Holdenried‐Chernoff, D, Maffei, S orcid.org/0000-0002-1603-4040 and Jackson, A (2020) The Surface Expression of Deep Columnar Flows. Geochemistry, Geophysics, Geosystems. ISSN 1525-2027
Abstract
Studies of the Earth's secular variation have blossomed in recent decades, due to the availability of brand‐new satellite data. In particular, flow inversions at the core surface that incorporate the effects of rapid rotation a priori have been able to provide new insight into flows with time scales as short as a few years. These models have been mostly developed in a cylindrical representation, while core inversion methods are based on a spherical surface representation of the flow. This technical brief links band‐limited expressions for the flow coefficients in a cylindrical representation and those in a spherical surface representation, and demonstrates that these also remain band‐limited, with equal degrees of freedom. Correct regularity conditions on the stream function ensure a regular representation of these flows on the spherical surface. A triangular truncation rule for the cylindrical representation that is applicable for “isotropic resolution” is also presented. The equations we derive will be of use in future data‐assimilation work employing this cylindrical flow representation, and may prove helpful for conventional core‐inversion strategies.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Keywords: | Quasi‐geostrophic approximation; Columnar flow; Core‐flow inversion |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Environment (Leeds) > School of Earth and Environment (Leeds) > Inst of Geophysics and Tectonics (IGT) (Leeds) |
Funding Information: | Funder Grant number NERC (Natural Environment Research Council) NE/P016758/1 |
Depositing User: | Symplectic Publications |
Date Deposited: | 01 May 2020 13:32 |
Last Modified: | 01 May 2020 13:32 |
Status: | Published online |
Publisher: | American Geophysical Union |
Identification Number: | 10.1029/2020gc009039 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:160096 |