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 present the analysis of temperature variations in Portugal for 140 years(from 1865 to 2005). The two stations with the longest time series oftemperature measurements (Lisbon and Coimbra) have been used to study thedependence of the portuguese climate variations on the changes of both globalcirculation and solar activity. Monthly averaged temperature series have beenanalyzed together with monthly North-Atlantic Oscillation index data, sunspotnumbers and cosmic ray flux intensity. Different statistical methods (thecorrelation analysis and the multiple regression analysis) were used. Ourresults show that the temperature in Portugal depends not only on theatmospheric variations in the studied region but also on the variations of thesolar parameters such as sunspot numbers and the cosmic rays flux intensity.Also, the dependence of temperature on solar parameters is strong during thecold season (November to February), while much weaker during the warm season.For some months, strong correlations between the temperature variations of thecurrent month and the North-Atlantic Oscillation index values of the previousmonth have been found. The correlation between climatic and solar parametersshows up best on the decadal and decadal-to-centennial timescale. It is foundthat the temperature correlates positively with the sunspot numbers andnegatively with the CR flux intensity throughout the year. Besides, theabsolute values of the correlation coefficients between the temperature and theCR are higher than those between the temperature and the sunspot numbers. Ourresults are consistent with some of the proposed mechanisms that relate solaractivity to Earth climate and could be explained through the effect of thesolar UV radiation and stratosphere-troposphere coupling or/and through theeffect of the CR particles on clouds and stratospheric and troposphericconditions.

Long-time temperature variations in Portugal over the last 140 years and the effect of the solar activity