Atmospheric chemistry and biogeochemical material cycles traced by innovative measurement of isotopic substituted molecules
Like all elements are composed of isotopes, all molecules are composed of many isotopically substituted species (abbreviated as isotopomer here, another candidate is isotopologue), but most isotopomers cannot be measured accurately yet. Dr. Naohiro Yoshida’s main research achievements include development of methodologies for accurately determining the natural abundance of various isotopomers, and elucidating the origin of those molecules to understand the global environment, the origin and evolution of the earth and life. As an example of inorganic molecules, the isotope ratio and the isotope molecular ratio of nitrous oxide were measured for the first time in the world, and it was clarified that nitrous oxide is greatly involved in global warming and ozone depletion, its origin and future trends. As examples of low-molecular organic compounds, he has developed methods for measuring isotopomers of hydrocarbons and low-molecular amino acids, and has made important discoveries about the origins and processes of biomarkers such as metabolism of organisms, processes of bio/abio-degradation in strata, and inorganic synthesis, which lead to the significant findings for the origin and processes for these important biomarkers. In addition, he has created new global standards in the development of measurement methodologies and led international calibration, and has been leading international collaborative researches in environmental observation and simulation experiments in applying measurement methods. These series of studies are innovative and outstanding in the field of global environmental chemistry.