Negli ultimi mesi si sono moltiplicati i segnali preoccupanti sullo stato del clima sulla Terra. Un quadro per molti versi critico e distribuito su più fronti, dal riscaldamento globale ai cambiamenti climatici fino ai disastri naturali. Fenomeni molto complessi e tra loro correlati che sempre più spesso hanno un pesante impatto negativo sull’ambiente e su milioni di persone. Gli ultimi dati presentati poche ore fa dall’Organizzazione Meteorologica Mondiale (World Meteorological Organization – WMO) aggiungono un ulteriore tassello a questo quadro puntando l’obiettivo su uno dei parametri più significativi a livello globale, vale a dire la concentrazione di CO2 (anidride carbonica) in atmosfera.
Un anno di dati preoccupanti
L’ultimo biennio sembra ormai destinato a passare agli archivi per una lunga sequenza di dati preoccupanti su clima ed ambiente. Che la situazione avesse raggiunto un elevato grado di criticità si era intuito giù durante i lavori della COP21 alla fine del 2015. Ma da li in avanti le cifre allarmanti si sono costantemente ripresentate. I dati GISS/NASA, ad esempio, hanno più volte evidenziato come nel corso del 2016 si siano registrati ripetuti picchi storici nelle temperature medie. Nella scorsa estate un rapporto di Greenpeace ha anche evidenziato come gli effetti del riscaldamento globale siano stati particolarmente severi sull’Artico. Il recentissimo accordo di Kigali ha ribadito i rischi dell’effetto serra ed ha messo in campo nuove azioni di contenimento.
In questo scenario i dati pubblicati nel WMO Greenhouse Gas Bulletin aggiungono una ulteriore chiave di lettura ai fenomeni in corso. L’Organizzazione Meteorologica Mondiale ha infatti stabilito che nel 2015 la concentrazione di CO2 in atmosfera ha raggiunto nuovi livelli record superando la soglia delle 400 parti per milione (ppm). In passato sforamenti di questo valore simbolico si erano avuti in alcuni periodi dell’anno o in alcune zone limitate. Ora però la barriera delle 400 ppm è stata stabilmente superata a livello globale ed i dati acquisiti per il 2016 suggeriscono che anche nell’anno in corso non si registrerà alcuna inversione di tendenza.
El Niño e la CO2 in atmosfera
Tra le case che negli ultimi due anni hanno portato ad un incremento della CO2 in atmosfera, il WMO individua anche El Niño. Questo fenomeno climatico si manifesta con particolare intensità da ormai molti mesi ed ha come conseguenza diretta estesi fenomeni di siccità nella zone tropicali. In una sorta di effetto domino la riduzione delle foreste nella fascia tra i due tropici ha ridotto le capacità di riassorbimento della CO2 aumentando la parte che resta in atmosfera. La stessa siccità innescata da El Niño ha anche aumentato diffusione e dimensione degli incendi a loro volta fonte di CO2.
Se El Niño è tra i responsabili dei picchi di concentrazione di anidride carbonica, è comunque evidente che la tendenza di fondo resta quella di un costante incremento. Negli anni ’80 ad esempio la concentrazione di CO2 in atmosfera era ancora al di sotto delle 350 ppm.
Lo stato della CO2
Secondo i dati del bollettino WMO l’anidride carbonica (CO2) rappresenta il 65 del forzante radioattivo dei gas serra di lungo periodo. Si tratta quindi della componente più rilevante nel meccanismo dell’effetto serra che intrappola nell’atmosfera una maggiore quantità di energia (e quindi di calore). In questo senso la dinamica della concentrazione di CO2 è particolarmente significativa e direttamente collegata con l’attività dell’uomo. Nell’era pre-industriale si registravano infatti 278 ppm in una condizione di sostanziale equilibrio degli scambi tra atmosfera, oceani e biosfera.
Nel 2015 la concentrazione media annua ha come detto raggiunto le 400 ppm con un incremento del 144% rispetto ai livelli pre-industriali. Questa condizione evidenzia un sistema non più in equilibrio in cui le nuove emissioni di CO2 non riescono più ad essere bilanciate.
Metano e protossido di azoto
Il metano è il secondo gas serra in atmosfera responsabile del 17% del forzante radioattivo. Mentre il 40% del metano in atmosfera è di origine naturale, il restante 60% dipende dall’azione umana ed in particolare dall’allevamento di bestiame, dall’agricoltura e dall’uso di combustibili fossili. Nel 2015 la concentrazione di metano in atmosfera ha raggiunto le 1845 parti per miliardo (ppb) con un incremento del 256% rispetto all’era pre-industriale.
Una dinamica simile è seguita anche dal protossido di azoto (N2O), gas che ha un ruolo importante nel fenomeno della riduzione dello strato di ozono. La sua presenza in atmosfera è dovuta al 40% all’azione antropica. La concentrazione di protossido di azoto ha raggiunto le 328 ppb con un incremento del 121% rispetto all’era pre-industriale.
Tra gli altri gas serra si registra la progressiva riduzione dei clorofluorocarburi. Queste sostanze sono state messe progressivamente al bando con il Protocollo di Montréal in quanto considerate responsabili del così detto buco dell’ozono. Al contrario è in crescita la concentrazione di idrofluorocarburi, potenti gas serra al centro del recente accordo di Kigali.
Dati per la COP22
Nel presentare il nuovo bollettino sui gas serra, il WMO sottolinea l’importanza dell’accordo di Kigali che in estensione del Protocollo di Montréal prevede la progressiva eliminazione degli idrofluorocarburi con l’obiettivo di ridurre l’effetto serra. Il WMO però evidenzia anche come il problema fondamentale resti legato alla CO2 che come detto è il gas maggiore responsabile dell’effetto serra.
Le cifre fornite dal WMO saranno al centro dei dibattiti e delle trattative anche alla prossima COP22 in programma a Marrakech dal 7 al 18 novembre 2016.
Photo | Thinkstock
I just want to mention I am new to weblog and truly loved your web blog. Probably I’m planning to bookmark your website . You definitely have remarkable posts. Bless you for revealing your blog site.
Very good written article. It will be helpful to everyone who employess it, as well as yours truly :). Keep doing what you are doing – looking forward to more posts.
Great write-up, I am regular visitor of one¡¦s site, maintain up the excellent operate, and It is going to be a regular visitor for a long time.
very nice blog!
http://wirosableng.edan
F*ckin’ awesome issues here. I am very glad to see your article. Thanks a lot and i’m looking ahead to contact you. Will you please drop me a mail?
It’s appropriate occasion to construct some preparations for the future. I have go through this blog posting and if I would, I want to recommend you number of entertaining suggestions.
http://www.shortmyurls.com/emeryeps
Definitely, what a great blog and revealing posts, I surely will bookmark your blog.Have an awsome day!
I do trust all the concepts you’ve presented for your post. They are very convincing and can definitely work. Nonetheless, the posts are very quick for beginners. May you please prolong them a bit from next time? Thanks for the post.
Divorcemind.com is a online divorce resource for divorce attorney, attornies and lawyers. You will find the best divorce information online. Divorce Mind will make your divorce or separation a quick, convenient and private.
http://www.shortmyurls.com/divorcemind-divorces-comment
You have remarked very interesting details! ps nice internet site.
I do not even know how I ended up here, but I thought this post was great. I do not know who you are but definitely you’re going to a famous blogger if you are not already
Cheers!
Divorcemind.com is a online divorce resource for divorce attorney, attornies and lawyers. You will find the best divorce information online. Divorce Mind will make your divorce or separation a quick, convenient and private.
http://www.shortmyurls.com/divorcemind-divorce-attorney-comment-gen
Between me and my husband we’ve owned more MP3 players over the years than I can count, including Sansas, iRivers, iPods (classic & touch), the Ibiza Rhapsody, etc. But, the last few years I’ve settled down to one line of players. Why? Because I was happy to discover how well-designed and fun to use the underappreciated (and widely mocked) Zunes are.
IMSC SEO is a Singapore SEO Company. They provide comprehensive Singapore SEO services to help SG businesses to gain traffic from search engine. Their SEO agency has many years of experiences working with overseas companies on more competitive grounds. They are the best seo company in Singapore you can find. Their SEO expert and consultant understand exactly what search engine optimization your company need to gain search engine traffic.
http://www.shortmyurls.com/imsc-home-comment-general
IMSC SEO is a Singapore SEO Company. They provide comprehensive Singapore SEO services to help SG businesses to gain traffic from search engine. Their SEO agency has many years of experiences working with overseas companies on more competitive grounds. They are the best seo company in Singapore you can find. Their SEO expert and consultant understand exactly what search engine optimization your company need to gain search engine traffic.
http://www.shortmyurls.com/imsc-services-comment-exact
I was extremely pleased to uncover this site. I wanted to thank you for your time just for this wonderful read!! I definitely liked every bit of it and I have you saved to fav to check out new stuff in your website.
http://www.thedepartmentofaesthetics.org
I simply wish to reveal to you that I am new to blog posting and really loved your website. Most likely I am probably to bookmark your blog post . You seriously have amazing article blog posts. Like it for share-out with us your web post
http://www.losangelesseo4.info
Fantastic beat ! I would like to apprentice while you amend your website, how could i subscribe for a blog site? The account helped me a acceptable deal. I had been tiny bit acquainted of this your broadcast offered bright clear concept
It’s nearly impossible to come across well-updated readers on this issue, even though you come across as like you be aware of exactly what you’re covering! Bless You
http://www.meditation2.info
You made some decent points there. I did a search on the subject matter and found most persons will agree with your site.
It happens to be proper time to put together some goals for the extended term. I’ve go through this blog and if I could, I wish to recommend you a few great tips.
http://newbetaworksserver.com
I merely wish to inform you that I am new to having a blog and extremely valued your report. Very likely I am likely to remember your blog post . You seriously have excellent article materials. Get Pleasure From it for share-out with us your favorite domain page
http://www.searchengineoptimization1.info
Hi there, just got aware of your blog page through The Big G, and have found that it’s seriously helpful. I will take pleasure in if you decide to keep up this post.
http://www.cnelectrictools.com
I’m extremely pleased to find this site. I wanted to thank you for your time for this particularly wonderful read!! I definitely really liked every bit of it and i also have you book marked to look at new information in your site.
http://www.jcccafe.com
Excellent read, I just passed this onto a friend who was doing some research on that. And he actually bought me lunch as I found it for him smile So let me rephrase that: Thank you for lunch!
Fairly informative highlights that you have mentioned, warm regards for writing.
http://www.membershipcareers.com
The Zune concentrates on being a Portable Media Player. Not a web browser. Not a game machine. Maybe in the future it’ll do even better in those areas, but for now it’s a fantastic way to organize and listen to your music and videos, and is without peer in that regard. The iPod’s strengths are its web browsing and apps. If those sound more compelling, perhaps it is your best choice.
Wonderful site. A lot of helpful information here. I¡¦m sending it to a few friends ans also sharing in delicious. And of course, thanks to your effort!
Exceedingly entertaining points that you have remarked, thank you for setting up.
http://www.volunteerworkafrica.com
Seriously significant elements you’ll have remarked, thanks a lot for setting up.
http://www.companionprogram.net
It really is mostly unthinkable to encounter well-updated parties on this niche, then again you seem like you be aware of the things that you’re raving about! Appreciate It
http://www.eggvoting.us
Thanks so much for providing individuals with an extremely splendid possiblity to read critical reviews from this web site. It is always very superb plus full of amusement for me and my office peers to visit your site at the least 3 times in 7 days to read the fresh things you have. And of course, I am always motivated with the mind-boggling hints you serve. Selected 2 points on this page are in truth the most efficient I have ever had.
whoah this weblog is magnificent i like studying your articles. Keep up the great paintings! You recognize, a lot of people are hunting round for this information, you can aid them greatly.
I like the valuable information you provide in your articles. I’ll bookmark your blog and check again here frequently. I am quite sure I’ll learn a lot of new stuff right here! Best of luck for the next!
I’m not sure where you’re getting your information, but great topic. I needs to spend some time learning much more or understanding more. Thanks for magnificent info I was looking for this information for my mission.
As I site possessor I believe the content matter here is rattling wonderful , appreciate it for your efforts. You should keep it up forever! Good Luck.
I like the valuable info you provide in your articles. I will bookmark your weblog and check again here frequently. I’m quite sure I will learn many new stuff right here! Good luck for the next!
I like what you guys are up also. Such intelligent work and reporting! Keep up the excellent works guys I have incorporated you guys to my blogroll. I think it will improve the value of my web site
I simply need to share it with you that I am new to writing a blog and undeniably loved your review. Probably I am most likely to save your blog post . You indeed have impressive article blog posts. Truly Appreciate it for swapping with us all of your site webpage
http://www.denverseo3.info
I was pretty pleased to find this great site. I need to to thank you for ones time just for this wonderful read!! I definitely liked every little bit of it and i also have you book-marked to check out new stuff in your blog.
http://www.biciraq.org
I have recently started a web site, the info you provide on this website has helped me greatly. Thank you for all of your time & work.
Noticeably intriguing suggestions that you have mentioned, many thanks for putting up.
http://www.monclermoinscherboutique.com
Good day there, just became receptive to your post through yahoo, and found that it’s genuinely informational. I’ll truly appreciate should you decide continue on this post.
http://www.stdtestinginfo.net
I loved as much as you will receive carried out right here. The sketch is attractive, your authored subject matter stylish. nonetheless, you command get got an impatience over that you wish be delivering the following. unwell unquestionably come more formerly again as exactly the same nearly a lot often inside case you shield this increase.
My spouse and i felt absolutely joyous when John could carry out his investigations while using the ideas he had using your blog. It is now and again perplexing just to choose to be giving for free tips and hints other people could have been trying to sell. We fully understand we’ve got the website owner to thank for that. The specific explanations you made, the simple site navigation, the relationships you can help to engender – it’s most fantastic, and it’s really making our son and us reckon that that issue is fun, which is pretty pressing. Thanks for the whole lot!
Thanks for another great article. The place else may just anyone get that type of information in such an ideal manner of writing? I have a presentation subsequent week, and I am at the look for such info.
I will immediately grab your rss as I can’t in finding your e-mail subscription hyperlink or newsletter service. Do you’ve any? Kindly allow me recognise in order that I may just subscribe. Thanks.
It really is the right occasion to get some schedules for the forthcoming future. I have study this article and if I could, I want to suggest you few worthwhile recommendations.
http://www.friendsoftheutgardens.org