{"id":29025,"date":"2015-12-10T15:06:03","date_gmt":"2015-12-10T14:06:03","guid":{"rendered":"https:\/\/ocasapiens-dweb.blogautore.repubblica.it\/?p=29025"},"modified":"2021-12-05T20:14:56","modified_gmt":"2021-12-05T19:14:56","slug":"sorprese-alla-cop-21","status":"publish","type":"post","link":"https:\/\/archivio.ocasapiens.org\/index.php\/2015\/12\/10\/sorprese-alla-cop-21\/","title":{"rendered":"Sorprese alla COP 21"},"content":{"rendered":"

In un’intervista alla BBC, \u00a0il cardinale Turkson<\/a>\u00a0dice che per la Chiesa il controllo delle nascite \u00e8 una delle soluzioni ai problemi causati dai cambiamenti climatici, a condizione che venga usato un metodo naturale<\/em> – quale, a parte l’astinenza? – \u00a0la pillola \u00e8 esclusa. E \u00a0un fito-anticoncezionale?<\/p>\n

Gli Stati Uniti, dice John Kerry<\/a><\/strong>, si uniscono al gruppo che cerca un accordo per (tentare di) non superare un riscaldamento globale di 1,5 \u00b0C, rispetto al primo Ottocento – sembra un po’ irrealistico, vista la quantit\u00e0 di CO2 gi\u00e0 accumulata in atmosfera e limiti alle emissioni promessi che per ora promettono +2,7 \u00b0C.<\/p>\n

E’ uscito l’Expert Consensus on the Economics of Climate Change<\/strong><\/a>, un sondaggio di > mille economisti che avevano pubblicato paper in tema dal 1994 in poi. Il 93% dice che bisogna intervenire subito, l’1% che non \u00e8 un problema grave; il 5% che conviene aspettare ulteriori ricerche; l’1% non risponde. In breve:<\/p>\n

Economic experts believe that climate change will begin to have a net negative impact on the global economy very soon \u2013 the median estimate was \u201cby 2025,\u201d with 41% saying that climate change is already negatively affecting the economy… <\/em><\/p>\n

Lo ha fatto l’Institute for Policy Integrity di New York, quindi molte domande riguardano le proiezioni per \u00a0l’economia statunitense.<\/p>\n

*<\/p>\n

Da Climalteranti<\/a>,\u00a0<\/strong>Stefano Caserini riassume le trattative della \u00a0COP 21 e linka alla bozza odierna del “Paris agreement”, snellito da 51 a 27 pagine mentre le parentesi – termini ancora contestati – sono passate in 10 giorni \u00a0da 1.609 a 48<\/a><\/strong>.<\/p>\n

Allez, encore un p’tit effort…<\/p>\n

Anche\u00a0Chris Cesare<\/a><\/strong>, su Nature<\/em>, riassume le trattative, e segnala una brutta sorpresa in agguato: le simulazioni sull’andamento del permafrost in base agli impegni attuali, presentate ieri in una conferenza stampa<\/a>.<\/strong><\/p>\n

Susan Natali and her Woods Hole colleague and fellow permafrost expert Max Holmes explained that even for lower warming scenarios like this <\/em>(+ 2,7\u00b0 C, ndr), permafrost could emit 50 gigatons of carbon (or about 180 gigatons of carbon dioxide) in this century. This is because under lower warming scenarios, only about 30 percent, rather than about 70 percent, of surface layer permafrost is expected to thaw. <\/em><\/p>\n

Cos\u00ec si supera di un bel po’ il “budget del carbonio”. \u00a0Lo Hadley Centre<\/a><\/strong> era arrivato a una conclusione pi\u00f9 pessimista perch\u00e9 include anche le retroazioni delle “zone umide”:<\/p>\n

The feedbacks from wetlands and permafrost regions can be combined with other known processes to determine their greenhouse gas input into the atmosphere. For a global average temperature rise of 2 \u00b0C, this reduces the cumulative emissions that can be released by human actions by around 100GtC (360 GtCO2 ) in the most pessimistic simulation. This corresponds to about 10 years of anthropogenic emissions at the current rate. <\/em><\/p>\n

fonte<\/a><\/p>\n

Anthony De Angelis et al.<\/a> hanno trovato un difettone nelle simulazioni del ciclo idrologico. Si intensificherebbe meno del previsto regime di riscaldamento globale:<\/p>\n

Using an ensemble of climate models, here we show that such models tend to underestimate the sensitivity of solar absorption to variations in atmospheric water vapour, leading to an underestimation in the shortwave absorption increase and an overestimation in the precipitation increase. This sensitivity also varies considerably among models due to differences in radiative transfer parameterizations, explaining a substantial portion of model spread in the precipitation response. Consequently, attaining accurate shortwave absorption responses through improvements to the radiative transfer schemes could reduce the spread in the predicted global precipitation increase per degree warming for the end of the twenty-first century by about 35 per cent, and reduce the estimated ensemble-mean increase in this quantity by almost 40 per cent.<\/em><\/p>\n

Il difetto stava soprattutto nei vecchi modelli, scrive Steven Sherwood<\/a>,<\/strong> ma complimenti lo stesso:<\/p>\n

Their result is impressive, but its value for our understanding of climate change is more theoretical than practical. The main impacts from global warming will depend on regional changes in the amount and intermittency of precipitation, rather than on the global, time-averaged amount. Nonetheless, the finding is a wake-up call that radiative transfers of energy are a problem that is not completely solved, and that the partitioning of radiation flows in the atmosphere is as important for precipitation as the total heating of the Earth system is for its temperature.<\/em><\/p>\n

*<\/p>\n

Riservato ai soci \u00a0del fan club<\/strong>
\nDa collezione, la copertina di Nature<\/em>\u00a0dedicata alla nostra moscerina, a un pelo della sua schiena che le fa da organo del tatto, per la precisione, e alla ricerca di Emanuel Derivery et al. <\/a><\/strong>Hanno scoperto il trucco della divisione cellulare asimmetrica: grazie a quali molecole gli endosomi<\/a> si orientano verso una parte del fuso e da una staminale nascono due cellule una diversa dall’altra. Commento ammirato di Cayetano Gonzales<\/a>.<\/p>\n

*<\/p>\n

A proposito di staminali, adulte queste, un editoriale<\/a><\/strong> critica la scelta del governo giapponese che fa pagare ai pazienti parte del costo degli esperimenti clinici ai quali partecipano, il resto \u00e8 rimborsato dalla mutua:<\/p>\n

Japan has turned the drug-discovery model on its head. Usually, the investment \u2014 and thus the risk \u2014 is borne by drug companies, because they stand to gain in the long run. Now the risk is being outsourced. By the time it is clear whether a treatment works or not, the companies will have already made revenue from it.<\/em><\/p>\n

L’optogenetica – la tecnica<\/a><\/strong> per manipolare neuroni con la luce, controllare un circuito cerebrale e modificare un comportamento – non \u00e8 cos\u00ec \u00a0precisa come viene raccontato, stando agli esperimenti di Timothy Otchy et al.<\/a>\u00a0<\/strong>Commenta\u00a0Sara Reardon<\/a><\/strong>:<\/p>\n

In work with rats and zebra finches, neuroscientist Bence \u00d6lveczky of Harvard University in Cambridge, Massachusetts, and his team found that stimulating one part of the brain to induce certain behaviours might cause other, unrelated parts to fire simultaneously, and so make it seem as if these circuits are also involved in the behaviour.<\/em><\/p>\n

Oh bella. S’\u00e8 impennato il prezzo dell’agar, la gelatina di Gelinium<\/em> che da un secolo e mezzo si usa per le colture cellulari in tutti i lab del mondo, scrive Ewen Callaway<\/a><\/strong>. Il Marocco dove l’alga viene raccolta ha limitato le esportazioni:<\/p>\n

The shortage can be traced to newly enforced trade restrictions on the seaweed, arising from environmental concerns that the algae are being overharvested. It is unclear how deeply the dearth will hit researchers, but it has already pushed wholesale prices of agar to an all-time high of around US$35\u201345 per kilogram \u2014 nearly triple the price before scarcities began. Individual researchers, who buy packaged agar from lab-supply companies, can pay many times this amount.<\/em><\/p>\n

Davide Castelvecchi<\/a><\/strong> spiega (chapeau!) l’importanza del paper di Toby Cubitt et al. <\/a><\/strong>(versione<\/a><\/strong> lunga 142 pagine, gratis) sui problemi creati dai\u00a0teoremi d’incompletezza<\/a> di G\u00f6del, rivisti da Alan Turing, per la fisica quantistica. Rendono indecidibile, scrivono,<\/p>\n

The spectral gap\u2014the energy difference between the ground state and first excited state of a system … Our result implies that there exists no algorithm to determine whether an arbitrary model is gapped or gapless, and that there exist models for which the presence or absence of a spectral gap is independent of the axioms of mathematics.<\/em><\/p>\n

OMG!<\/p>\n","protected":false},"excerpt":{"rendered":"

In un’intervista alla BBC, \u00a0il cardinale Turkson\u00a0dice che per la Chiesa il controllo delle nascite \u00e8 una delle soluzioni ai problemi causati dai cambiamenti climatici, a condizione che venga usato un metodo naturale – quale, a parte l’astinenza? – \u00a0la pillola \u00e8 esclusa. E \u00a0un fito-anticoncezionale? Gli Stati Uniti, dice John Kerry, si uniscono al… Continua a leggere Sorprese alla COP 21<\/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":[2,10,13,16,22],"tags":[1608,3852,4563,4725,5280],"class_list":["post-29025","post","type-post","status-publish","format-standard","hentry","category-altri-animali","category-clima","category-drosophila-fanzine","category-fisica","category-neuroscienze","tag-cop-21","tag-kurt-godel","tag-modelli","tag-nature","tag-permafrost","entry"],"_links":{"self":[{"href":"https:\/\/archivio.ocasapiens.org\/index.php\/wp-json\/wp\/v2\/posts\/29025","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=29025"}],"version-history":[{"count":2,"href":"https:\/\/archivio.ocasapiens.org\/index.php\/wp-json\/wp\/v2\/posts\/29025\/revisions"}],"predecessor-version":[{"id":43860,"href":"https:\/\/archivio.ocasapiens.org\/index.php\/wp-json\/wp\/v2\/posts\/29025\/revisions\/43860"}],"wp:attachment":[{"href":"https:\/\/archivio.ocasapiens.org\/index.php\/wp-json\/wp\/v2\/media?parent=29025"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/archivio.ocasapiens.org\/index.php\/wp-json\/wp\/v2\/categories?post=29025"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/archivio.ocasapiens.org\/index.php\/wp-json\/wp\/v2\/tags?post=29025"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}