Peru hosts a significant portion of the world’s tropical glaciers, which are undergoing rapid mass loss due to climate change. Knowledge of the ice volume and bedrock topography of these glaciers is important for predicting changes in glacier dynamics, runoff, and interpreting ice-core records. This study presents results from glaciological and geophysical surveys conducted during a 2019 expedition to Nevado Huascarán, Peru’s highest mountain when four ice cores were extracted from the col and summit. Ground-penetrating radar measurements provided detailed ice thickness and snow accumulation data, highlighting complex internal glacier structure and indicated that the climatic records obtained from ice cores recovered in 2019 were continuous and extended past the Holocene. Ice flow modeling enabled investigation of glacier dynamics. It was shown that the upstream effect on ice-core record is minimal. Comparison with ice thickness modeling data for Huascarán from various sources revealed significant discrepancies with measured ice thicknesses, suggesting that the inversion methods underestimate ice thickness for the accumulation zones of mountain glaciers. This research contributes data for understanding glacier behavior in the context of climate change and for modeling efforts for better assessments of water resources, potential geohazards and paleoclimatic interpretations.

Despite their high value and importance for various glaciological applications, detailed ice thickness measurements of alpine glaciers are still very limited. Knowledge of bedrock topography is essential for paleoglaciological studies. The Guliya ice cap located on the Tibetan Plateau is one of the highest and largest ice caps in mid-low latitude regions. A detailed ground-penetrating radar (GPR) survey was conducted on the Guliya ice cap in 2015 using 20 and 40 MHz frequency antennas. An empirical Bayesian kriging method was used for ice thickness interpolation and uncertainty assessment. GPR measurements revealed complex basal topography of the Guliya glacier with a maximum thickness of 371.12 ± 13 m. The internal reflections caused by changes in the dielectric properties were registered on the 40 MHz radargrams at the summit and were attributed to density variations. As a result of this fieldwork, one of the largest ice thickness datasets in High Mountain Asia was obtained. Guliya glacier elevation changes were assessed by differencing digital elevation models. The glacier gained mass from 2000 to 2015 with an average rate of 0.270 ± 0.11 m w.e. a−1 at the summit and 0.279 ± 0.11 m w.e. a−1 at the lower elevations.