English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We use the historic record of sunspot groups compiled by the Royal GreenwichObservatory together with the sunspot number to derive the statisticalproperties of sunspot group emergence in dependence of cycle phase andstrength. In particular we discuss the latitude, longitude, area and tilt angleof sunspot groups as functions of the cycle strength and of time during thesolar cycle. Using these empirical characteristics the time-latitude diagram ofsunspot group emergence (butterfly diagram) is reconstructed from 1700 onwardon the basis of the Wolf and group sunspot numbers. This reconstruction will beuseful in studies of the long-term evolution of the Sun's magnetic field.

The solar magnetic field since 1700: I. Characteristics of sunspot group emergence and reconstruction of the butterfly diagram