagating in a gas. The
analysis describes in an analytically explicit and physically clear way the
consistent interaction between the microwave pulse and the self-induced br
eakdown plasma. In particular, it clarifies; both qualitatively and quantit
atively, the mechanisms behind the pulse erosion and the spectral breaking
phenomenon, i.e. the splitting of the pulse spectrum into a redshifted and
a blueshifted peak as: observed in numerical simulation results as well as
in experiments.