Grein í Nature: Kenning Henriks Svensmark um áhrif geimgeisla og sólvirkni á skýjafar virðist hafa verið staðfest hjá CERN...

 

 

 

Í hinu þekkta ritrýnda vísindariti Nature birtist í dag grein um niðurstöður tilraunarinnar CLOUD hjá CERN í Sviss. Niðurstöðurnar eru mjög jákvæðar fyrir kenninguna um samspil geimgeisla, virkni sólar og skýjafars. 

Til hamingju Henrik Svensmark!

Sjá frétt sem birtist á vefsíðu Nature í dag: http://www.nature.com/news/2011/110824/full/news.2011.504.html

Cloud formation may be linked to cosmic rays

Experiment probes connection between climate change and radiation bombarding the atmosphere.

It sounds like a conspiracy theory: 'cosmic rays' from deep space might be creating clouds in Earth's atmosphere and changing the climate. Yet an experiment at CERN, Europe's high-energy physics laboratory near Geneva, Switzerland, is finding tentative evidence for just that.

The findings, published today in Nature¹, are preliminary, but they are stoking a long-running argument over the role of radiation from distant stars in altering the climate....

Meira hér.

---

Úrdrátt úr greininni má lesa hér á vefsíðu Nature: http://www.nature.com/nature/journal/v476/n7361/full/nature10343.html

Role of sulphuric acid, ammonia and galactic cosmic rays in atmospheric aerosol nucleation

 ...

Atmospheric aerosols exert an important influence on climate¹ through their effects on stratiform cloud albedo and lifetime² and the invigoration of convective storms³. Model calculations suggest that almost half of the global cloud condensation nuclei in the atmospheric boundary layer may originate from the nucleation of aerosols from trace condensable vapours⁴, although the sensitivity of the number of cloud condensation nuclei to changes of nucleation rate may be small^{5, 6}. Despite extensive research, fundamental questions remain about the nucleation rate of sulphuric acid particles and the mechanisms responsible, including the roles of galactic cosmic rays and other chemical species such as ammonia⁷. Here we present the first results from the CLOUD experiment at CERN. We find that atmospherically relevant ammonia mixing ratios of 100 parts per trillion by volume, or less, increase the nucleation rate of sulphuric acid particles more than 100–1,000-fold. Time-resolved molecular measurements reveal that nucleation proceeds by a base-stabilization mechanism involving the stepwise accretion of ammonia molecules. Ions increase the nucleation rate by an additional factor of between two and more than ten at ground-level galactic-cosmic-ray intensities, provided that the nucleation rate lies below the limiting ion-pair production rate. We find that ion-induced binary nucleation of H2SO4–H2O can occur in the mid-troposphere but is negligible in the boundary layer. However, even with the large enhancements in rate due to ammonia and ions, atmospheric concentrations of ammonia and sulphuric acid are insufficient to account for observed boundary-layer nucleation.

Meira hér.

Hér er um að ræða áfangaskýrslu, og tilraunum ekki lokið. Það er þó vissulega ánægjulegt þegar menn sjá árangur erfiðis síns. Það er þó rétt og skylt að draga ekki neinar ályktanir strax, því fæst orð hafa minnsta ábyrgð...   Það er þó óhætt að segja að þetta sé verulega áhugavert og spennandi...

Var einhver að hvísla, ætli Henrik Svensmark eigi eftir að fá Nóbelsverðlaunin í eðlisfræði? Hver veit?  :-)

                                                                  *****

 

 

                                                                   *****

 

Eldri pistlar um kenningu Henriks Svensmark:

Er jörðin að hitna? Ekki er allt sem sýnist... 1. febrúar 1998.

Merkileg tilraun: Geimgeislar, ský og loftslagsbreytingar... 1. janúar 2007.

Byltingarkennd kenning dansks vísindamanns skekur vísindaheiminn....20. feb. 2007.

Nýjar fréttir af Svensmark tilrauninni hjá CERN í Sviss... 8. júní 2009

Ný grein Henriks Svensmark um loftslagsbreytingar af völdum sólar og geimgeisla birt í Geophysical Research Letters í dag 1. ágúst... 1. ágúst 2009.

Prófessor Henrik Svensmark: »Vi anbefalervores venner at nyde den globale opvarmning, mens den varer«...  11. september 2009.

Ný tilraun við Árósarháskóla rennir stoðum undir kennirnar Henriks Svensmarks um áhrif geimgeisla og sólar á skýjafar - og þar með væntanlega á hnatthlýnun eða hnattkólnun...  5. júní 2011.

Nokkrar krækjur:

 Cosmic rays get ahead in CLOUD
http://www.rsc.org/chemistryworld/News/2011/August/24081102.asp

Cloud formation may be linked to cosmic rays
http://www.nature.com/news/2011/110824/full/news.2011.504.html

Svensmarks klimateori får rygstød fra Cern
http://ing.dk/artikel/121410-svensmarks-klimateori-faar-rygstoed-fra-cern

Probing the cosmic-ray–climate link
http://physicsworld.com/cws/article/news/46953

Klimaforschung am Teilchenbeschleuniger: Beschreibung der Aerosolneubildung muss revidiert werden
http://www.psi.ch/media/klimaforschung-am-teilchenbeschleuniger-in-german

CERN experiment confirms cosmic ray action
http://calderup.wordpress.com

 

                                                      --- --- ---

 

 Uppfært 30.8.2011: 

Þegar greinin sjálf er lesin kemur í ljós að hún er alls ekki ný. Hún er send Nature 9. september 2010, og væntanlega skrifuð nokkru áður, eða fyrir meira en ári.
"Received 9 September 2010; accepted 24 June 2011".

CLOUD tilrauninni hjá CERN er þó alls ekki lokið ennþá.

 

Uppfært 1.9.2011:

Prófessor dr. Nir Shaviv skrifar í dag grein hér sem vert er að lesa. Hann er einstaklega vel að sér í loftslagsfræðum, og því vert að veita athygli hvaða skoðun hann hefur.

Greinin byrjar þannig: "The CLOUD collaboration from CERN finally had their results published in Nature (TRF, full PDF), showing that ionization increases the nucleation rate of condensation nuclei. The results are very beautiful and they demonstrate, yet again, how cosmic rays (which govern the amount of atmospheric ionization) can in principle have an effect on climate.

What do I mean? First, it is well known that solar variability has a large effect on climate. In fact, the effect can be quantified and shown to be 6 to 7 times larger than one could naively expect from just changes in the total solar irradiance. This was shown by using the oceans as a huge calorimeter (e.g., as described here). Namely, an amplification mechanism must be operating.

One mechanism which was suggested, and which now has ample evidence supporting it, is that of solar modulation of the cosmic ray flux (CRF), known to govern the amount of atmospheric ionization. This in turn modifies the formation of cloud condensation nuclei, thereby changing the cloud characteristics (e.g. their reflectivity and lifetime). For a few year old summary, take a look here.

So, how do we know that this mechanism is necessarily working? ...".    [MEIRA]

 Áhugavert myndband með Nir Shaviv er hér. Myndbandið er frá árinu 2010.

 

 

 

 (Er ekki annars merkilegt hve sumir (margir?) hafa miklar áhyggjur af því að
kenningar Svensmarks reynist réttar...   
Auðvitað ættu allir að gleðjast ef svo reynist, því þá væri ljóst að
hlýnun undanfarinna áratuga sé að miklu (mestu?) leyti að völdum náttúrulegra breytinga,
og á því væntanlega eftir að ganga til baka.
Þá geta menn farið að anda rólega aftur, eða anda með nefinu eins og sagt er...).