Water isotope variations in the global ocean model MPI-OM
The stable water isotopes (H2O)-O-18 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 delta O-18 and delta D distributions at the ocean surface and deep ocean are g...
Published in: | Geoscientific Model Development |
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Main Authors: | , , , |
Format: | Text |
Language: | English |
Published: |
Copernicus Gesellschaft Mbh
2012
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Subjects: | |
Online Access: | https://doi.org/10.5194/gmd-5-809-2012 https://archimer.ifremer.fr/doc/00383/49455/49910.pdf https://archimer.ifremer.fr/doc/00383/49455/49911.pdf https://archimer.ifremer.fr/doc/00383/49455/ |
Summary: | The stable water isotopes (H2O)-O-18 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 delta O-18 and delta D distributions at the ocean surface and deep ocean are generally consistent with available observations on the large scale. The modelled delta D-delta O-18 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 degrees S and 55 degrees N, and a strong decrease north of 55 degrees N. The model is also able to capture the quasi-linear relationship between delta O-18 and salinity S, as well as delta D and S, as seen in observational data. Both in the model results and observations, the surface delta-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. |
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