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 Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We study a possible relationships between seasonal distributions of thevisually observed cloudless days (CD) and cloudless nights (CN) at AbastumaniAstrophysical Observatory (41.75N, 42.82E; Georgia) in 1957-1993. The annualvariations of monthly numbers of CD and CN have been observed, with maximum inAugust for CD and in September for CN. During geomagnetic disturbances it isalso observed the growth of number of CD in September andMarch (equinoctialmonths), and for CN, together with September, in June, April and February. Weassume that this phenomenon indicates an influence of cosmic factors oncloudiness, as well as the existence of semiannual and possiblyshorter-periodicity variations. This cosmic factor can be the manifestation ofdifferent rates of the galactic cosmic rays (GCRs) flux variations in CD and CNperiods. The influence of GCR flux on ionization of lower atmosphere andvariations of density of cloud condensation nuclei also can be connected to theannual and seasonal changes of temperature at Earth surface of this region. Tocomprehend behaviors of the annual and semi-annual variations of the GCRintensity and their possible relationships with the seasonal distributions ofCD and CN we compose and numerically solve two dimensional (2-D) time dependenttransport equation including all important processes in the heliosphere. Ananalysis of experimentally observed and theoretically obtained results havebeen carried out.

Annual Variations of the Galactic Cosmic Ray Intensity and Seasonal  Distribution of the Cloudless Days and Cloudless Nights in Abastumani  (41.75oN, 42.82oE; Georgia): (1) experimental study and (2) theoretical  modeling