Professor Dr Edouard Bard

Research Priorities: Climate, oceanography, paleoclimate, paleoceanography, geochemistry
Edouard Bard is a French climate researcher who works at the interface of climatology, oceanography, and geology. He examines how oceans, atmospheres, ice masses, and living organisms are linked to each other and how this system reacts over periods ranging from decades to millions of years. This long-term overview of climate events makes it possible to determine which events have geological or astronomical causes and which are anthropogenic in origin.
For this research, Edouard Bard uses techniques of analytical chemistry to determine the extent and timing of climatic variations. With these processes he analyses various natural archives, in which information about the climate of the past is stored. The spectrum ranges from sediments on ocean or lake floors to corals, stalagmites, and polar ice. His aim is to use complementary methods to study phenomena such as ice ages and to thus obtain the most realistic picture possible of the processes that took place at those times.
His studies of drill cores from the ocean floor at various locations show, for example, that at times in the past surface water either warmed or cooled very quickly. Rapid changes of several degrees Celsius per century have been demonstrated, which broadly corresponds to the changes that experts anticipate in the coming century.
One of the most important tools Edouard Bard uses is the analysis of isotopes – species of atoms of the same chemical element with different atomic masses. In the 1980s he was involved in the development of accelerator mass spectrometry, which makes it possible to quantify the carbon isotope 14C (radiocarbon) even in small samples. Using these and other techniques, he and his team managed to more precisely date and understand the events recorded in the climate archives.
Edouard Bard studied past sea levels by dating with uranium and thorium isotopes the reefs near Barbados and Tahiti. In the period from approximately 21,000 to 6,000 years ago, as the glaciers of the last ice age gradually receded, he showed that sea levels changed by more than one hundred meters, at rates that sometimes exceeded several metres per century.
By means of the carbon isotope 14C it was possible to trace carbon dioxide of anthropogenic origin and gain new insights into changes in sea currents and the global carbon cycle. Furthermore, the comparison of both dating methods – U-Th and 14C – showed that the radiocarbon method systematically underestimated the age of the samples by several thousand years. The radiocarbon method is widely used to determine the age of wood, bones, textiles, and numerous other materials, this is an important finding. Edouard Bard’s results were incorporated into computer programmes, by means of which it is possible to calibrate the results of radiocarbon dating.
In summary, Edouard Bard can document and date changes in atmospheres and oceans. This allows him to identify and understand underlying mechanisms. In this way, studying the past can help predict future climate development.