Influence of Non-seasonal Discharge on Global Ocean State
Abstract
Continental rivers, serving as a critical branch of the global water cycle, provide some of largest point-sources of freshwater flux into the ocean. Recent studies from remote sensing observations find that the interannual variability in discharge is capable of having large influences on sea surface salinity (SSS) and sea surface height (SSH). However, owing to difficulty in measurement, river discharge is not a well-represented input to the current global ocean models, with most freshwater forcing datasets using climatological discharge. A new daily-varying discharge forcing dataset JRA55-do raises questions on whether inclusion of non-seasonal variability in discharge provides a quantifiable impact on the ocean state, and whether the new forcing can help improve the model skill in representing variability in SSS and SSH against observations. We address these questions by conducting sensitivity experiments with a high-resolution global ocean general circulation model. We find that non-seasonal variability in discharge has a detectable impact on SSS and SSH over several major river plume regions, and that forcing of daily-varying discharge improves model state's comparison against remote sensing observations at interannual timescales.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFMGC43J1377W
- Keywords:
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- 1616 Climate variability;
- GLOBAL CHANGE;
- 1655 Water cycles;
- GLOBAL CHANGE;
- 1836 Hydrological cycles and budgets;
- HYDROLOGY;
- 4215 Climate and interannual variability;
- OCEANOGRAPHY: GENERAL