The research line of José María Fernández is framed within the field of Environmental Sciences and has focused on the cryosphere and the study of the glacial dynamics and postglacial environmental evolution in cold-climate areas (high mountains and Polar Regions), which are especially vulnerable to climate fluctuations. Indeed, changes in these regions may have profound consequences at global scale. His scientific background has provided him a better understanding of the interactions between glaciers and climate variability, as well as their spatio-temporal patterns based on a multidisciplinary approach integrating a number of methodologies. Among them, geomorphological mapping of glacial landforms allowed him to reconstruct the geometry and extent of glaciers in different past cold and warm periods. From this information, he has performed three-dimensional palaeoglacier reconstructions based on physical-based numerical models in order to estimate ice thicknesses and volumes during past stages and to infer glaciological parameters linked to climate, with the potential of quantifying past temperature and precipitation variations. With this approach, he reconstructed glacial fluctuations at diverse timescales and assessing whether current glacier variations were of similar magnitude in the past or the recent climatic trend is unprecedented in the geological record. The applicant has acquired a solid experience in the application of cosmic-ray surface exposure dating thanks to its training during 6 research stays (10 months) in world leading research centers, such as the Centre Européen de Recherche et d’Enseignement des Géosciences de l’Environnement (France). His expertise in the application of this technique in different areas led him to collaborate in the development of the chronology of glacial oscillations since the Last Glacial Maximum (LGM; ~20,000 years ago), in parallel with the daily duties at the university as PhD student and post-doctoral researcher. The long experience of the applicant in the application of this techniques is supported also by a number of field work campaigns, including Northern Iceland (Tröllaskagi Peninsula, i.e. the study area of his PhD Thesis), where he reconstructed the deglaciation process in various valleys and carried out palaeoclimatic reconstructions. Together with the subpolar regions, since 2019 the applicant focuses his research on the study of the deglaciation in ice-free areas of the Antarctic Peninsula since the LGM. In parallel, he has complemented these activities with research conducted in other mountain areas of the Iberian Peninsula (Central Range, NW Ranges, Iberian Range and Pyrenees), reconstructing the spatio-temporal patterns of glacial oscillations during the Last Glacial Cycle. Recently, he has also joined a research project focused on the deglaciation in Greenland. His research excellence in the last years is reflected in 17 papers published in indexed journals (15, last 3 years), over 30 communications in national and international conferences, the co-edition of a reference book in the glacial landscape studies (“Iberia, land of glaciers”) and his co-authoring several book chapters related to this topic. Moreover, it is noteworthy that the applicant has complemented this activities with talks and teaching activities at international universities (Universidad Complutense de Madrid). He is also member of the international association PYRN (Permafrost Young Rresearchers Network).