CosgroveForbes-MNRAS-Saturn2017.pdf (2.67 MB)
A δ-plane simulation of anticyclones perturbing circumpolar flows to form a transient north polar hexagon
journal contribution
posted on 2023-05-19, 10:34 authored by Jason CosgroveJason Cosgrove, Lawrence ForbesLawrence ForbesSaturn's North Polar Hexagon was discovered by Godfrey who pieced together map projections of images captured by the Voyager mission to unveil a hexagonal structure over the north pole of Saturn. This article attempts to answer whether or not a hexagonal structure can be formed through anticyclones impinging on the dominant eastward circumpolar flow and is in part based upon the proposed theory by Allison et al. that the Hexagon may be the result of at least one impinging anticyclone perturbing a circumpolar jet centrally located around the 76°N latitude. A high-latitude δ-plane approximation is used to simulate the interaction between an initially circular circumpolar jet and at least one perturbing anticyclone. Our simulations with one perturbing anticyclone failed to form a hexagonal structure; yet by including an additional anticyclone it was found that depending on the strength, location and radius of the perturbing anticyclones a hexagonal feature could develop. However, the longevity and drift rate of the actual Hexagon must be attributed to other factors not considered in this paper.
History
Publication title
Monthly Notices of the Royal Astronomical SocietyVolume
469Issue
4Pagination
4133-4147ISSN
0035-8711Department/School
School of Natural SciencesPublisher
Blackwell Publishing LtdPlace of publication
9600 Garsington Rd, Oxford, England, Oxon, Ox4 2DgRights statement
This article has been accepted for publication in Royal Astronomical Society. Monthly Notices. Copyright 2017 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.Repository Status
- Open