The nonlinear spatial evolution of the auroral electron beam and beam-generated electrostatic whistler noise is followed from source to atmosphere. Changes in beam parameters are determined by using the equations of conservation of total particle and wave energy and momentum flux density. Wave power fluxes are calculated by numerically integrating the wave kinetic equation. Levels of beam generated noise are quantified by using thermal levels of Cerenkov radiation as a source. Wave refraction and source geometry as well as beam recoil and thermalization influence beam generated power flux spectra. Beam parameters evolve on ionospheric scale lengths, and their positive slope feature in velocity space is maintained over thousands of kilometers of altitude even though they can generate wave energy density fluxes sufficient to modify the ionospheric density profile. For a beam source at 7000 km altitude, peak fluxes of electrostatic whistler noise as high as 10-10 W/m2 Hz can be generated in the altitude region between 3000 and 5000 km. Beams with densities large enough to be unstable at the source altitude generate sufficient wave noise at the plasma frequency to disrupt the source structure. ¿ American Geophysical Union 1989