摘要：

Cavity Ring-down Spectroscopy (CRDS) has been widely used in novel methods for high-frequency, shipboard measurements of important biogeochemical properties and fluxes in the ocean. Two latest CRDS-based systems, i.e., the Ultra-high Precision Dissolved Inorganic Carbon Analyzer (UP-DICA), and the Marine Acetylene Reduction Assay Cavity ring-down laser Absorption Spectroscopy (MARACAS) will be introduced and discussed. The UP-DICA employs the double isotope dilution technique, and continuously measures DIC concentration in the surface ocean with the relative precision < 0.03%. maracas takes the advantage of high-sensitivity of crds analyzers and the conventional acetylene reduction assay. it can be used for fully continuously monitoring of n₂ fixation rate in culture experiments, or for measuring of N₂ fixation rate in the field at ~30 minute/sample. Successful developments of these systems exemplify a general path that can be followed to derive high-frequency and underway observational systems based on CRDS.

Introduction of the speaker

Kuan Huang got his Ph. D. in Chemical Oceanography from Princeton University in 2013, and was then appointed as a NOAA/UCAR Climate and Global Change Post-doctoral Fellow. While finishing his post-doctoral research, Dr. Huang also serves as an Application Scientist at Picarro Inc., the leading provider of trace gas and stable isotope analyzers for environmental studies. Dr. Huang’s major interest is to develop and apply novel methods for automatic, high-frequency measurements to facilitate the studies of global carbon, nitrogen and oxygen cycles. His past experience includes studies of biological productivities in high-latitude oceans, development of underway DIC analyzers, and development of new methods for marine N₂ fixation studies.