Meridional Motions and Reynolds Stress Determined by Using Kanzelhöhe Drawings and White Light Solar Images from 1964 to 2016
arXiv:1804.01344 · doi:10.1007/s11207-018-1286-5
Abstract
Sunspot position data obtained from Kanzelhöhe Observatory for Solar and Environmental Research (KSO) sunspot drawings and white light images in the period 1964 to 2016 were used to calculate the rotational and meridional velocities of the solar plasma. Velocities were calculated from daily shifts of sunspot groups and an iterative process of calculation of the differential rotation profiles was used to discard outliers. We found a differential rotation profile and meridional motions in agreement with previous studies using sunspots as tracers and conclude that the quality of the KSO data is appropriate for analysis of solar velocity patterns. By analysing the correlation and covariance of meridional velocities and rotation rate residuals we found that the angular momentum is transported towards the solar equator. The magnitude and latitudinal dependence of the horizontal component of the Reynolds stress tensor calculated is sufficient to maintain the observed solar differential rotation profile. Therefore, our results confirm that the Reynolds stress is the dominant mechanism responsible for transport of angular momentum towards the solar equator.
arXiv comment14 pages, 6 figures
References in corpus (12)
- Reynolds stress and heat flux in spherical shell convection
- Kodaikanal Digitized White-light Data Archive (1921-2011): Analysis of various solar cycle features
- Validity of the relations between the synodic and sidereal rotation velocities of the Sun
- Steps toward a high precision solar rotation profile: Results from SDO/AIA coronal bright point data
- Solar differential rotation in the period 1964 - 2016 determined by the Kanzelhöhe data set
- Characterizing the feedback of magnetic field on the differential rotation of solar-like stars
- Tracing sunspot groups to determine angular momentum transfer on the Sun
- Effects of Solar Active Regions on Meridional Flows
- Meridional Motion and Reynolds Stress from Debrecen Photoheliographic Data
- Meridional motions and Reynolds stress from SDO/AIA coronal bright points data
- Solar Dynamics, Rotation, Convection and Overshoot
- Automated sunspot detection and the evolution of sunspot magnetic fields during solar cycle 23