Abstract:
A combined uniform and long-time series of Ca-K images from the Kodaikanal Observatory, Mount Wilson
Observatory and Mauna Loa Solar Observatory was used to identify and study the Ca-K small-scale features and
their solar cycle variations over a century. The small scale features are classified into three distinct categories:
enhanced network, active network and quiet network. All these features show that their areas vary according to the
11 yr solar cycle. The relative amplitude of the Ca-K network variations agrees with that of the sunspot cycle. The
total area of these small-scale features varies from about 5% during the minimum phase of the solar cycle to about
20% during its maximum phase.
