The Earth''s climate has varied naturally throughout its history. Knowledge of these past variations and their dynamics is crucial for predicting future climate change. Reconstructing past climate variability is based on natural climate archives with ice cores being one of the most prominent archives in use. This study presents the results of ice cores retrieved from three different glaciers in the Andes and the Alps. Two glaciers in the Andes were sampled, assuming they represented a potential archive of past ENSO (El Niño-Southern Oscillation) variability. The glacier at Plomo was found to be strongly influenced by melt water percolation whereas the signal of chemical tracers and stable isotopes at the glacier near Mercedario was well preserved. The third glacier studied was Colle Gnifetti in the Alps. This ice core was found to be more than 11700 years old and contained ice from the last Ice Age. Chemical tracers like sulphate impressively document the history of anthropogenic air pollution since the beginning of industrialization.