The solar polar regions play a critical role in the solar dynamo and activity cycle. Magnetic field of active regions is transported by meridional flows from low latitudes to the polar regions. This flux transport causes reversals of the global magnetic field of the Sun around the time of activity maxima. The amount of magnetic flux accumulated in the polar regions determines the strength of the future sunspot cycle. For understanding the mechanism of the cyclic magnetic activity it is very important to measure the properties of the meridional flows and supergranular dynamics in the high-latitude regions, and their variations during the solar cycle.
The current observations from SOHO/MDI and future observations from SDO/HMI cannot resolve the near polar regions due to foreshortening and the relatively low resolution. Hinode/SOT provides a unique opportunity to investigate the dynamics of the near-polar regions and measure the speed of high-latitude meridional flows and their variations during various periods of the solar cycle. These observations are best done during the periods of the high inclinations of the Sun’s axis, 2-10 March and 3-11 September, every year.
We propose helioseismology observations of the polar regions during 2-10 March and 3-11 September, every year. The observing runs must be at least 16 hour long, but longer continuous observations are highly desirable for investigation of the supergranular dynamics and short term variatio |
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