Measuring natural isotopes accurately
In her dissertation, Anita Aerts-Bijma takes readers into the fascinating world of isotope research – where scientists study tiny variations in atoms to learn more about our planet’s history. Her work at the Centre for Isotope Research (CIO) focuses on improving the accuracy of these delicate measurements.The first part of the research looks at radiocarbon (¹⁴C), best known for dating archaeological materials such as wood or bone.
Getting precise results requires careful control of every single step, from preparing the samples to running the final analyses. Aerts-Bijma's work identifies where small inaccuracies can arise and how these can be reduced, helping ensure radiocarbon ages are as reliable as possible.The next two studies focus on stable oxygen isotopes (¹⁸O) found in water and in calcium-carbonate materials like shells. These isotopes provide valuable clues about past climate conditions.
However, one of the key international reference materials used to define the ¹⁸O water scale — known as SLAP — turned out to have a slightly incorrect value. Through clever mixing experiments and refined analytical techniques, Anita was able to determine a more accurate value for this standard.
Finally, she achieved something that had never before been done with such precision: directly linking the ¹⁸O measurement scales for water and for carbonates. This breakthrough allows climate and environmental scientists worldwide to compare their results with greater confidence and consistency. Altogether, Aerts-Bijma’s dissertation makes a significant contribution to the global effort to make isotope measurements ever more precise — a crucial step toward understanding the Earth’s climate, environment, and history in finer detail.