We have analyzed the Ca-K images obtained at Kodaikanal Observatory as a function of latitude and time for the period of 1913 – 2004 covering Solar Cycles 15 to 23. We have classified the chromospheric activity into plage, Enhanced Network (EN), Active Network (AN), and Quiet Network (QN) areas to differentiate between large strong active and small weak active regions. The strong active regions represent toroidal and weak active regions poloidal component of the magnetic field. We find that plage areas mostly up to \(50^{\circ }\) latitude belt vary with about 11-year solar cycle. We also find that a weak activity represented by EN, AN and QN varies with about 11-year with significant amplitude up to about \(50^{\circ}\) latitude in both hemispheres. The amplitude of the variation is minimum around \(50^{\circ }\) latitude and again increases by a small amount in the polar region. In addition, the plots of plages, EN, AN and QN as functions of time indicate the maximum of activity at different latitude occur at different epoch. To determine the phase difference for the different latitude belts, we have computed the cross-correlation coefficients of other latitude belts with the \(35^{\circ }\) latitude belt. We find that the activity shifts from mid-latitude belts towards equatorial belts at high speed at the beginning of a solar cycle and at lower speed as the cycle progresses. The speed of the shift varies between \(\approx19\) and \(3~\text{m}\,\text{s}^{-1}\) considering all the data for the observed period. This speed can be linked with the speed of meridional flows, believed to occur between convection zone and the surface of the Sun.

我们分析了1913年至2004年期间在Kodaikanal天文台获得的Ca-K图像作为纬度和时间的函数，涵盖了太阳周期15至23。 （AN）和安静网络（QN）区域，以区分大型强活动区域和小型弱活动区域。强有源区代表磁场的环形和弱有源区的极向分量。我们发现，主要到\（50 ^ {\ circ} \）纬度带的小片区域随太阳周期约11年的变化而变化。我们还发现，以EN，AN和QN表示的微弱活动大约持续11年，且幅度大到大约\（50 ^ {\ circ} \）在两个半球的纬度。变化的幅度在\（50 ^ {\ circ} \）纬度附近最小，并且在极地区域再次少量增加。此外，随时间变化的EN，AN和QN曲线图表明，不同纬度的活动最大值发生在不同时期。为了确定不同纬度带的相位差，我们计算了其他纬度带与\（35 ^ {\ circ} \）纬度带的互相关系数。我们发现，活动在太阳周期开始时从中纬度带向赤道带转移，随着太阳活动的进行，其活动速度降低。移位的速度在\（\ approx19 \）和\（3〜\ text {m} \，\ text {s} ^ {-1} \）考虑了观察期内的所有数据。该速度可以与子午流的速度相关联，认为子午流的速度发生在对流区和太阳表面之间。