ANR MARCARA

International collaborative research project (ANR PRCI) with the Alfred Wegener Institute in Bremerhaven (Helmholtz Centre) on the subject of radiocarbon age variability in the marine reservoir and its implications for paleoceanography, paleoclimatology and geochronology.

The 14C age of the marine surface reservoir (MRS) is a tracer of air-sea gas exchange and carbon mixing in the ocean. These processes are linked to climate, ocean and carbon cycle parameters that have varied over the last 50,000 years.

The MARCARA project focuses on the observation and numerical modelling of the MRA for key sites in the major oceans. We are measuring 14C ages on micro-samples using the AixMICADAS spectrometer equipped with its multipurpose ion source (solid & gas). This allows us to better quantify the MRA and to avoid, or correct, certain biases.

Our German partners use numerical models based on a high resolution unstructured mesh approach to zoom in on regions of interest, with assimilation of marine and atmospheric 14C data.

The MARCARA project focuses on the last deglaciation and abrupt climate changes such as the Heinrich and Dansgaard-Oeschger events, whose role in the carbon cycle is still poorly understood.