Journal cover Journal topic
Geoscientific Model Development An interactive open-access journal of the European Geosciences Union
Geosci. Model Dev., 5, 809-818, 2012
© Author(s) 2012. This work is distributed under
the Creative Commons Attribution 3.0 License.
Model experiment description paper
05 Jun 2012
Water isotope variations in the global ocean model MPI-OM
X. Xu1, M. Werner1, M. Butzin2,1, and G. Lohmann1 1Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany
2MARUM-Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
Abstract. The stable water isotopes H218O and HDO are incorporated as passive tracers into the oceanic general circulation model MPI-OM, and a control simulation under present-day climate conditions is analyzed in detail. Both δ18O and δD distributions at the ocean surface and deep ocean are generally consistent with available observations on the large scale. The modelled δD-δ 18O relations in surface waters slightly deviates from the slope of the global meteoric water line in most basins, and a much steeper slope is detected in Arctic Oceans. The simulated deuterium excess of ocean surface waters shows small variations between 80° S and 55° N, and a strong decrease north of 55° N. The model is also able to capture the quasi-linear relationship between δ18O and salinity S, as well as δD and S, as seen in observational data. Both in the model results and observations, the surface δ−S relations show a steeper slope in extra-tropical regions than in tropical regions, which indicates relatively more addition of isotopically depleted water at high latitudes.

Citation: Xu, X., Werner, M., Butzin, M., and Lohmann, G.: Water isotope variations in the global ocean model MPI-OM, Geosci. Model Dev., 5, 809-818,, 2012.
Publications Copernicus