Jean Jouzel (Janzé, Ille-et-Vilaine, France, 1947) obtained his engineering degree from the École Supérieure de Chimie Industrielle de Lyon (1968), going on to earn a PhD in Physical Sciences there in 1974. In 1973, he joined the French Alternative Energies and Atomic Energy Commission (CEA) as a research scientist. Today he is a CEA emeritus scientist at the Laboratoire des Sciences du Climat et de l’Environnement, a joint initiative of the CEA, the French National Center for Scientific Research (CNRS) and Université Paris-Saclay. Jouzel was a lead author on the second and third reports of the Intergovernmental Panel on Climate Change and served as vice-chair of its Working Group I. He is also a past director of the Institute Pierre-Simon Laplace, which brings together the expertise of eight laboratories, two associated teams and 1,500 professionals working in climate and environmental research. Jouzel is a Member Editor of the Proceedings of the National Academy of Sciences.
An ice core is a cylindrical sample obtained by drilling into the substrate at different depths. Jean Jouzel’s analysis of one such core from the Antarctic base of Vostok, written up in a Nature paper of 1987, brought definitive proof that increased atmospheric concentrations of carbon dioxide lead to an increase in temperature. Although physics-based climate models showing this effect had existed since the 1960s, ice cores brought a whole new dimension to climate science by providing concrete data on the composition of the atmosphere throughout geological history. Work with these cores had begun in the 1980s, but none of the records obtained stretched further back than the last ice age. However, Soviet scientists stationed at Vostok were able to extract a longer core giving a temperature record of 160,000 years; the first time samples could be obtained from the previous interglacial period. With this material, Jouzel was able to demonstrate a close linkage between variations in the carbon cycle, atmospheric composition and climate, three key factors in the dynamics of glacial-interglacial cycles.