Ikerbasque Research Professor at the Basque Centre for Climate Change (BC3) and Ikerbasque, the Basque Foundation for Science (Spain). He is a physicist with a PhD from the Technical University of Darmstadt, Germany (2003). He is also the director of the low-temperature laboratory IzotzaLab, leader of the Physical Basis research line, and director of the Cryosphere and Climate Modelling research groups at BC3. He is the lead and a contributing author to the Sixth Assessment Report (AR6) Working Group 1 (WGI), of the Intergovernmental Panel on Climate Change (IPCC) and editor of Journal of Glaciology (Cambridge University Press) and Scientific Reports (Nature Publishing Group). He has also participated in several expeditions to the most remote glaciers at the heart of Antarctica and Greenland.