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

In this work, we use two decadal sunspot number series reconstructed fromcosmogenic radionuclide data (14C in tree trunks, SN-14C and 10Be in polar ice,SN-10Be) and the Extreme Value Theory to study variability of solar activityduring the last 9 millennia. The peaks-over-threshold technique was used tocompute, in particular, the shape parameter of the generalized Paretodistribution for different thresholds. Its negative value implies an upperbound of the extreme SN-10Be and SN-14C time series. The return level for 1000and 10000 years were estimated leading to values lower than the maximumobserved values, expected for the 1000-year, but not for the 10000-year returnlevels, for both series. A comparison of these results with those obtainedusing the observed sunspot numbers from telescopic observations during the lastfour centuries suggest that the main characteristics of solar activity havealready been recorded in the telescopic period (from 1610 to nowadays) whichcovers the full range of solar variability from a Grand minimum to a Grandmaximum.

Extreme value theory applied to the millennial sunspot number series