Abstract
In this paper we study upwelling pathways and timescales of Circumpolar Deep Water (CDW) in a hierarchy of models using a Lagrangian particle tracking method. Lagrangian timescales of CDW upwelling decrease from 87 years to 31 years to 17 years as the ocean resolution is refined from 1° to 0.25° to 0.1°. We attribute some of the differences in timescale to the strength of the eddy fields, as demonstrated by temporally degrading high-resolution model velocity fields. Consistent with the timescale dependence, we find that an average Lagrangian particle completes 3.2 circumpolar loops in the 1° model in comparison to 0.9 loops in the 0.1° model. These differences suggest that advective timescales and thus interbasin merging of upwelling CDW may be overestimated by coarse-resolution models, potentially affecting the skill of centennial scale climate change projections.
Original language | English (US) |
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Pages (from-to) | 891-898 |
Number of pages | 8 |
Journal | Geophysical Research Letters |
Volume | 45 |
Issue number | 2 |
DOIs | |
State | Published - Jan 28 2018 |
All Science Journal Classification (ASJC) codes
- Geophysics
- General Earth and Planetary Sciences
Keywords
- Circumpolar Deep Water
- Southern Ocean
- eddy parameterization
- meridional overturning circulation
- ocean modeling
- upwelling