{"id":28110,"date":"2015-07-12T18:58:18","date_gmt":"2015-07-12T16:58:18","guid":{"rendered":"https:\/\/ocasapiens-dweb.blogautore.repubblica.it\/?p=28110"},"modified":"2021-10-17T19:36:52","modified_gmt":"2021-10-17T17:36:52","slug":"mini-era-glaciale","status":"publish","type":"post","link":"https:\/\/archivio.ocasapiens.org\/index.php\/2015\/07\/12\/mini-era-glaciale\/","title":{"rendered":"Mini-era glaciale?"},"content":{"rendered":"<p style=\"text-align: left;\"><img decoding=\"async\" src=\"http:\/\/bxhorn.com\/wp-content\/uploads\/2013\/12\/Plot133a.png\" alt=\"\" \/>Oltre alle previsioni dei globalcoolisti sull&#8217;era glaciale iniziata nel 1999 e rimandata di anno in anno, si <a href=\"http:\/\/science.nasa.gov\/science-news\/science-at-nasa\/2006\/10may_longrange\/\" target=\"_blank\" rel=\"noopener\">susseguono<\/a> quelle di scienziati d.o.c. su un <a href=\"http:\/\/rspa.royalsocietypublishing.org\/content\/466\/2114\/303\" target=\"_blank\" rel=\"noopener\">minimo<\/a> di <a href=\"http:\/\/news.nationalgeographic.com\/news\/2011\/06\/110614-sun-hibernation-solar-cycle-sunspots-space-science\/\" target=\"_blank\" rel=\"noopener\">attivit\u00e0 solare<\/a> pari a quello di Maunder dal 1645 al 1715 circa, durante il quale ci sono stati inverni gelidi in Europa e nel Nord-America.<\/p>\n<p style=\"text-align: left;\">I <a href=\"http:\/\/www.ilgiornale.it\/news\/cronache\/studio-sul-clima-sole-si-spegner-60-cento-nel-2030-1150706.html\" target=\"_blank\" rel=\"noopener\">globalcoolisti<\/a>\u00a0ci sperano, perch\u00e9 a loro avviso dimostrerebbe che il risc. glob. finito nel 1998 era tutto colpa\u00a0del<a href=\"https:\/\/www.skepticalscience.com\/solar-activity-sunspots-global-warming.htm\" target=\"_blank\" rel=\"noopener\"> Sole<\/a>, e sono ringalluzziti da un modello presentato dalla prof. Valentina Zharkova et al. all&#8217;assemblea della Royal Astronomical Society che ha prodotto titoli quali:<\/p>\n<ul>\n<li>Lo studio sul clima: &#8220;Il sole si spegner\u00e0 del 60 per cento nel 2030&#8221; (<a href=\"http:\/\/www.ilgiornale.it\/news\/cronache\/studio-sul-clima-sole-si-spegner-60-cento-nel-2030-1150706.html\" target=\"_blank\" rel=\"noopener\">Il Giornale<\/a>)<\/li>\n<li>Lo studio: tra il 2020 e il 2030 una mini-era glaciale (<a href=\"http:\/\/www.liberoquotidiano.it\/news\/scienze---tech\/11809688\/Lo-studio--tra-il-2020.html\" target=\"_blank\" rel=\"noopener\">Libero<\/a>)<\/li>\n<li>Rischio di mini-era glaciale nel 2030. Il Sole va a dormire (<a href=\"http:\/\/www.rainews.it\/dl\/rainews\/articoli\/Rischio-mini-era-glaciale-nel-2030-Il-Sole-va-a-dormire-f10922ff-63d1-48ef-8d0d-0568b567dadc.html\" target=\"_blank\" rel=\"noopener\">Rai News<\/a>)<\/li>\n<li>Tra 15 anni potrebbe iniziare una nuova Era Glaciale! (il meteorologo <a href=\"http:\/\/www.meteogiuliacci.it\/meteo\/articoli\/clima\/tra-15-anni-potrebbe-iniziare-una-nuova-era-glaciale\" target=\"_blank\" rel=\"noopener\">col. Giuliacci<\/a>&#8230;)<\/li>\n<li><img decoding=\"async\" class=\"aligncenter\" src=\"https:\/\/upload.wikimedia.org\/wikipedia\/commons\/thumb\/2\/28\/Sunspot_Numbers.png\/400px-Sunspot_Numbers.png\" alt=\"Solar cycle - Wikipedia\" \/><\/li>\n<\/ul>\n<p>Premessa. Come si vede dalla figura sopra e da <strong><a href=\"http:\/\/www.grandunification.com\/gifs\/Sunspots.gif\" target=\"_blank\" rel=\"noopener\">questa<\/a><\/strong>, la durata e l&#8217;intensit\u00e0 dei cicli solari variano. L&#8217;ipotesi prevalente \u00e8 che la variazione sia dovuta alla <a href=\"https:\/\/it.wikipedia.org\/wiki\/Dinamo_solare\" target=\"_blank\" rel=\"noopener\">dinamo solare<\/a> e alle sue turbolenze.<\/p>\n<p>Dal <a href=\"https:\/\/www.ras.org.uk\/news-and-press\/2680-irregular-heartbeat-of-the-sun-driven-by-double-dynamo\" target=\"_blank\" rel=\"noopener\">comunicato stampa<\/a> della RAS:<\/p>\n<p><em>Now, Zharkova and her colleagues have found that adding a second dynamo, close to the surface, completes the picture with surprising accuracy.<\/em><br \/>\n<em>\u201cWe found magnetic wave components appearing in pairs, originating in two different layers in the Sun\u2019s interior. They both have a frequency of approximately 11 years, although this frequency is slightly different, and they are offset in time.\u00a0 Over the cycle, the waves fluctuate between the northern and southern hemispheres of the Sun. Combining both waves together and comparing to real data for the current solar cycle, we found that our predictions showed an accuracy of 97%,\u201d said Zharkova.<\/em><br \/>\n<em>Zharkova and her colleagues derived their model using a technique called \u2018principal component analysis\u2019 of the magnetic field observations from the\u00a0<a href=\"http:\/\/wso.stanford.edu\/\">Wilcox Solar Observatory<\/a> in California. They examined three solar cycles-worth of magnetic field activity, covering the period from 1976-2008. In addition, they compared their predictions to average sunspot numbers, another strong marker of solar activity. All the predictions and observations were closely matched.\u00a0<\/em><\/p>\n<p>Le macchie solari sono <a href=\"http:\/\/science.nasa.gov\/media\/medialibrary\/2006\/05\/10\/10may_longrange_resources\/predictions3_strip.jpg\" target=\"_blank\" rel=\"noopener\">ancora pi\u00f9 variabili<\/a>\u00a0dei cicli e per ora non si riescono a <a href=\"http:\/\/solarscience.msfc.nasa.gov\/SunspotCycle.shtml\" target=\"_blank\" rel=\"noopener\">prevedere<\/a>.<\/p>\n<p><em>Looking ahead to the next solar cycles, the model predicts that the pair of waves become increasingly offset during Cycle 25, which peaks in 2022. During Cycle 26, which covers the decade from 2030-2040, the two waves will become exactly out of synch and this will cause a significant reduction in solar activity.<\/em><\/p>\n<p>Quando uscir\u00e0 l&#8217;articolo di Zharkova et al<em>. <\/em>si capir\u00e0 se il modello si basa su tre cicli soltanto, se \u00e8 stato tarato su quelli precedenti, perch\u00e9 il ciclo 25 avrebbe un picco dopo 3 anni invece di 5-6 ecc.<\/p>\n<p><em>\u201cIn cycle 26, the two waves exactly mirror each other \u2013 peaking at the same time but in opposite hemispheres of the Sun. Their interaction will be disruptive, or they will nearly cancel each other. We predict that this will lead to the properties of a \u2018<a href=\"https:\/\/en.wikipedia.org\/wiki\/Maunder_Minimum\">Maunder minimum<\/a>\u2019,\u201d said Zharkova. \u201cEffectively, when the waves are approximately in phase, they can show strong interaction, or resonance, and we have strong solar activity. When they are out of phase, we have solar minimums. When there is full phase separation, we have the conditions last seen during the Maunder minimum, 370 years ago.\u201d<\/em><\/p>\n<p>Dev&#8217;essere una semplificazione (non \u00e8 una critica, i modelli son fatti apposta e altri fanno previsioni analoghe, ma con ampi margini d&#8217;incertezza). Con due dinamo a moltiplicare le turbolenze, due onde &#8220;esattamente&#8221; simmetriche sarebbero sorprendenti, nelle <a href=\"https:\/\/upload.wikimedia.org\/wikipedia\/commons\/7\/73\/Carbon-14_with_activity_labels.png\" target=\"_blank\" rel=\"noopener\">ricostruzioni<\/a> non se ne vedono.<\/p>\n<p>Per quanto riguarda le condizioni terrestri, la <a href=\"http:\/\/cdn.arstechnica.net\/wp-content\/uploads\/2015\/06\/noaa_karl_etal-640x486.jpg\" target=\"_blank\" rel=\"noopener\">temperatura globale<\/a> aumenta nonostante l&#8217;attivit\u00e0 solare continui a calare, e aumenter\u00e0 anche se l&#8217;attivit\u00e0 della corona solare &#8211; non il Sole che continuer\u00e0 a brillare &#8211; si riducesse del 60%. Basta fare il conto: 400 ppm di CO2 atmosferica sono 2 watt\/mq e un ciclo solare 0,18 watt\/mq (arrotondo). La temperatura globale diminuirebbe di<a href=\"http:\/\/onlinelibrary.wiley.com\/doi\/10.1029\/2011JD017013\/full\" target=\"_blank\" rel=\"noopener\"><strong> 0,06-0,1 \u00b0C<\/strong><\/a>.<\/p>\n<p>Il paper di Sarah Ineson et al. uscito a fine giugno su <a href=\"http:\/\/www.nature.com\/ncomms\/2015\/150623\/ncomms8535\/full\/ncomms8535.html\" target=\"_blank\" rel=\"noopener\"><em>Nature Communications<\/em><\/a>, \u00e8 in open access, e nella bibliografia ci sono le ricerche astronomiche, paleoclimatiche in materia.<\/p>\n<p>Ineson et al. hanno usato un&#8217;insieme di\u00a0<a href=\"http:\/\/cmip-pcmdi.llnl.gov\/cmip5\/availability.html\" target=\"_blank\" rel=\"noopener\">modelli climatici<\/a> per prevedere gli effetti di un minimo come quello di Maunder, concentrandosi sugli inverni nell&#8217;emisfero nord, pi\u00f9 nevosi e piovosi in Europa soprattutto:<\/p>\n<p><em>The CMIP5 multi-model ensemble projects drying for the Mediterranean region, so in this sensitive region, wintertime alleviation is likely to be important. However, we note that the changes in this region are small and the confidence is relatively low.\u00a0<\/em><\/p>\n<p><img decoding=\"async\" class=\"aligncenter\" src=\"http:\/\/3.bp.blogspot.com\/-xleS-u4s_zk\/TalgthATbdI\/AAAAAAAAAhg\/yDwEgHCpNTk\/s1600\/orlando-tilda-swinton.jpg\" alt=\"\" \/><br \/>\nC&#8217;\u00e8 anche un&#8217;avvertenza per chi ha letto\/visto\u00a0<a href=\"https:\/\/it.wikipedia.org\/wiki\/Orlando_(romanzo)\" target=\"_blank\" rel=\"noopener\"><em>Orlando<\/em><\/a> e ricorda il ballo con Sasha sul Tamigi ghiacciato:<\/p>\n<p><em>We note that low solar activity does not guarantee cold conditions in any specific European winter as additional variability is introduced by other factors. The 360-year Central England Temperature record for December\u2013February shows that the coldest winters in the UK occurred at low solar activity, but, for example, 1685\/6, near the centre of the Maunder minimum, was the 5th warmest winter in the entire record.\u00a0This highlights the fact that solar variability acts only to bias the intrinsic year-to-year variability, which remains substantial for this region.<\/em><\/p>\n<p style=\"text-align: center;\">*<\/p>\n<p><strong>Agg. 13\/7<\/strong><br \/>\nrobertoin segnala <a href=\"http:\/\/www.radionz.co.nz\/national\/programmes\/morningreport\/audio\/201762133\/uk-scientist-suggests-a-mini-ice-age-be-upon-us\" target=\"_blank\" rel=\"noopener\">un&#8217;intervista<\/a> discutibile di V. Zharkova. Nel frattempo sono usciti articoli altrettanto discutibili sull&#8217;<a href=\"http:\/\/www.huffingtonpost.it\/2015\/07\/13\/sole-era-glaciale_n_7782912.html?ncid=fcbklnkithpmg00000001\" target=\"_blank\" rel=\"noopener\">Huffington Post<\/a>\u00a0e su <a href=\"http:\/\/www.ecoblog.it\/post\/158773\/altro-che-riscaldamento-globale-nel-2030-arriva-la-mini-glaciazione\" target=\"_blank\" rel=\"noopener\">Ecoblog<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Oltre alle previsioni dei globalcoolisti sull&#8217;era glaciale iniziata nel 1999 e rimandata di anno in anno, si susseguono quelle di scienziati d.o.c. su un minimo di attivit\u00e0 solare pari a quello di Maunder dal 1645 al 1715 circa, durante il quale ci sono stati inverni gelidi in Europa e nel Nord-America. I globalcoolisti\u00a0ci sperano, perch\u00e9&hellip; <a class=\"more-link\" href=\"https:\/\/archivio.ocasapiens.org\/index.php\/2015\/07\/12\/mini-era-glaciale\/\">Continua a leggere <span class=\"screen-reader-text\">Mini-era glaciale?<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5,10],"tags":[1482,2730,3625,4528,4563],"class_list":["post-28110","post","type-post","status-publish","format-standard","hentry","category-astronomia","category-clima","tag-co2","tag-forzante-solare","tag-irradianza","tag-minimo-di-maunder","tag-modelli","entry"],"_links":{"self":[{"href":"https:\/\/archivio.ocasapiens.org\/index.php\/wp-json\/wp\/v2\/posts\/28110","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/archivio.ocasapiens.org\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/archivio.ocasapiens.org\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/archivio.ocasapiens.org\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/archivio.ocasapiens.org\/index.php\/wp-json\/wp\/v2\/comments?post=28110"}],"version-history":[{"count":2,"href":"https:\/\/archivio.ocasapiens.org\/index.php\/wp-json\/wp\/v2\/posts\/28110\/revisions"}],"predecessor-version":[{"id":43187,"href":"https:\/\/archivio.ocasapiens.org\/index.php\/wp-json\/wp\/v2\/posts\/28110\/revisions\/43187"}],"wp:attachment":[{"href":"https:\/\/archivio.ocasapiens.org\/index.php\/wp-json\/wp\/v2\/media?parent=28110"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/archivio.ocasapiens.org\/index.php\/wp-json\/wp\/v2\/categories?post=28110"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/archivio.ocasapiens.org\/index.php\/wp-json\/wp\/v2\/tags?post=28110"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}