A scanning flow cell with time-resolved downstream detection system is employed to analyse the corrosion behaviour of zinc in weakly alkaline hydrogen carbonate-containing electrolytes. Since zinc is usually exposed to varying environmental conditions, dynamic electrolyte exchange is used to investigate the impact of changing electrolyte constituents over time for the first time. The polarization resistance was monitored with galvanostatic pulses. Anodic current steps are applied to correlate the overall net current to the rate of precipitate formation. The results are complemented by investigations of the morphological features of the corroded surfaces and precipitates utilizing broad ion beam cross-sectioning techniques. (C) 2015 Elsevier Ltd. All rights reserved.