NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Latitudinal Transport of Angular Momentum by Cellular Flows Observed with MDIWe have analyzed Doppler velocity images from the MDI instrument on SOHO to determine the latitudinal transport of angular momentum by the cellular photospheric flows. Doppler velocity images from 60-days in May to July of 1996 were processed to remove the p-mode oscillations, the convective blue shift, the axisymmetric flows, and any instrumental artifacts. The remaining cellular flows were examined for evidence of latitudinal angular momentum transport. Small cells show no evidence of any such transport. Cells the size of supergranules (30,000 km in diameter) show strong evidence for a poleward transport of angular momentum. This would be expected if supergranules are influenced by the Coriolis force, and if the cells are elongated in an east-west direction. We find good evidence for just such an east-west elongation of the supergranules. This elongation may be the result of differential rotation shearing the cellular structures. Data simulations of this effect support the conclusion that elongated supergranules transport angular momentum from the equator toward the poles, Cells somewhat larger than supergranules do not show evidence for this poleward transport. Further analysis of the data is planned to determine if the direction of angular momentum transport reverses for even larger cellular structures. The Sun's rapidly rotating equator must be maintained by such transport somewhere within the convection zone.
Document ID
20010038455
Acquisition Source
Marshall Space Flight Center
Document Type
Conference Paper
Authors
Hathaway, David H.
(NASA Marshall Space Flight Center Huntsville, AL United States)
Gilman, Peter A.
(National Center for Atmospheric Research Boulder, CO United States)
Beck, John G.
(Stanford United States)
Rose, M. Franklin
Date Acquired
August 20, 2013
Publication Date
January 1, 2001
Subject Category
Fluid Mechanics And Thermodynamics
Meeting Information
Meeting: American Geophysical Union Spring Meeting
Location: Boston, MA
Country: United States
Start Date: May 30, 2001
Sponsors: American Geophysical Union
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

Available Downloads

There are no available downloads for this record.
No Preview Available